Form 8-K

8-K — OMNICOM GROUP INC.

Accession: 0000029989-26-000008

Filed: 2026-04-28

Period: 2026-04-28

CIK: 0000029989

SIC: 7311 (SERVICES-ADVERTISING AGENCIES)

Item: Results of Operations and Financial Condition

Item: Regulation FD Disclosure

Item: Financial Statements and Exhibits

Documents

8-K — omc-20260428.htm (Primary)

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8-K

8-K (Primary)

Filename: omc-20260428.htm · Sequence: 1

omc-20260428

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UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, DC 20549

FORM 8-K

CURRENT REPORT

PURSUANT TO SECTION 13 OR 15(d) OF THE

SECURITIES EXCHANGE ACT OF 1934

Date of Report (Date of earliest event reported): April 28, 2026

OMNICOM GROUP INC.

(Exact Name of Registrant as Specified in its Charter)

New York

1-10551

13-1514814

(State or other jurisdiction

of incorporation)

(Commission

File Number)

(IRS Employer

Identification No.)

280 Park Avenue, New York, NY

10017

(Address of principal executive offices) (Zip Code)

Registrant’s telephone number, including area code: (212) 415-3600

Not Applicable

(Former name or former address, if changed since last report)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

☐ Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

☐ Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

☐ Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

☐ Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Securities registered pursuant to Section 12(b) of the Act:

Title of each class Trading Symbol Name of each exchange on which registered

Common Stock, par value $0.15 per share OMC New York Stock Exchange

0.800% Senior Notes due 2027 OMC/27 New York Stock Exchange

1.400% Senior Notes due 2031 OMC/31 New York Stock Exchange

3.700% Senior Notes due 2032 OMC/32 New York Stock Exchange

2.250% Senior Notes due 2033 OMC/33 New York Stock Exchange

3.850% Senior Notes due 2034 OMC/34 New York Stock Exchange

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter).

Emerging growth company ☐

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐

Item 2.02. Results of Operations and Financial Condition.

On April 28, 2026, Omnicom Group Inc. ("Omnicom," the "Company," "we," "our" or "us") published an earnings release reporting its financial results for the three months ended March 31, 2026. A copy of the earnings release is furnished as Exhibit 99.1 to this report and is incorporated by reference herein in its entirety.

Item 7.01. Regulation FD Disclosure.

On April 28, 2026, Omnicom hosted an earnings call and posted on its website a related investor presentation in connection with publishing its financial results for the three months ended March 31, 2026. A copy of the presentation is furnished as Exhibit 99.2 to this report and is incorporated by reference herein in its entirety.

The information under Items 2.02 and 7.01 above (including Exhibits 99.1 and 99.2 hereto) is being furnished and shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended, or otherwise subject to the liabilities of that section, nor shall it be deemed incorporated by reference in any filing under the Securities Act of 1933, as amended, except as expressly set forth by specific reference in such filing.

Forward-Looking Statements.

Certain statements in the exhibits to this Current Report on Form 8-K contain forward-looking statements, including statements within the meaning of the Private Securities Litigation Reform Act of 1995, as amended. In addition, from time to time, we or our representatives have made, or may make, forward-looking statements, orally or in writing. These statements, other than statements of historical fact, may discuss goals, intentions and expectations as to future plans, trends, events, results of operations or financial condition, or otherwise, based on current beliefs of our management as well as assumptions made by, and information currently available to, our management. Forward-looking statements may be accompanied by words such as “aim,” “anticipate,” “believe,” “plan,” “could,” “should,” “would,” “estimate,” “expect,” “forecast,” “future,” “guidance,” “intend,” “may,” “will,” “possible,” “potential,” “predict,” “project” or similar words, phrases or expressions. These forward-looking statements are subject to various risks and uncertainties, many of which are outside our control. Therefore, you should not place undue reliance on such statements. Factors that could cause actual results to differ materially from those in the forward-looking statements include:

•risks relating to the completed merger (the “Merger”) between us and The Interpublic Group of Companies, Inc. ("IPG"), including risks related to the integration of IPG’s business, such as, among others: uncertainties associated with retaining key management and other employees; potential disruptions to client, vendor, and business partner relationships; the risk that integration activities may be more time-consuming, complex, or costly than expected; the possibility that anticipated synergies, efficiencies, and other benefits of the Merger may not be realized, or may be realized more slowly than anticipated; and risks associated with managing a larger, more complex combined organization and effectively integrating systems, processes, operations, and cultures;

•adverse economic conditions, including geopolitical events, international hostilities, acts of terrorism, public health crises, inflation or stagflation, tariffs and other trade barriers, central bank interest rate policies in countries that comprise our major markets, labor and supply chain issues affecting the distribution of our clients’ products, or a disruption in the credit markets;

•international, national or local economic conditions that could adversely affect the Company or our clients;

•reductions in client spending, a slowdown in client payments or a deterioration or disruption in the credit markets;

•the ability to attract new clients and retain existing clients in the manner anticipated;

•changes in client marketing and communications services requirements;

•failure to manage potential conflicts of interest between or among clients;

•unanticipated changes related to competitive factors in the marketing and communications services industries;

•unanticipated changes to, or an inability to hire and retain, key personnel;

•currency exchange rate fluctuations;

•reliance on information technology systems and risks related to cybersecurity incidents;

•effective management of the risks, challenges and efficiencies presented by utilizing artificial intelligence, or AI, technologies and related partnerships in our business, and their use by our competitors;

•failure to adapt to technological developments;

•our liquidity, long-term financing needs, credit ratings and access to capital markets;

•changes in legislation or governmental regulations affecting the Company or our clients;

•losses on media purchases and production costs incurred on behalf of clients;

•risks associated with assumptions the Company makes in connection with our acquisitions, critical accounting estimates and legal proceedings;

•the Company’s international operations, which are subject to the risks of currency repatriation restrictions, social or political conditions and an evolving regulatory environment in high-growth markets and developing countries;

•risks related to our environmental, social and governance goals and initiatives, including impacts from regulators and other stakeholders, and the impact of factors outside of our control on such goals and initiatives;

•changes in tax rates, tax laws, regulations or interpretations, or adverse outcomes of tax audits or proceedings; and

•other business, financial, operational and legal risks and uncertainties detailed from time to time in our filings with the Securities and Exchange Commission ("SEC").

The foregoing list of factors is not exhaustive. You should carefully consider the foregoing factors and the other risks and uncertainties that may affect the Company’s business, including those described in Item 1A, “Risk Factors” and Item 7, “Management’s Discussion and Analysis of Financial Condition and Results of Operations” in our Annual Report on Form 10-K and in other documents filed from time to time with the Securities and Exchange Commission. Except as required under applicable law, the Company does not assume any obligation to update these forward-looking statements.

Item 9.01. Financial Statements and Exhibits.

(d) Exhibits.

Exhibit Number Description

99.1

Earnings release dated April 28, 2026.

99.2

Investor presentation materials dated April 28, 2026.

104 The cover page from this Current Report on Form 8-K, formatted in Inline XBRL

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

Omnicom Group Inc.

By: /s/ Andrew L. Castellaneta

Name: Andrew L. Castellaneta

Title:

Senior Vice President,

Chief Accounting Officer

Date: April 28, 2026

EX-99.1

Filename: a2026q1earningsrelease.htm · Sequence: 2

Document

OMNICOM REPORTS FIRST QUARTER 2026 RESULTS

2026 First Quarter - Core Operations (Net of Dispositions and Held for Sale):

•Revenue of $5.6 billion, 3.9% organic growth

•Non-GAAP Adjusted EBITA of $833.5 million, 14.8% margin

2026 First Quarter:

•Revenue of $6.2 billion

•Diluted earnings per share of $1.35; $1.90 Non-GAAP Adjusted, up 12%

•Operating Income of $646.2 million; $861.4 million Non-GAAP Adjusted EBITA

NEW YORK, April 28, 2026 - Omnicom (NYSE: OMC) today announced results for the quarter ended March 31, 2026.

