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): ~~February~~March 202, 2026

WESTERN ALLIANCE BANCORPORATION

(Exact name of registrant as specified in its charter)

Delaware

001-32550

88-0365922

(State or other jurisdiction
of incorporation)

(Commission
File Number)

(IRS Employer
Identification No.)

One E. Washington Street, Phoenix, Arizona 85004

(Address of principal executive offices) (Zip Code)

(602) 389-3500

(Registrant's telephone number, including area code)

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(s)

Name of each exchange on which registered

Common Stock, $0.0001 Par Value

WAL

New York Stock Exchange

Depositary Shares, Each Representing a 1/400th Interest in a Share of

4.250% Fixed-Rate Reset Non-Cumulative Perpetual Preferred Stock, Series A

WAL PrA

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 82.0106. ~~OTHER~~MATERIAL ~~EVENTS.~~IMPAIRMENTS

~~2026~~Western ~~Investor~~Alliance ~~Day~~Bancorporation ~~Announcement~~(the “Company”) was recently informed that the counterparties to a commercial loan facility and forbearance agreement with Western Alliance Bank (the “Bank”) would not make a $42.125 million principal payment required pursuant to those agreements and would also discontinue future payments.

~~Western~~On ~~Alliance~~March ~~Bancorporation~~2, (2026, the “Company”) ~~today~~concluded ~~announced~~that ~~plans~~a tomaterial ~~host~~charge anfor ~~Investor~~impairment ~~Day~~would result from notification of this breach of contract. The outstanding balance on ~~Tuesday,~~this ~~May~~loan ~~12,~~is ~~2026~~$126.4 inmillion. ~~New~~Based ~~York,~~on NYcurrently available information, the non-cash impairment charge associated with ~~presentations~~this byfacility, which will be recognized in the ~~Company’s~~first ~~management~~quarter ~~team~~of 2026, will be $126.4 million.

AThe ~~live~~Bank ~~webcast~~has ~~and~~asserted ~~associated~~claims ~~materials~~against ~~will~~the becounterparties ~~accessible~~and ~~via~~affiliated ~~Western~~entities ~~Alliance’s~~to ~~Investor~~recover ~~Relations~~these ~~website~~funds, ~~at:~~plus ~~https://investors.westernalliancebancorporation.com~~fees, onexpenses, ~~the~~and ~~Events~~related &damages, ~~Presentations~~and ~~page.~~will Apursue ~~replay~~all ~~will~~of ~~also~~its belegal ~~available~~rights and remedies.

~~Additional~~ITEM ~~details,~~7.01. ~~including~~REGULATION ~~dial-in~~FD ~~information, will be available on the Investor Relations website referenced above closer to the event date.~~DISCLOSURE

On March 6, 2026, the Company issued a press release addressing its response to a counterparty default resulting in a material impairment.

The information in this Item 7.01 of this Current Report on Form 8-K, including Exhibit 99.1 attached hereto, is being furnished and shall not be deemed “filed” for the purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), or otherwise subject to the liabilities of that Section, nor shall it be deemed subject to the requirements of amended Item 10 of Regulation S-K, nor shall it be deemed incorporated by reference into any filing of the Company under the Securities Act of 1933, as amended, or the Exchange Act, whether made before or after the date hereof, regardless of any general incorporation language in such filing. The furnishing of this information hereby shall not be deemed an admission as to the materiality of any such information.

Forward-Looking Statements

Certain statements contained in this current report on Form 8-K (this “Form 8-K”) are “forward-looking statements” within the meaning of the Private Securities Litigation Reform Act of 1995 (the “Reform Act”), including those related to the potential recovery of funds. These forward-looking statements reflect the Company’s current views about future events and financial performance and involve certain risks, uncertainties, assumptions, and changes in circumstances that may cause the Company’s actual results to differ significantly from historical results and those expressed in any forward-looking statement. Factors that may cause actual results to differ materially from those contemplated by such forward-looking statements include, but are not limited to, matters to be determined in certain legal proceedings and the amount of funds and/or collateral available for repayment of the facility, as well as those described in “Risk Factors” in Item 1A of the Company’s Annual Report on Form 10-K for the fiscal year ended December 31, 2025. Forward-looking statements speak only as of the date they are made and the Company undertakes no obligation to publicly update or revise any forward-looking statements included in this Form 8-K or to update the reasons why actual results could differ from those contained in such statements, whether as a result of new information, future events or otherwise, except to the extent required by federal securities laws. In light of these risks, uncertainties and assumptions, the forward-looking events discussed in this Form 8-K might not occur, and you should not put undue reliance on any forward-looking statements.

ITEM 9.01. FINANCIAL STATEMENTS AND EXHIBITS.

(d) Exhibits.

99.1						Press Release dated ~~February~~March 206, 2026
104						Cover Page Interactive Data File (embedded within the Inline XBRL document)

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.

			WESTERN ALLIANCE BANCORPORATION
			(Registrant)
			/s/ Vishal Idnani
			Vishal Idnani
			Chief Financial Officer
Date:			~~February~~March 206, 2026

Filing Compare · WESTERN ALLIANCE BANCORPORATION