Form 8-K/A

8-K/A — American Water Works Company, Inc.

Accession: 0001410636-26-000113

Filed: 2026-07-06

Period: 2026-07-01

CIK: 0001410636

SIC: 4941 (WATER SUPPLY)

Item: Other Events

Item: Financial Statements and Exhibits

Documents

8-K/A — awk-20260701.htm (Primary)

EX-99.1 — EX-99.1 PRESS RELEASE OF MISSOURI AMERICAN WATER (exhibit991-mawcpressreleas.htm)

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8-K/A — FORM 8-K/A - MISSOURI-AMERICAN WATER GENERAL RATE CASE FILING

8-K/A (Primary)

Filename: awk-20260701.htm · Sequence: 1

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July 1, 20260001410636true00014106362026-07-012026-07-01

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

Form 8-K/A

Amendment No. 1

Current Report

Pursuant to Section 13 or 15(d)

of the Securities Exchange Act of 1934

Date of Report (Date of earliest event reported): July 1, 2026

American Water Works Company, Inc.

(Exact name of registrant as specified in its charter)

Commission File Number: 001-34028

Delaware 51-0063696

(State or other jurisdiction

of incorporation) (IRS Employer

Identification No.)

1 Water Street

Camden, NJ 08102-1658

(Address of principal executive offices, including zip code)

(856) 955-4001

(Registrant’s telephone number, including area code)

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 $0.01 per share AWK 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 (17 CFR 230.405) or Rule 12b-2 of the Securities Exchange Act of 1934 (17 CFR 240.12b-2).

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. ☐

EXPLANATORY NOTE

American Water Works Company, Inc. is filing this amendment to its Current Report on Form 8-K originally filed with the Securities and Exchange Commission on July 1, 2026 (the “Original Form 8-K”), solely to correct the “document period end date” element of the Original Form 8-K’s cover page XBRL tags, provided as noted below under Exhibit 104, which inadvertently referenced an incorrect date. No other changes have been made to the disclosures contained in Items 8.01 and 9.01 of the Original Form 8-K or Exhibit 99.1 thereto.

Item 8.01. Other Events.

Filing of Rate Request with the Missouri Public Service Commission (the “MoPSC”) by Missouri-American Water Company (“Missouri American Water”)

On July 1, 2026, Missouri American Water, a wholly owned subsidiary of American Water Works Company, Inc. (the “Company”), announced that it filed with the MoPSC a request for new water and wastewater rates. The request seeks annualized incremental revenue of approximately $179 million, excluding infrastructure surcharges of approximately $32 million, of which $18 million remains subject to approval. The request is based on a return on equity of 10.50% and a capital structure with an equity component of 50.3% and a long-term debt component of 49.7%. The requested annualized incremental revenue is driven primarily by approximately $1.6 billion of incremental capital investments completed and planned by Missouri American Water from June 2025 through May 2028, the forecasted future test period. Missouri American Water anticipates that new rates will take effect in June 2027. Pursuant to statutory requirements, Missouri American Water will implement subsequent rate adjustments following the conclusion of the future test year based on required reconciliations, subject to regulatory approval.

A copy of the press release issued by Missouri American Water on July 1, 2026, has been filed as Exhibit 99.1 hereto and is incorporated herein by reference. References and links to websites and other information contained in this press release are not provided as active hyperlinks, and the information contained in or accessed through these hyperlinks shall not be incorporated into, or form a part of, this Current Report on Form 8-K.

Cautionary Statement Concerning Forward-Looking Statements

Certain statements included in this Current Report on Form 8-K (or the exhibit thereto) are forward-looking statements within the meaning of Section 27A of the Securities Act of 1933, Section 21E of the Securities Exchange Act of 1934, and the Private Securities Litigation Reform Act of 1995. In some cases, these forward-looking statements can be identified by words with prospective meanings such as “intend,” “plan,” “estimate,” “believe,” “anticipate,” “expect,” “predict,” “project,” “propose,” “assume,” “forecast,” “outlook,” “future,” “pending,” “goal,” “objective,” “potential,” “continue,” “seek to,” “may,” “can,” “will,” “should” and “could,” or the negative of such terms or other variations or similar expressions. These forward-looking statements are predictions based on the Company’s current expectations and assumptions regarding future events. They are not guarantees or assurances of any outcomes, performance or achievements, and readers are cautioned not to place undue reliance upon them. The forward-looking statements are subject to a number of estimates and assumptions, and known and unknown risks, uncertainties and other factors. Actual results may differ materially from those discussed in the forward-looking statements included in this Current Report on Form 8-K as a result of the factors discussed in the Company’s Annual Report on Form 10-K for the year ended December 31, 2025, as filed with the Securities and Exchange Commission (the “SEC”) on February 18, 2026, and other filings with the SEC, and additional risks and uncertainties, including with respect to (1) the terms of any settlement agreement or stipulation, and/or final order of the MoPSC, with respect to the above-referenced general rate case; (2) the timing of the implementation of new rates under the general rate case; (3) the amount and timing of incremental capital investments to be completed by Missouri American Water; (4) regulatory, legislative, local or municipal actions affecting the water and wastewater industries, which could adversely affect the Company and/or Missouri American Water; and (5) other economic, financial, political, business and other factors that may impact or affect the water and wastewater industries generally or the Company or Missouri American Water specifically.