“Our strong first quarter performance as the new Omnicom reflects our new integrated capabilities, core portfolio operations, and successful integration activities. With the largest global media platform, proprietary data and identity capabilities, and our AI-powered Omni platform in full operation, we are uniquely equipped to help clients address an increasingly fragmented and complex marketing environment," said John Wren, Chairman and Chief Executive Officer of Omnicom. “In the quarter, we delivered solid revenue growth and double-digit growth in Non-GAAP adjusted diluted EPS. We are also on track to achieve substantial cost reduction synergies and $3.5 billion in share repurchases this year under our $5.0 billion authorization. This combination of operational excellence and disciplined capital allocation positions us to deliver profitability and earnings-per-share growth that will set a new standard for our sector.”

Core Operations

Three Months Ended March 31,

$ in millions, except per share amounts 2026 2025

Omnicom Combined (OMC + IPG)

2026 Consolidated

Less: Dispositions & Held for Sale Core Operations (Net of Dispositions & Held for Sale)

2025

Combined

Less: Dispositions & Held for Sale Core Operations (Net of Dispositions & Held for Sale)

Revenue $ 6,242.9 $ 627.2 $ 5,615.7 $ 6,013.0 $ 748.3 $ 5,264.7

Adjusted EBITA $ 861.4 $ 27.9 $ 833.5 $ 694.7 $ 41.6 $ 653.1

EBITA Margin 13.8 % 4.4 % 14.8 % 11.6 % 5.6 % 12.4 %

See notes on pages 2 and 13.

Revenue from Core Operations

Revenue from Core Operations in the first quarter of 2026 increased $350.9 million, or 6.7%, to $5.6 billion as compared to the first quarter of 2025 due to an increase in organic revenue of $206.7 million, or 3.9%, and an increase due to foreign currency translation of $144.2 million, or 2.7%.

280 Park Avenue, New York, NY 10017, www.omc.com

Revenue contribution by discipline as a percentage of revenue from Core Operations of $5.6 billion in the first quarter of 2026 was as follows: $2.9 billion, or 51.5%, for Integrated Media; $943.4 million, or 16.8%, for Advertising; $535.5 million, or 9.5%, for Health; $659.8 million, or 11.7%, for Public Relations; and $582.8 million, or 10.4%, for Experiential & Other. Revenue from dispositions and assets held for sale was $627.2 million.

Revenue contribution by region as a percentage of revenue from Core Operations of $5.6 billion in the first quarter of 2026 was as follows: $3.4 billion, or 61.4%, for the United States; $690.0 million, or 12.3%, for Euro Markets & Other Europe; $492.3 million, or 8.8%, for the United Kingdom; $503.5 million, or 8.9%, for Asia Pacific; $174.4 million, or 3.1%, for Latin America; $129.8 million, or 2.3%, for the Middle East & Africa; and $177.8 million, or 3.2%, for Other North America.

Adjusted EBITA from Core Operations

Adjusted EBITA from Core Operations in the first quarter of 2026 increased $178.5 million, or 27.3%, to $833.5 million in the first quarter of 2026 compared to the first quarter of 2025, and the related margin increased to 14.8% from 12.4%, primarily due to cost reduction synergies.

Core Operations

Core Operations: calculated from the consolidated revenue, adjusted operating income and adjusted EBITA of Omnicom, excluding businesses that have been disposed of or are classified as held for sale. Amounts for 2025 are calculated on a combined basis for Omnicom and The Interpublic Group of Companies, Inc. ("IPG").

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First Quarter 2026 Results

$ in millions, except per share amounts

Three Months Ended March 31,

Reported 2026 Non-GAAP Adjustments Non-GAAP 2026 Adj. Reported 2025 Non-GAAP Adjustments Non-GAAP 2025 Adj.

Revenue $ 6,242.9 $ — $ 6,242.9 $ 3,690.4 $ — $ 3,690.4

Operating Income

646.2 97.8 744.0 452.6 33.8 486.4

Operating Income Margin 10.4 % 11.9 % 12.3 % 13.2 %

Net Income1

405.2 164.5 569.7 287.7 48.8 336.5

Net Income per Share - Diluted1

$ 1.35 $ 1.90 $ 1.45 $ 1.70

Non-GAAP Measures:1

EBITA $ 763.6 $ 97.8 $ 861.4 $ 474.4 $ 33.8 $ 508.2

EBITA Margin 12.2 % 13.8 % 12.9 % 13.8 %

1) See notes on page 13.

Revenue

Revenue in the first quarter of 2026 increased $2.6 billion to $6.2 billion as compared to the first quarter of 2025, primarily due to the acquisition of IPG, which closed on November 26, 2025, and constant currency revenue growth. The impact of foreign currency translation increased revenue by $174.2 million, or 4.8%. Revenue in the first quarter of 2026 includes $627.2 million from dispositions and assets held for sale.

Expenses

Operating expenses increased $2.4 billion to $5.6 billion in the first quarter of 2026 compared to the first quarter of 2025, primarily due to the acquisition of IPG. Included in operating expenses in the first quarter of 2026 are $59.4 million of integration and transaction costs related to the acquisition of IPG, $4.1 million of repositioning costs, and $34.3 million of loss on planned dispositions following the closing of the IPG acquisition.

Salary and service costs increased $1.9 billion to $4.6 billion, primarily due to the IPG acquisition and constant currency revenue growth. These costs tend to fluctuate with changes in revenue and are comprised of salary and related costs, which include employee compensation and benefits costs and freelance labor, third-party service costs, and third-party incidental costs. Salary and related costs increased $1.3 billion to $3.1 billion. Third-party service costs increased $568.9 million to $1.4 billion, primarily due to growth in our Integrated Media discipline and the effects of including a full quarter of IPG costs. Third-party incidental costs increased $43.3 million to $212.3 million, primarily due to revenue growth and the acquisition of IPG.

Occupancy and other costs, which are less directly linked to changes in revenue than salary and service costs, increased $212.7 million to $527.3 million, primarily due to the acquisition of IPG.

SG&A expenses increased $106.6 million to $224.5 million, primarily due to the acquisition of IPG. Included in SG&A expenses in the first quarter of 2026 are $59.4 million of integration and transaction costs related to the acquisition of IPG.

Operating Income

Operating income increased $193.6 million to $646.2 million in the first quarter of 2026 compared to the first quarter of 2025, primarily as a result of the IPG acquisition, partially offset by costs primarily related to the integration of IPG.

Interest Expense, net

Net interest expense in the first quarter of 2026 increased $42.6 million to $72.0 million compared to the first quarter of 2025, primarily due to debt assumed as part of the IPG acquisition and the refinancing activities in

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the first quarter of 2026. Interest expense increased $59.9 million to $119.0 million. Interest income increased $17.3 million to $47.0 million.

Income Taxes

Our effective tax rate for the first quarter of 2026 was 26.9% compared to 28.5% for the first quarter of 2025. The effective tax rate for 2026 reflects the impacts of the lower tax benefit associated with integration costs, severance and repositioning charges related to the acquisition of IPG. Excluding these items, our Non-GAAP adjusted effective tax rate for the first quarter of 2026 was 26.0% compared to 26.7% for the first quarter of 2025.

Net Income – Omnicom Group Inc. and Diluted Net Income per Share

Net income - Omnicom Group Inc. for the first quarter of 2026 increased $117.5 million to $405.2 million compared to the first quarter of 2025. Weighted-average diluted shares outstanding for the first quarter of 2026 increased to 299.2 million from 198.3 million, primarily as a result of shares issued for the IPG acquisition, partially offset by net share repurchases, including shares purchased pursuant to the accelerated stock repurchase agreement. Diluted net income per share of $1.35 decreased by $0.10 from $1.45 in the prior year period.

Non-GAAP Adjusted Net Income per Share - Diluted for the first quarter of 2026 increased $0.20, or 11.8%, to $1.90 from $1.70. Non-GAAP Adjusted Net Income per Share - Diluted for the first quarters of 2026 and 2025 excluded $86.9 million and $16.1 million, respectively, of after-tax amortization expense. Non-GAAP Adjusted Net Income per Share - Diluted for the first quarter of 2026 also excluded $46.7 million of after-tax integration and transaction costs, $3.1 million of after-tax severance and repositioning costs and $27.8 million of loss on dispositions. In 2025, Non-GAAP Adjusted Net Income per Share - Diluted excluded $32.7 million of costs related to the acquisition of IPG. We present Non-GAAP Adjusted Net Income per Share - Diluted to allow for comparability with the prior year period.

