Form 8-K

8-K — Soluna Holdings, Inc

Accession: 0001493152-26-013710

Filed: 2026-03-31

Period: 2026-03-29

CIK: 0000064463

SIC: 6199 (FINANCE SERVICES)

Item: Changes in Registrant's Certifying Accountant

Item: Financial Statements and Exhibits

Documents

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UNITED

STATES

SECURITIES

AND EXCHANGE COMMISSION

Washington,

D.C. 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): March

29, 2026

SOLUNA

HOLDINGS, INC.

(Exact

name of registrant as specified in its charter)

Nevada

001-40261

14-1462255

(State

or Other Jurisdiction

Incorporation)

(Commission

File

Number)

(IRS

Employer

Identification

No.)

325

Washington Avenue Extension

Albany,

New York

12205

(Address

of principal executive offices)

(Zip

Code)

Registrant’s

Telephone Number, Including Area Code: (516) 216-9257

N/A

(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(see General Instruction A.2. below):

☐

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(s)

Name

of exchange on which registered

Common

Stock, par value $0.001 per share

SLNH

The

Nasdaq Stock Market LLC

9.0%

Series A Cumulative Perpetual Preferred Stock, par value $0.001 per share

SLNHP

The

Nasdaq Stock Market LLC

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 ☐

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

4.01. Changes in Registrant’s Certifying Accountant.

(a)

Dismissal of Independent Registered Public Accounting Firm.

March 29, 2026, Soluna Holdings, Inc. (the “Company”) notified UHY LLP (“UHY”) that UHY would be dismissed as

the Company’s independent registered public accounting firm. The Audit Committee of the Board of Directors of the Company (the

“Audit Committee”) approved the decision to dismiss UHY, which will become effective on March 29, 2026.

The

audit reports of UHY on the Company’s financial statements as of and for the fiscal years ended December 31, 2025 and 2024 did

not contain an adverse opinion or a disclaimer of opinion, and were not qualified or modified as to uncertainty, audit scope, or accounting

principles.

During

the Company’s two most recent fiscal years ended December 31, 2025 and 2024, and through March 29, 2026, the Company has not had

any disagreement with UHY on any matter of accounting principles or practices, financial statement disclosure or auditing scope or procedures,

which disagreement, if not resolved to UHY’s satisfaction, would have caused UHY to make reference to the subject matter of the

disagreement in its reports on the Company’s financial statements. In addition, during the Company’s two most recent fiscal

years ended December 31, 2025 and 2024, and through March 29, 2026, there were no “reportable events” as that term is defined

in Item 304(a)(1)(v) of Regulation S-K.

The

Company provided UHY with a copy of this Current Report on Form 8-K prior to its filing with the Securities and Exchange Commission (“SEC”)

and requested that UHY furnish it with a letter addressed to the SEC stating whether or not it agrees with the above statements in this

Item 4.01(a). A copy of UHY’s letter, dated March 30, 2026, is filed as Exhibit 16.1 to this Current Report on Form 8-K.

(b)

Appointment of New Independent Registered Public Accounting Firm.

March 29, 2026, the Audit Committee approved the appointment of KPMG LLP (“KPMG”) as the Company’s new independent

registered public accounting firm for the fiscal year ended December 31, 2026.

During

the fiscal years ended December 31, 2025 and 2024 and the subsequent interim period through March 29, 2026, neither the Company nor anyone

acting on its behalf consulted KPMG on any matter relating to either (i) the application of accounting principles to a specific transaction,

either completed or contemplated, or the type of audit opinion that might be rendered on the Company’s financial statements or

(ii) any matter that was the subject of a disagreement (as that term is defined in Item 304(a)(1)(iv) of Regulation S-K and the related

instructions) or a “reportable event” (as that term is defined in Item 304(a)(1)(v) of Regulation S-K).

Item

9.01. Financial Statements and Exhibits.

(d)

Exhibits

Exhibit

No.

Description

16.1

Letter to Securities and Exchange Commission from UHY LLP, dated March 30, 2026

104

Cover

Page Interactive Data File (embedded within the Inline XBRL document)

SIGNATURE

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.

SOLUNA

HOLDINGS, INC.

Dated:

March 30, 2026

By:

/s/

David Michaels

Name:

David

Michaels

Title:

Chief Financial Officer

(principal financial officer)

EX-16.1

Filename: ex16-1.htm · Sequence: 2

Exhibit

16.1

March

30, 2026

Securities

and Exchange Commission

100

F Street, N.E.

Washington,

DC 20549

Commissioners:

have read Item 4.01 of Form 8-K filed with the U.S. Securities and Exchange Commission on March 30, 2026 of Soluna Holdings, Inc. (the

“Company”) and are in agreement with the statements contained in (a) (Dismissal of Independent Registered Public Accounting

Firm). We have no basis to agree or disagree with other statements of the Company contained therein.

/s/

UHY LLP

Albany,

New York

March

30, 2026

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Entity Registrant Name

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HOLDINGS, INC.

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Entity Tax Identification Number

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Entity Incorporation, State or Country Code

Entity Address, Address Line One

325

Washington Avenue Extension

Entity Address, City or Town

Albany

Entity Address, State or Province

Entity Address, Postal Zip Code

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City Area Code

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Local Phone Number

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Security Exchange Name

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9.0% Series A Cumulative Perpetual Preferred Stock, par value $0.001 per share

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SLNHP

Security Exchange Name

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