These forward-looking statements are qualified by, and should be read together with, the risks and uncertainties set forth above and the risk factors included in the Company’s annual and quarterly reports as filed with the SEC, and readers should refer to such risks, uncertainties and risk factors in evaluating such forward-looking statements. Any forward-looking statements speak only as of the date of this Current Report on Form 8-K. The Company does not have any obligation or intention to update or revise any forward-looking statement, whether as a result of new information, future events, changed circumstances or otherwise, except as otherwise required by the federal securities laws. New factors emerge from time to time, and it is not possible for the Company to predict all such factors. Furthermore, it may not be possible to assess the impact of any

such factor on the Company’s or Missouri American Water’s business, either viewed independently or together, or the extent to which any factor, or combination of factors, may cause results to differ materially from those contained in any forward-looking statement.

Item 9.01. Financial Statements and Exhibits.

(d) Exhibits.

The following exhibits to this Current Report have been provided herewith as noted below:

Exhibit No. Description

99.1*

Press Release, dated July 1, 2026, issued by Missouri American Water.

104 Cover Page Interactive Data File (the cover page XBRL tags are included and formatted as Inline XBRL).

* Filed herewith.

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.

AMERICAN WATER WORKS COMPANY, INC.

Dated: July 6, 2026 By: /s/ DAVID M. BOWLER

David M. Bowler

Executive Vice President and Chief Financial Officer

EX-99.1 — EX-99.1 PRESS RELEASE OF MISSOURI AMERICAN WATER

EX-99.1

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Document

Exhibit 99.1

Missouri American Water Files Rate Request Driven by Approximately $1.6 Billion in Investments to Provide Safe, Clean, Reliable and Affordable Service

Request supports continued infrastructure investments in water and wastewater

systems serving more than 1.7 million people in 30 counties

ST. LOUIS, MO., July 1, 2026 – Missouri American Water today filed a request with the Missouri Public Service Commission (MoPSC) for new rates to support approximately $1.6 billion in water and wastewater system investments from June 2025 through May 2028. The request reinforces the company's commitment to implementing critical system upgrades and continuing to improve water quality and reliability for its more than 1.7 million people served statewide.

“We strategically plan and invest in our water and wastewater systems to help ensure they continue meeting the needs of our customers and communities,” said Rich Svindland, President of Missouri American Water. “These investments strengthen service reliability and enhance water quality—from treatment to tap—while reflecting our employees’ ongoing commitment to the health and safety of the communities we proudly serve.”

The proposed rate change will support the company's continuing infrastructure investments from June 2025 to May 2028 to modernize and strengthen its water and wastewater systems in communities across Missouri. These investments will include the replacement of approximately 140 miles of aging water and wastewater pipeline, upgrading of storage tanks, wells, pumping stations, hydrants, meters and wastewater plants, as well as ongoing replacement of lead service lines and improvements to treatment facilities to address regulatory requirements, including PFAS and other contaminants of emerging concern.

Investments include:

•St. Louis County: The relocation and replacement of the South Plant intake at a higher elevation mitigates flood risk, while raw water pump replacements, emergency power generation and replacement of aging pump components improve operating efficiency and reduce service disruptions during extreme weather.

•Jefferson City: Construction of a new filter and chemical feed building renews critical infrastructure past its useful life and enhances water quality and treatment efficiency.

•St. Joseph: Water treatment plant expansion including a new clarifier and filters, rehabilitation of treatment units and upgrades to chemical feed system improves service reliability, safety, and efficiency.

•Joplin: Construction of a new carbon feed system, well site treatment upgrades and filter backwash improvements will increase safety and help maintain consistent water quality and service reliability.

•Wastewater Treatment Investments: Treatment equipment upgrade, lift station construction and treatment enhancements will improve treatment reliability and efficiency, while helping to meet environmental compliance.

If the company’s proposed rates are approved as filed with the MoPSC today, the water bill for the average residential customer in St. Louis County using 5,900 gallons per month would increase by approximately $23 per month. The water bill for the average residential customer outside of St. Louis County using 4,500 gallons per month would increase by about $15 per month. The request updates residential wastewater rates to support continued investment with modest increases for lower usage customers and larger adjustments that help align higher-usage and unmetered customers with the cost of service.

Missouri American Water remains committed to affordability and offers programs to assist income-eligible customers, including its H2O Help to Others assistance program, budget billing options and flexible payment plans. More details can be found on the company’s customer service webpage.

To learn more about Missouri American Water's rate filing, click here. To learn more about pipe replacement projects in your community, visit missouriamwater.com > News & Community > Public Maps > Pipe Replacement Map.

The rate request is the first step in an extensive MoPSC review process that can take up to 11 months. Customers will have multiple opportunities to provide input, including submitting written comments and attending public input hearings scheduled by the MoPSC. All rate changes require MoPSC approval. If approved, the company’s new rates could take effect in June 2027.

About American Water

American Water (NYSE: AWK) is the largest regulated water and wastewater utility company in the United States. With a history dating back to 1886 and celebrating 140 years in 2026, We Keep Life Flowing® by providing safe, clean, reliable and affordable drinking water and wastewater services to approximately 14 million people with regulated operations in 14 states and on 18 military installations. American Water’s approximately 7,000 talented professionals leverage their significant expertise and the company’s national size and scale to achieve excellent outcomes for the benefit of customers, employees, investors and other stakeholders.

For more information, visit amwater.com and join American Water on LinkedIn, Facebook, X and Instagram.

About Missouri American Water

Missouri American Water, a subsidiary of American Water, is the largest regulated water utility in the state with over 700 dedicated employees working to provide safe, clean, reliable and affordable water and wastewater services to approximately 1.7 million people. For more, visit missouriamwater.com and follow Missouri American Water on X, Facebook, Instagram, YouTube and LinkedIn.

AWK-IR

Media Contact:

Christie Barnhart

Senior Manager, External Communications

Missouri American Water

Christie.barnhart@amwater.com

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