EBITA

EBITA increased $289.2 million to $763.6 million in the first quarter of 2026 compared to the first quarter of 2025 and, in both periods, it included impacts from assets subsequently disposed of or currently held for sale. Adjusted EBITA increased $353.2 million, or 69.5%, to $861.4 million in the first quarter of 2026 compared to the first quarter of 2025, and the related margin stayed flat at 13.8%. EBITA and Adjusted EBITA excluded amortization expense of $117.4 million and $21.8 million in the first quarters of 2026 and 2025, respectively. Adjusted EBITA also excluded $59.4 million of costs related to the integration of IPG, severance and repositioning costs of $4.1 million, and a loss on dispositions of $34.3 million in the first quarter of 2026. Adjusted EBITA in the first quarter of 2025 also excluded $33.8 million of costs related to the acquisition of IPG.

Risks and Uncertainties

Global economic conditions and disruptions, including geopolitical events, international hostilities, acts of terrorism, public health crises, inflation or stagflation, tariffs and other trade barriers, central bank interest rate policies in countries that comprise our major markets, labor and supply chain issues affecting the distribution of our clients’ products, or a disruption in the credit markets could cause economic uncertainty and volatility. The impact of these issues on our business will vary by geographic market and discipline. We monitor economic conditions and disruptions closely, as well as client revenue levels and other factors. In response to reductions in revenue, we can take actions to align our cost structure with changes in client demand and manage our working capital. However, there can be no assurance as to the effectiveness of our efforts to mitigate any impact of the current and future adverse economic conditions and disruptions, reductions in client revenue, changes in client creditworthiness and other developments.

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Definitions - Components of Revenue Change

We use certain terms in describing the components of the change in revenue above.

Core Operations: Revenue from Core Operations excludes businesses that have been disposed of or are classified as held for sale. Amounts for 2025 are calculated on a combined basis for Omnicom and IPG.

Organic growth: calculated by subtracting the foreign exchange rate impact from total revenue growth, which is equal to the current period revenue from Core Operations minus the prior period revenue from Core Operations.

Foreign exchange rate impact on core operations: calculated by translating the current period’s local currency revenue using the prior period average exchange rates to derive current period constant currency revenue. The foreign exchange rate impact is the difference between the current period revenue in U.S. Dollars and the current period constant currency revenue.

Percentage change: Calculated by dividing the individual component amount by the prior period Core Operations revenue base.

Conference Call

Omnicom will host a conference call to review its financial results on April 28, 2026 starting at 4:30 p.m. Eastern Time. A live webcast of the call, along with the related slide presentation, will be available at Omnicom’s investor relations website, investor.omc.com, and a webcast replay will be made available after the call concludes.

About Omnicom

Omnicom (NYSE: OMC) is the world's leading marketing and sales company, built for intelligent growth in the next era. Powered by Omni and its proprietary data and identity, Omnicom's Connected Capabilities unite the company's world‑class agency brands, exceptional talent, and deep domain expertise across media, commerce, consulting, precision marketing, advertising, production, health, public relations, branding, and experiential to address clients' most critical growth priorities.For more information, visit omc.com.

Contact

Investors: Gregory Lundberg greg.lundberg@omc.com

Media: Joanne Trout joanne.trout@omc.com

Non-GAAP Financial Measures

We present financial measures determined in accordance with generally accepted accounting principles in the United States (“GAAP”) and adjustments to the GAAP presentation (“Non-GAAP”), which we believe are meaningful for understanding our performance. We believe these measures are useful in evaluating the impact of certain items on operating performance and allow for comparability between reporting periods. We define EBITA as earnings before interest, taxes, and amortization, principally of acquired intangible assets and internally developed strategic platform assets, and EBITA margin is defined as EBITA divided by revenue. We use EBITA and EBITA margin as additional operating performance measures, which exclude the non-cash amortization expense principally from acquired intangible assets and internally developed strategic platform assets. We also use Adjusted Operating Income, Adjusted Operating Income Margin, Adjusted EBITA, Adjusted EBITA Margin, Adjusted Income Tax Expense, Adjusted Net Income – Omnicom Group Inc., Adjusted Net Income per share – Omnicom Group Inc. - Diluted, and organic growth as additional operating performance measures. For 2025, we also used Combined Adjusted EBITA, which was calculated using the combined adjusted EBITA of Omnicom and IPG. Non-GAAP financial measures should not be considered in isolation from, or as a substitute for, financial information presented in accordance with GAAP. Non-GAAP financial measures as reported by us may not be comparable to similarly titled amounts reported by other companies.

Forward-Looking Statements

Certain statements in this document contain forward-looking statements, including statements within the

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meaning of the Private Securities Litigation Reform Act of 1995, as amended. In addition, from time to time, we or our representatives have made, or may make, forward-looking statements, orally or in writing. These statements may discuss goals, intentions and expectations as to future plans, trends, events, results of operations or financial condition, or otherwise, based on current beliefs of management as well as assumptions made by, and information currently available to management. Forward-looking statements may be accompanied by words such as “aim”, “anticipate”, “believe”, “plan”, “could”, “should”, “would”, “estimate”, “expect”, “forecast”, “future”, “guidance”, “intend”, “may”, “will”, “possible”, “potential”, “predict”, “project” or similar words, phrases or expressions. These forward-looking statements are subject to various risks and uncertainties, many of which are outside of our control. Therefore, you should not place undue reliance on such statements. Factors that could cause actual results to differ materially from those in the forward-looking statements include:

•international, national or local economic conditions that could adversely affect us or our clients;

•reductions in client spending, a slowdown in client payments or a deterioration or disruption in the credit markets;

•the ability to attract new clients and retain existing clients in the manner anticipated;

•changes in client marketing and communications services requirements;

•failure to manage potential conflicts of interest between or among clients;

•unanticipated changes related to competitive factors in the marketing and communications services industries;

•unanticipated changes to, or an inability to hire and retain, key personnel;

•currency exchange rate fluctuations;

•reliance on information technology systems and risks related to cybersecurity incidents;

•failure to adapt to technological developments;

•our liquidity, long-term financing needs, credit ratings and access to capital markets;

•changes in legislation or governmental regulations affecting us or our clients;

•losses on media purchases and production costs incurred on behalf of clients;

•risks associated with assumptions we make in connection with our acquisitions, critical accounting estimates and legal proceedings;

•our international operations, which are subject to the risks of currency repatriation restrictions, social or political conditions and an evolving regulatory environment in high-growth markets and developing countries;

•changes in tax rates, tax laws, regulations or interpretations, or adverse outcomes of tax audits or proceedings; and

•other business, financial, operational and legal risks and uncertainties detailed from time to time in our filings with the Securities and Exchange Commission ("SEC").

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The foregoing list of factors is not exhaustive. You should carefully consider the foregoing factors and the other risks and uncertainties that may affect our business, including those described in Item 1A., “Risk Factors” and Item 7., “Management’s Discussion and Analysis of Financial Condition and Results of Operations”, in our Annual Report on Form 10-K, in this document and in other documents filed from time to time with the SEC. Except as required under applicable law, we do not assume any obligation to update these forward-looking statements.

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OMNICOM GROUP INC. AND SUBSIDIARIES

CONSOLIDATED STATEMENTS OF INCOME

(Unaudited)

(In millions, except per share amounts)

Three Months Ended March 31,

2026 2025

Revenue $ 6,242.9 $ 3,690.4

Operating Expenses:

Salary and service costs 4,639.6 2,746.3

Occupancy and other costs 527.3 314.6

Severance and repositioning costs1

4.1 —

Loss on disposition of subsidiaries1

34.3 —

Cost of services 5,205.3 3,060.9

Selling, general and administrative expenses1

224.5 117.9

Depreciation and amortization 166.9 59.0

Total Operating Expenses1

5,596.7 3,237.8

Operating Income

646.2 452.6

Interest Expense 119.0 59.1

Interest Income 47.0 29.7

Income Before Income Taxes and Income (Loss) From Equity Method Investments 574.2 423.2

Income Tax Expense1

154.6 120.7

Income (Loss) From Equity Method Investments

(0.9) 0.9

Net Income1

418.7 303.4

Net Income Attributed To Noncontrolling Interests 13.5 15.7

Net Income - Omnicom Group Inc.1

$ 405.2 $ 287.7

Net Income Per Share - Omnicom Group Inc.:1

Basic $ 1.36 $ 1.46

Diluted $ 1.35 $ 1.45

Dividends Declared Per Common Share $ 0.80 $ 0.70

Operating income margin

10.4 % 12.3 %

Non-GAAP Measures:4

EBITA2

$ 763.6 $ 474.4

EBITA Margin2

12.2 % 12.9 %

EBITA - Adjusted1,2

$ 861.4 $ 508.2

EBITA Margin - Adjusted1,2

13.8 % 13.8 %

Non-GAAP Adjusted Net Income Per Share - Omnicom Group Inc. - Diluted1,3

$ 1.90 $ 1.70

1) See Note 3 on page 13.

2) See Note 4 on page 13 for the definition of EBITA.

3) Adjusted Net Income per Share - Diluted for the three months ended March 31, 2026 and 2025 excludes after-tax amortization expense principally from acquired intangible assets and internally developed strategic platform assets, after-tax severance and repositioning costs, after-tax loss on disposition of subsidiaries and after-tax integration and acquisition costs related to the acquisition of IPG. We believe these measures are useful in evaluating the impact of these items on operating performance and allow for comparability between reporting periods.

4) See Non-GAAP reconciliations starting on page 10.

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OMNICOM GROUP INC. AND SUBSIDIARIES

DETAIL OF OPERATING EXPENSES

(Unaudited)

(In millions)

Three Months Ended March 31,

2026 2025

Revenue $ 6,242.9 $ 3,690.4

Operating Expenses:

Salary and service costs:

Salary and related costs 3,061.6 1,780.5

Third-party service costs1

1,365.7 796.8

Third-party incidental costs2

212.3 169.0

Total salary and service costs 4,639.6 2,746.3

Occupancy and other costs 527.3 314.6

Severance and repositioning costs3

4.1 —

Loss on disposition of subsidiaries3

34.3 —

Cost of services 5,205.3 3,060.9

Selling, general and administrative expenses3

224.5 117.9

Depreciation and amortization 166.9 59.0

Total operating expenses3

5,596.7 3,237.8

Operating Income

$ 646.2 $ 452.6

1) Third-party service costs include third-party supplier costs when we act as principal in providing services to our clients.

2) Third-party incidental costs primarily consist of client-related travel and incidental out-of-pocket costs, which we bill back to the client directly at our cost and which we are required to include in revenue.

3) See Note 3 on page 12.

Page 9

OMNICOM GROUP INC. AND SUBSIDIARIES

RECONCILIATION OF NON-GAAP FINANCIAL MEASURES

(Unaudited)

(In millions)

Three Months Ended March 31,

2026 2025

Net Income - Omnicom Group Inc.

$ 405.2 $ 287.7

Net Income Attributed To Noncontrolling Interests 13.5 15.7

Net Income

418.7 303.4

Income (Loss) From Equity Method Investments

(0.9) 0.9

Income Tax Expense

154.6 120.7

Income Before Income Taxes and Income (Loss) From Equity Method Investments 574.2 423.2

Interest Expense 119.0 59.1

Interest Income 47.0 29.7

Operating Income

646.2 452.6

Add back: amortization principally from acquired intangible assets and internally developed strategic platform assets1

117.4 21.8

Earnings before interest, taxes and amortization of intangible assets (“EBITA”)1

$ 763.6 $ 474.4

Depreciation and other 49.5 37.2

EBITDA $ 813.1 $ 511.6

EBITA1

$ 763.6 $ 474.4

Severance and repositioning costs2

4.1 —

Loss on disposition of subsidiary2

34.3 —

Acquisition related costs2

59.4 33.8

EBITA - Adjusted1,2

$ 861.4 $ 508.2

Revenue $ 6,242.9 $ 3,690.4

Non-GAAP Measures:

EBITA1

$ 763.6 $ 474.4

EBITA Margin1

12.2 % 12.9 %

EBITA - Adjusted1,2

$ 861.4 $ 508.2

EBITA Margin - Adjusted1,2

13.8 % 13.8 %

1) See Note 4 on page 13.

2) See Note 3 on page 13.

The above table reconciles the Non-GAAP financial measures of EBITDA, EBITA, EBITA - Adjusted, EBITA Margin and EBITA Margin-Adjusted to the GAAP financial measure of Net Income-Omnicom Group Inc. We use EBITA and EBITA Margin as additional operating performance measures, which exclude the non-cash amortization expense principally from acquired intangible assets and internally developed strategic platform assets. Accordingly, we believe EBITA, EBITA Margin, EBITA - Adjusted, and EBITA Margin - Adjusted are useful measures for investors to evaluate the comparability of the performance of our business year to year.

Page 10

OMNICOM GROUP INC. AND SUBSIDIARIES

RECONCILIATION OF NON-GAAP FINANCIAL MEASURES - Combined

(Unaudited)

(In millions)

Three Months Ended March 31, 2025

Omnicom IPG Combined

Revenue $ 3,690.4 $ 2,322.6 $ 6,013.0

Net Income (Loss) $ 287.7 $ (85.4) $ 202.3

Net Income Attributed To Noncontrolling Interests 15.7 0.1 15.8

Net Income

303.4 (85.3) 218.1

Income (Loss) From Equity Method Investments or Unconsolidated Affiliates 0.9 (0.1) 0.8

Income Tax Expense (Benefit) 120.7 (9.2) 111.5

Income (Loss) Before Income Taxes and Income (Loss) From Equity Method Investments 423.2 (94.4) 328.8

Interest Expense 59.1 (50.1) 9.0

Interest Income 29.7 34.6 64.3

Other Expense, Net (36.9) (36.9)

Operating Income (Loss) 452.6 (42.0) 410.6

Add back: amortization principally from acquired intangible assets and internally developed strategic platform assets1

21.8 20.4 42.2

Earnings before interest, taxes and amortization of intangible assets (“EBITA”)1

$ 474.4 $ (21.6) $ 452.8

Severance and repositioning costs — 203.3 203.3

Acquisition related costs 33.8 4.8 38.6

EBITA - Adjusted1

$ 508.2 $ 186.5 $ 694.7

EBITA Margin 11.6 %

1) See Note 4 on page 13.

The above table reconciles the Non-GAAP financial measures of EBITDA, EBITA, EBITA - Adjusted, EBITA Margin and EBITA Margin- Adjusted to the GAAP financial measure of Net Income- Omnicom Group Inc. We use EBITA and EBITA Margin as additional operating performance measures, which exclude the non-cash amortization expense principally from acquired intangible assets and internally developed strategic platform assets. Accordingly, we believe EBITA, EBITA Margin, EBITA - Adjusted, and EBITA Margin - Adjusted are useful measures for investors to evaluate the comparability of the performance of our business year to year.

Page 11

OMNICOM GROUP INC. AND SUBSIDIARIES

RECONCILIATION OF NON-GAAP FINANCIAL MEASURES

(Unaudited)

(In millions)

Three Months Ended March 31,

Reported 2026

Non-GAAP Adj. (1)

Non-GAAP 2026 Adj. Reported 2025

Non-GAAP Adj. (1)

Non-GAAP 2025 Adj.

Revenue $6,242.9 $ — $ 6,242.9 $ 3,690.4 $ — $ 3,690.4

Operating Expenses1

5,596.7 (97.8) 5,498.9 3,237.8 (33.8) 3,204.0

Operating Income 646.2 97.8 744.0 452.6 33.8 486.4

Operating Income Margin 10.4 % 11.9 % 12.3 % 13.2 %

Three Months Ended March 31,

2026 2025

Net Income Net Income per Share- Diluted Net Income Net Income per Share- Diluted

Net Income - Omnicom Group Inc. - Reported

$ 405.2 $ 1.35 $ 287.7 $ 1.45

Severance and repositioning costs (after-tax)2

3.1 0.01 — —

Loss on dispositions1

27.8 0.09 — —

Acquisition related costs (after-tax)1,2

46.7 0.16 32.7 0.17

Amortization expense (after-tax)2

86.9 0.29 16.1 0.08

Non-GAAP Net Income - Omnicom Group Inc. - Adjusted2,3

$ 569.7 $ 1.90 $ 336.5 $ 1.70

1) See Note 3 on page 13.

2) Adjusted Net Income per Share - Diluted for the three months ended March 31, 2026 excludes after-tax amortization expense principally from acquired intangible assets and internally developed strategic platform assets, after-tax severance and repositioning costs, after-tax loss on disposition of subsidiaries and after-tax integration costs related to the acquisition of IPG. We believe these measures are useful in evaluating the impact of these items on operating performance and allow for comparability between reporting periods. Adjusted Net Income per Share - Diluted for the three months ended March 31, 2025 excludes after-tax amortization expense principally from acquired intangible assets and internally developed strategic platform assets and after-tax integration costs related to the acquisition of IPG.

3) Weighted-average diluted shares for the three months ended March 31, 2026 and 2025 were 299.2 million and 198.3 million, respectively. The above tables reconcile the Non-GAAP financial measures of Non-GAAP Operating Income - Adjusted, Non-GAAP Net Income-Omnicom Group Inc. - Adjusted and Non-GAAP Adjusted Net Income per Share - Diluted to the GAAP financial measures of Operating Income, Net Income - Omnicom Group Inc. and Net Income per Share - Diluted. Management believes these Non-GAAP measures are useful for investors to evaluate the comparability of the performance of our business year to year.

Page 12

NOTES:

1) Net Income and Net Income per Share for Omnicom Group Inc.

2) See Non-GAAP reconciliations starting on page 10.

3) For the three months ended March 31, 2026, operating expenses included $4.1 million ($3.1 million after-tax) of repositioning costs, primarily related to severance actions in connection with the merger (the "Merger") with IPG and $34.3 million ($27.8 million after-tax) of losses on dispositions of certain businesses in connection with the Merger. In addition, included in selling, general and administrative expenses for the three months ended March 31, 2026 are integration and transaction costs related to the acquisition of IPG of $59.4 million ($46.7 million after-tax). The net impact of these items reduced operating income for the three months ended March 31, 2026 by $97.8 million ($77.6 million after-tax), which reduced diluted net income per share - Omnicom Group Inc. by $0.26. Included in selling, general and administrative expenses for the three months ended March 31, 2025 are acquisition-related expenses of $33.8 million ($32.7 million after-tax) in connection with the Merger with IPG, which reduced diluted net income per share - Omnicom Group Inc. by $0.17.

4) We define EBITA as earnings before interest, taxes and amortization, principally of acquired intangible assets and internally developed strategic platform assets.

5) Combined (OMC + IPG) represents combined results from Omnicom and IPG as previously reported on a separate company basis during the prior year period. Combined results exclude pro-forma adjustments included in our results for Core Operations. See Note 6 below.

6) Core Operations: calculated from the consolidated revenue, adjusted operating income and adjusted EBITA of Omnicom, excluding businesses that have been disposed of or are classified as held for sale. Amounts for 2025 are calculated on a combined basis for Omnicom and IPG.

Page 13

EX-99.2

Filename: a2026q1investorpresentat.htm · Sequence: 3

a2026q1investorpresentat

April 28, 2026 2026 FIRST QUARTER

2 HIGHLIGHTS ◦ Strong momentum since closing • Strategically repositioned the portfolio for growth, sharpening our focus on the highest-growing, most connected parts of our business • New Omni platform launched across the group, integrating Acxiom's data and identity solution • Resulting in new client wins and extensions ◦ Strong revenue and profit growth from Core Operations in Q1 • +3.9% organic revenue growth • +$180 million Adj. EBITA growth • Adj. EBITA margin expansion to 14.8% from 12.4% driven primarily by synergies from the acquisition of Interpublic • On plan to meet cost reduction synergy targets ◦ Diluted EPS of $1.90 per share Non-GAAP Adjusted, an increase of 11.8% in Q1 2026 ◦ Significant capital remains available under our $5B share repurchase authorization • $2.8 billion in share repurchases in Q1 with remainder to be completed over the next 12 months

3 CORE OPERATIONS Note: Core Operations, net of dispositions and held for sale: calculated from the consolidated revenue, adjusted operating income and adjusted EBITA of Omnicom, excluding businesses that have been disposed of or are classified as held for sale. Amounts for 2025 are calculated on a combined basis for Omnicom and IPG. First Quarter 2026 2025 Omnicom Combined (OMC + IPG) 2026 Consolidated Less: Dispositions & Held for Sale Core Operations (Net of Dispositions & Held for Sale) 2025 Combined Less: Dispositions & Held for Sale Core Operations (Net of Dispositions & Held for Sale) Revenue $ 6,242.9 $ 627.2 $ 5,615.7 $ 6,013.0 $ 748.3 $ 5,264.7 Adjusted Operating Income $ 744.0 25.0 719.0 $ 652.5 36.0 616.5 Operating Income Margin % 11.9 % 4.0 % 12.8 % 10.9 % 4.8 % 11.7 % Adjusted EBITA $ 861.4 $ 27.9 $ 833.5 $ 694.7 $ 41.6 $ 653.1 EBITA Margin % 13.8 % 4.4 % 14.8 % 11.6 % 5.6 % 12.4 % In millions. See Definitions on page 11, Non-GAAP reconciliations on pages 15 - 19, and page 19 - 21 for OMC and IPG combined.

4 First Quarter Reported 2026 Non-GAAP Adjustments Non-GAAP Adj. 2026 Reported 2025 Non-GAAP Adjustments Non-GAAP Adj. 2025 Revenue $ 6,242.9 $ 6,242.9 $ 3,690.4 $ 3,690.4 Operating Expenses: Severance and repositioning costs(a) 4.1 (4.1) — — — Loss on dispositions 34.3 (34.3) — — — Selling, general and administrative(a) 224.5 (59.4) 165.1 117.9 (33.8) 84.1 Operating Expenses(a) 5,596.7 (97.8) 5,498.9 3,237.8 (33.8) 3,204.0 Operating Income(a) 646.2 97.8 744.0 452.6 33.8 486.4 Operating Income Margin % 10.4 % 11.9 % 12.3 % 13.2 % Net Interest Expense 72.0 72.0 29.4 29.4 Income Tax Expense (b) 154.6 20.2 174.8 120.7 1.1 121.8 Income Tax Rate 26.9 % 26.0 % 28.5 % 26.7 % Income (Loss) from Equity Method Investments (0.9) (0.9) 0.9 0.9 Net Income Attributed to Noncontrolling Interests 13.5 13.5 15.7 15.7 Amortization of intangible assets (after- tax) — 86.9 86.9 — 16.1 16.1 Net Income - Omnicom Group Inc.(a)(b) $ 405.2 $164.5 $ 569.7 $ 287.7 $48.8 $ 336.5 Net Income per Share - Diluted(a)(b)(5) $ 1.35 $ 1.90 $ 1.45 $ 1.70 Non-GAAP Measures: EBITA(5) $ 763.6 $97.8 $ 861.4 $ 474.4 $33.8 $ 508.2 EBITA Margin % 12.2 % 13.8 % 12.9 % 13.8 % INCOME STATEMENT SUMMARY - Reported and Non-GAAP Adjusted Ÿ In millions except per share amounts. See Definition (6), Notes on page 11, and Non-GAAP reconciliations on pages 15 - 19. Ÿ Operating expenses for the three months ended March 31, 2026 increased compared to the prior year period, primarily due to the acquisition of IPG. Amortization of acquired intangible assets are already reflected in the "Non-GAAP Adj." column of the income statement and included within reported EBITA. It is presented in the net income section to show its impact on Adjusted Net Income – Omnicom Group Inc. and Adjusted Net Income per Share – Diluted. Ÿ Weighted-average diluted shares for the three months ended March 31, 2026 and 2025 were 299.2 million and 198.3 million, respectively.

5 2026 First Quarter $ % Δ Prior period combined revenue from Core Operations $ 5,264.7 Foreign exchange rate impact 144.2 2.7 % Organic growth 206.7 3.9 % Current period revenue from Core Operations $ 5,615.6 6.7 % In millions. See Definitions (1) through (4) on page 10. Numbers may not sum due to rounding. REVENUE CHANGE Core Operations Notes: (1) Revenue from Core Operations excludes businesses that have been disposed of or are classified as held for sale. Amounts for 2025 are calculated on a combined basis for Omnicom and IPG. (2) Foreign exchange rate impact: calculated by translating the current period’s local currency revenue using the prior period average exchange rates to derive current period constant currency revenue. The foreign exchange rate impact is the difference between the current period revenue in U.S. Dollars and the current period constant currency revenue. (3) Organic growth: calculated by subtracting the foreign exchange rate impact from total revenue growth, which is equal to the current period revenue from Core Operations minus the prior period revenue from Core Operations. (4) The percentage change is calculated by dividing the individual component amount by the prior period Core Operations revenue base.

6 REVENUE BY DISCIPLINE Core Operations In millions. Numbers may not sum due to rounding. See Definition (1) on page 11. 2026 First Quarter Revenue % of Rev Integrated Media $ 2,894.3 51.5 % Advertising 943.4 16.8 % Health 535.5 9.5 % Public Relations 659.8 11.7 % Experiential & Other 582.8 10.4 % $ 5,615.7 100.0 % 52% 1 7% 1 0% 1 2% 1 0% Integrated Media Advertising Health PR Experiential & Other

7 REVENUE BY REGION Core Operations 2026 First Quarter Revenue % of Rev United States $ 3,447.8 61.4 % Other North America 177.8 3.2 % United Kingdom 492.3 8.8 % Euro Markets & Other Europe 690.0 12.3 % Asia Pacific 503.5 8.9 % Latin America 174.4 3.1 % Middle East & Africa 129.8 2.3 % 5,615.7 100.0 % In millions. Numbers may not sum due to rounding. See Definition (1) on page 11. 61 % 3% 9% 1 2% 9% 3%2% US Other North America UK Euro & Other Europe Asia Pacific Latin America Middle East & Africa

8 First Quarter 2026 2025 Omnicom Omnicom Pharma & Health 19% 15% Food & Beverage 13% 15% Auto 10% 13% Financial Services 10% 8% Consumer Products 9% 9% Retail 7% 6% Technology 7% 7% Travel & Entertainment 6% 8% Services 4% 3% Government 3% 4% Telecommunications 3% 3% Oil, Gas & Utilities 2% 2% Not-for-Profit 1% 1% Education 1% 1% Other 5% 5% Total 100% 100% REVENUE BY INDUSTRY SECTOR Note: Prior year amounts conform to the current period presentation. Amounts are calculated based on total reported Revenue.

9 CASH FLOW PERFORMANCE Three Months Ended March 31, 2026 2025 Free Cash Flow(5) $ 656.9 $ 386.5 Primary Uses of Cash: Dividends paid to Common Shareholders 251.7 137.7 Dividends paid to Noncontrolling Interest Shareholders 12.1 13.0 Capital Expenditures 61.2 29.5 Net cash paid for acquisitions, including payment of contingent purchase price obligations, and acquisition of additional noncontrolling interests 16.3 3.2 Stock Repurchases 2,777.6 81.0 Proceeds from Stock Plans (15.8) (11.5) Primary Uses of Cash(5) 3,103.1 252.9 Net Free Cash Flow(5) $ (2,446.2) $ 133.6 In millions. See Definition (5) on page 11 and Non-GAAP reconciliations on pages 15 - 19.

10 CREDIT & LIQUIDITY Twelve Months Ended March 31, 2026 2025 EBITDA(6) $ 1,022.9 $ 2,489.4 Long-Term Debt / EBITDA 9.8 x 2.5 x Net Debt(7) / EBITDA 5.6 x 1.1 x Pro Forma: (i) Total Debt / Pro forma Adj. EBITDA(i) 2.5 x Net Debt / Pro forma Adj. EBITDA(i) 1.4 x Debt Bank Loans (Due Less Than 1 Year) $ 67.4 $ 19.1 CP & Borrowings Issued Under Revolver — — USD-denominated Senior Notes 4,300.0 4,000.0 Assumed from IPG 2,950.0 EUR-denominated Senior Notes 2,532.0 1,732.2 GBP-denominated Senior Notes 430.9 420.6 Long-Term Debt, Gross $ 10,212.9 $ 6,152.8 Unamortized discount and issuance costs (235.4) (36.3) Long-Term Debt $ 9,977.5 $ 6,116.5 Cash and Equivalents 4,288.1 3,378.3 Short Term Investments — — Net Debt(7) $ 5,689.4 $ 2,738.2 In millions. See Definitions (6) and (7) on page 11 and Non-GAAP reconciliations on pages 15 - 19. (i) Pro forma Adj. EBITDA calculated according to the definition used in our credit agreement. At March 31, 2026, we were in compliance with the Leverage Ratio covenant in our credit facility.

11 NOTES (a) For the three months ended March 31, 2026, operating expenses included $4.1 million ($3.1 million after-tax) of repositioning costs, primarily related to severance actions in connection with the merger (the "Merger") with IPG and $34.3 million ($27.8 million after-tax) of losses on dispositions of certain businesses in connection with the Merger. In addition, included in selling, general and administrative expenses for the three months ended March 31, 2026 are integration and transaction costs related to the acquisition of IPG of $59.4 million ($46.7 million after-tax). The net impact of these items reduced operating income for the three months ended March 31, 2026 by $97.8 million ($77.6 million after-tax), which reduced diluted net income per share - Omnicom Group Inc. by $0.26. Included in selling, general and administrative expenses for the three months ended March 31, 2025 are acquisition-related expenses of $33.8 million ($32.7 million after-tax) in connection with the Merger with IPG, which reduced diluted net income per share - Omnicom Group Inc. by $0.17. (b) Our effective tax rate for the first quarter of 2026 was 26.9% compared to 28.5% for the first quarter of 2025.Income tax expense for the three months ended March 31, 2026 included impacts of the severance and other repositioning costs, losses on dispositions of certain business and integration and acquisition-related costs. Income tax expense for the three months ended March 31, 2025 included impacts related to real estate and other repositioning costs. (c) Third-party service costs include third-party supplier costs when we act as principal in providing services to our clients. (d) Third-party incidental costs primarily consist of client-related travel and incidental out-of-pocket costs, which we bill back to the client directly at our cost and which we are required to include in revenue. Financial Notes Definitions (1) Core operations, net of dispositions and held for sale: calculated from the combined revenue, adjusted operating income and adjusted EBITA of the Company, excluding businesses that have been disposed of or are classified as held for sale. Amounts for 2025 are calculated on a combined basis for Omnicom and IPG. (2) Foreign exchange rate impact: calculated by translating the current period’s local currency revenue using the prior period average exchange rates to derive current period constant currency revenue. The foreign exchange rate impact is the difference between the current period revenue in U.S. Dollars and the current period constant currency revenue. (3) Organic growth: calculated by subtracting the foreign exchange rate impact from total revenue growth, which is equal to the current period revenue from Core Operations minus the prior period revenue from Core Operations. (4) The percentage change is calculated by dividing the individual component amount by the prior period Core Operations revenue base. (5) See page 15 for the reconciliation of Non-GAAP financial measures, which reconciles Free Cash Flow to the Net Cash Provided by (Used in) Operating Activities and Net Free Cash Flow to the Net Decrease in Cash and Cash Equivalents for the periods presented on page 9. The Free Cash Flow, Primary Uses of Cash and Net Free Cash Flow amounts presented on page 9 are Non-GAAP liquidity measures. See page 20 for the definition of Net Free Cash Flow. (6) EBITA, EBITDA, and Non-GAAP Adjusted Net Income per share - Diluted are Non-GAAP performance measures. See page 20 for the definition of these measures and pages 16 and 19 for the reconciliation of Non-GAAP financial measures. (7) Net Debt is a Non-GAAP liquidity measure. See page 20 for the definition of this measure, which is reconciled in the table on page 10.. (8) The Free Cash Flow amounts presented on page 13 are Non-GAAP liquidity measures. See page 20 for the definition of this measure and page 15 for the reconciliation of the Non-GAAP financial measures, which reconciles Free Cash Flow to the Net Cash Provided by (Used in) Operating Activities for the periods presented on page 13.

12 APPENDIX

13 In millions. See Definition (8) on page 11 and Non-GAAP reconciliations on pages 15 - 19. Three Months Ended March 31, 2026 2025 Net Income $ 418.7 $ 303.4 Depreciation and Amortization of Intangible Assets 166.9 59.0 Share-Based Compensation 27.1 20.8 Severance and repositioning costs 4.1 — Loss on disposition of subsidiary 34.3 — Other Items to Reconcile to Net Cash Provided by (Used in) Operating Activities, net 5.8 3.3 Free Cash Flow(8) $ 656.9 $ 386.5 FREE CASH FLOW

14 OPERATING EXPENSE DETAIL First Quarter 2026 Non-GAAP Adjustments Non-GAAP Adjusted % of Rev 2025 Non-GAAP Adjustments Non-GAAP Adjusted % of Rev Revenue $ 6,242.9 $ 6,242.9 $ 3,690.4 $ 3,690.4 Operating expenses: Salary and related costs 3,061.6 3,061.6 49.0 % 1,780.5 1,780.5 48.2 % Third-party service costs(c) 1,365.7 1,365.7 21.9 % 796.8 796.8 21.6 % Third-party incidental costs(d) 212.3 212.3 3.4 % 169.0 169.0 4.6 % Total salary and service costs 4,639.6 4,639.6 74.3 % 2,746.3 2,746.3 74.4 % Occupancy and other costs 527.3 527.3 8.4 % 314.6 314.6 8.5 % Severance and repositioning costs(a) 4.1 (4.1) — — — Loss on disposition 34.3 (34.3) — — — Cost of services 5,205.3 (38.4) 5,166.9 82.8 % 3,060.9 3,060.9 82.9 % SG&A expenses(a) 224.5 (59.4) 165.1 2.6 % 117.9 (33.8) 84.1 2.3 % Depreciation and amortization 166.9 166.9 59.0 59.0 Total operating expenses 5,596.7 (97.8) 5,498.9 88.1 % 3,237.8 (33.8) 3,204.0 86.8 % Operating Income(a) $ 646.2 $ 97.8 $ 744.0 11.9 % $ 452.6 $ 33.8 $ 486.4 13.2 % Amortization 117.4 117.4 21.8 21.8 EBITA $ 763.6 $ 97.8 $ 861.4 $ 474.4 $ 33.8 $ 508.2 EBITA Margin 12.2 % 13.8 % 12.9 % 13.8 % In millions. See Notes on page 11.

15 NON-GAAP RECONCILIATIONS Three Months Ended March 31, 2026 2025 Net Cash Provided by (Used in) Operating Activities $ (553.2) $ (786.8) Operating Activities items excluded from Free Cash Flow: Changes in Operating Capital (1,210.1) (1,173.3) Free Cash Flow $ 656.9 $ 386.5 Net Decrease in Cash and Cash Equivalents $ (2,593.0) $ (961.1) Cash Flow items excluded from Net Free Cash Flow: Changes in Operating Capital (1,210.1) (1,173.3) Proceeds from borrowings 2,384.9 — Repayment of Long-term Debt (1,400.0) — Proceeds from assets held for sale 152.5 — Other investing, net (7.1) 42.2 Changes in Short-term Debt, net 7.4 (3.2) Other financing, net (15.7) (14.8) Effect of foreign exchange rate changes on cash and cash equivalents (58.7) 54.4 Net Free Cash Flow $ (2,446.2) $ 133.6 Twelve Months Ended March 31, 2026 2025 Reported Operating Income $ 638.3 $ 2,248.3 Effective Tax Rate for the applicable period 64.3 % 26.9 % Income Taxes on Reported Operating Income 410.4 604.8 After Tax Reported Operating Income $ 227.9 $ 1,643.5 In millions.

16 NON-GAAP RECONCILIATIONS In millions. See Definition (5) and Notes on page 11. The above table reconciles to the Non-GAAP financial measures of EBITDA, EBITA, and EBITA - Adjusted to the GAAP financial measures of Net Income - Omnicom Group Inc. for the periods presented. See page 20 for definition of Non-GAAP financial measures. First Quarter 2026 2025 Net Income - Omnicom Group Inc.(a)(b) $ 405.2 $ 287.7 Net Income Attributed to Noncontrolling Interests 13.5 15.7 Income (Loss) From Equity Method Investments (0.9) 0.9 Income Tax Expense 154.6 120.7 Income Before Income Taxes and Income (Loss) From Equity Method Investments 574.2 423.2 Net Interest Expense 72.0 29.4 Operating Income(a)(b) 646.2 452.6 Amortization principally from acquired intangible assets and internally developed strategic platform assets 117.4 21.8 EBITA(5) 763.6 474.4 Other Amortization — 4.0 Depreciation 49.5 33.2 EBITDA(5) $ 813.1 $ 511.6 EBITA(5) $ 763.6 $ 474.4 Severance and repositioning costs(a) 4.1 — Loss on disposition of subsidiary(a) 34.3 — Acquisition related costs(a) 59.4 33.8 EBITA - Adjusted(5) $ 861.4 $ 508.2 Revenue $ 6,242.9 $ 3,690.4 EBITA(5) $ 763.6 $ 474.4 EBITA Margin % 12.2 % 12.9 % EBITA - Adjusted(a)(5) $ 861.4 $ 508.2 EBITA Margin % - Adjusted(a) 13.8 % 13.8 %

17 NON-GAAP RECONCILIATIONS - 2025 COMBINED In millions. See Definition (6) and Notes on page 11. The above table reconciles to the Non-GAAP financial measures of EBITDA, EBITA, and EBITA - Adjusted to the GAAP financial measures of Net Income - Omnicom Group Inc. for the periods presented. See page 20 for definition of Non-GAAP financial measures. First Quarter 2025 OMC IPG COMBINED Net Income (Loss) $ 287.7 $ (85.4) Net Income Attributed to Noncontrolling Interests $ 15.7 $ 0.1 Income (Loss) From Equity Method Investments 0.9 (0.1) Income Tax Expense (Benefit) 120.7 (9.2) Income Before Income Taxes and Income (Loss) From Equity Method Investments 423.2 (94.4) Net Interest Expense 29.4 15.5 Other Expense, Net 36.9 Operating Income 452.6 (42.0) Severance and repositioning costs — 203.3 Acquisition related costs 33.8 4.8 Adjusted Operating Income 486.4 166.1 652.5 Operating Income % 10.9 % Amortization principally from acquired intangible assets and internally developed strategic platform assets 21.8 20.4 EBITA - Adjusted(6) 508.2 186.5 694.7 EBITA Margin % 11.6 % Revenue $ 3,690.4 $ 2,322.6 6,013.0

18 NON-GAAP RECONCILIATIONS In millions. See Notes on page 11. The above table reconciles the adjusted Non-GAAP financial measure of Non-GAAP Operating Income - Adjusted to the GAAP financial measure of Operating Income for the periods presented. Management believes excluding the acquisition related costs and repositioning costs is useful for investors to evaluate the comparability of the performance of our business between reporting periods. First Quarter 2026 2025 Net Income - Omnicom Group Inc.- Reported $ 405.2 $ 287.7 Net Income Attributed To Noncontrolling Interests 13.5 15.7 Net Income 418.7 303.4 Income (Loss) From Equity Method Investments (0.9) 0.9 Income Tax Expense(b) 154.6 120.7 Income Before Income Taxes and Income (Loss) From Equity Method Investments 574.2 423.2 Net Interest Expense 72.0 29.4 Operating Income - Reported 646.2 452.6 Severance and repositioning costs(a) 4.1 — Loss on disposition of subsidiary(a) 34.3 — Acquisition related costs(a) 59.4 33.8 Non-GAAP Operating Income - Adjusted $ 744.0 $ 486.4

19 First Quarter 2026 2025 Net Income - Omnicom Group Inc. - Reported $ 405.2 $ 287.7 Impact on Net Income related to: Severance and Repositioning costs(a) 3.1 — Loss on dispositions(a) 27.8 Acquisition related costs(a) 46.7 32.7 Amortization principally from acquired intangible assets and internally developed strategic platform assets 86.9 16.1 Non-GAAP Net Income - Omnicom Group Inc. - Adjusted(5) $ 569.7 $ 336.5 Diluted Shares 299.2 198.3 Reported Net Income (Loss) per Share - Diluted 1.35 1.45 Severance and repositioning costs(a) 0.01 0.00 Loss on dispositions(a) 0.09 0.00 Acquisition related costs(a) 0.16 0.17 Amortization expense 0.29 0.08 Non-GAAP Adjusted Net Income per Share - Omnicom Group Inc. - Diluted (5) $ 1.90 $ 1.70 NON-GAAP RECONCILIATIONS In millions. See Definition (5) and Notes on page 11. The above table reconciles the adjusted Non-GAAP financial measures of Non-GAAP Net Income-Omnicom Group Inc.-Adjusted and Non-GAAP Adjusted Net Income per Share - Omnicom Group Inc. - Diluted to the GAAP financial measures of Net Income - Omnicom Group Inc. and Net income per share - Omnicom Group Inc. - diluted for the periods presented. Management believes these Non-GAAP measures are useful for investors to evaluate the comparability of the performance of our business between reporting periods.

20 DISCLOSURES The preceding materials have been prepared for use in the April 28, 2026 conference call on Omnicom’s results of operations for the three months ended March 31, 2026. The call will be archived on the internet at http://investor.omc.com Forward-Looking Statements Certain statements in this document contain forward-looking statements, including statements within the meaning of the Private Securities Litigation Reform Act of 1995, as amended. In addition, from time to time, we or our representatives have made, or may make, forward-looking statements, orally or in writing. These statements may discuss goals, intentions and expectations as to future plans, trends, events, results of operations or financial condition, or otherwise, based on current beliefs of management as well as assumptions made by, and information currently available to management. Forward-looking statements may be accompanied by words such as “aim”, “anticipate”, “believe”, “plan”, “could”, “should”, “would”, “estimate”, “expect”, “forecast”, “future”, “guidance”, “intend”, “may”, “will”, “possible”, “potential”, “predict”, “project” or similar words, phrases or expressions. These forward-looking statements are subject to various risks and uncertainties, many of which are outside of our control. Therefore, you should not place undue reliance on such statements. Factors that could cause actual results to differ materially from those in the forward-looking statements include: risks relating to the completed merger (the “Merger”) between us and The Interpublic Group of Companies, Inc. ("IPG"), including risks related to the integration of IPG’s business, such as, among others: uncertainties associated with retaining key management and other employees; potential disruptions to client, vendor, and business partner relationships; the risk that integration activities may be more time-consuming, complex, or costly than expected; the possibility that anticipated synergies, efficiencies, and other benefits of the Merger may not be realized, or may be realized more slowly than anticipated; and risks associated with managing a larger, more complex combined organization and effectively integrating systems, processes, operations, and cultures; adverse economic conditions, including geopolitical events, international hostilities, acts of terrorism, public health crises, inflation or stagflation, tariffs and other trade barriers, central bank interest rate policies in countries that comprise our major markets, labor and supply chain issues affecting the distribution of our clients’ products, or a disruption in the credit markets; international, national or local economic conditions that could adversely affect us or our clients; reductions in client spending, a slowdown in client payments or a deterioration or disruption in the credit markets; the ability to attract new clients and retain existing clients in the manner anticipated; changes in client marketing and communications services requirements; failure to manage potential conflicts of interest between or among clients; unanticipated changes related to competitive factors in the marketing and communications services industries; unanticipated changes to, or an inability to hire and retain, key personnel; currency exchange rate fluctuations; reliance on information technology systems and risks related to cybersecurity incidents; effective management of the risks, challenges and efficiencies presented by utilizing artificial intelligence, or AI, technologies and related partnerships in our business, and their use by our competitors; failure to adapt to technological developments; our liquidity, long-term financing needs, credit ratings and access to capital markets; changes in legislation or governmental regulations affecting us or our clients; losses on media purchases and production costs incurred on behalf of clients; risks associated with assumptions we make in connection with our acquisitions, critical accounting estimates and legal proceedings; Our international operations, which are subject to the risks of currency repatriation restrictions, social or political conditions and an evolving regulatory environment in high-growth markets and developing countries; risks related to our environmental, social and governance goals and initiatives, including impacts from regulators and other stakeholders, and the impact of factors outside of our control on such goals and initiatives; changes in tax rates, tax laws, regulations or interpretations, or adverse outcomes of tax audits or proceedings; and other business, financial, operational and legal risks and uncertainties detailed from time to time in our filings with the Securities and Exchange Commission ("SEC"). The foregoing list of factors is not exhaustive. You should carefully consider the foregoing factors and the other risks and uncertainties that may affect our business, including those described in Item 1A., “Risk Factors” and Item 7., “Management’s Discussion and Analysis of Financial Condition and Results of Operations,” in our Annual Report on Form 10-Kand in other documents filed from time to time with the SEC. Except as required under applicable law, we do not assume any obligation to update these forward-looking statements. Non-GAAP Financial Measures We present financial measures determined in accordance with generally accepted accounting principles in the United States (“GAAP”) and adjustments to the GAAP presentation (“Non-GAAP”), which we believe are meaningful for understanding our performance. We believe these measures are useful in evaluating the impact of certain items on operating performance and allow for comparability between reporting periods. EBITA is defined as earnings before interest, income taxes, and amortization, principally from acquired intangible assets and internally developed strategic platform assets, and EBITA margin is defined as EBITA divided by revenue. We use EBITA and EBITA margin as additional operating performance measures, which exclude the non-cash amortization expense of acquired intangible assets and internally developed strategic platform assets. We also use Adjusted Operating Income, Adjusted Operating Income Margin, Adjusted EBITA, Adjusted EBITA Margin, Adjusted Income Tax Expense, Adjusted Net Income – Omnicom Group Inc. and Adjusted Net Income per diluted share – Omnicom Group Inc. as additional operating performance measures. Free Cash Flow is defined as net income plus depreciation, amortization, share based compensation expense plus/(less) other items to reconcile to net cash (used in) provided by operating activities. We believe Free Cash Flow is a useful measure of liquidity to evaluate our ability to generate excess cash from our operations. Primary Uses of Cash is defined as dividends to common shareholders, dividends paid to non-controlling interest shareholders, capital expenditures, cash paid on acquisitions, payments for additional interest in controlled subsidiaries and stock repurchases, net of the proceeds from our stock plans, and excludes changes in operating capital and other investing and financing activities, including commercial paper issuances and redemptions used to fund working capital changes. We believe this liquidity measure is useful in identifying the significant uses of our cash. Net Free Cash Flow is defined as Free Cash Flow less the Primary Uses of Cash. Net Free Cash Flow is one of the metrics used by us to assess our sources and uses of cash and was derived from our consolidated statements of cash flows. We believe that this liquidity measure is meaningful for understanding our primary sources and primary uses of that cash flow. EBITDA is defined as earnings before interest, taxes, depreciation and amortization of intangible assets. Net Debt is defined as total debt less cash, cash equivalents and short-term investments. We believe net debt, together with the comparable GAAP measures, reflects one of the liquidity metrics used by us to assess our cash management. Non- GAAP financial measures should not be considered in isolation from, or as a substitute for, financial information presented in accordance with GAAP. Non-GAAP financial measures as reported by us may not be comparable to similarly titled amounts reported by other companies. Other Information All dollar amounts are in millions except for per share figures. The information contained in this document has not been audited, although some data has been derived from Omnicom’s historical financial statements, including its audited financial statements. In addition, industry, operational, and other non-financial data contained in this document have been derived from sources that we believe to be reliable, but we have not independently verified such information, and we do not, nor does any other person, assume responsibility for the accuracy or completeness of that information. Certain amounts in prior periods have been reclassified to conform to our current presentation. The inclusion of information in this presentation does not mean that such information is material or that disclosure of such information is required.

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