6-K

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, DC 20549

FORM 6-K

REPORT OF FOREIGN PRIVATE ISSUER PURSUANT TO RULE 13a-16 OR 15d-16 UNDER THE SECURITIES EXCHANGE ACT OF 1934

February 28,2023

Commission FileNumber 1-10167

WESTPAC BANKING CORPORATION

(Translation of registrant’s name into English)

275 KENT STREET, SYDNEY, NEW SOUTH WALES 2000, AUSTRALIA

(Address of principal executive office)

Indicate by check mark whether the registrant files or will file annual reports under cover of Form 20-F or Form 40-F.

Form 20-F    x              Form 40-F     ¨

Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101(b)(1): ¨

Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101(b)(7): ¨

Incorporation by Reference

The information contained in this Report on Form 6-K, excluding the information set forth in Exhibit 1, shall be incorporated by reference in the prospectuses relating to the Registrant’s securities contained in the Registrant’s Registration Statements on Form F-3 (File Nos. 333-260702 and 333-260703), as such prospectuses may be amended or supplemented from time to time.

Appointment of Non-executive Directorsto Westpac Board

On February 28, 2023, Westpac Banking Corporation announced the appointment of Tim Burroughs and Michael Ullmer AO as independent Non-executive Directors, subject to regulatory approval. Tim’s appointment is expected to be effective on March 10, 2023 and Michael’s appointment is expected to be effective on April 3, 2023. The two new appointments replace former directors Steven Harker and Peter Marriott.

About Tim Burroughs

Mr Burroughs has more than 40 years’ experience in finance, international banking and mergers and acquisitions. Mr Burroughs was formerly Chairman of Investment Banking at Goldman Sachs Australia, where he worked for 11 years. Prior to this, Tim held senior positions at Merrill Lynch including Chairman of Mergers and Acquisitions. From 1993-1997, Tim was Principal at Centaurus Corporate Finance, a leading independent advisory firm.

About Michael Ullmer AO

Mr Ullmer has more than 40 years’ experience in international banking, finance and professional services. Mr Ullmer is the Chairman of Lendlease Corporation and was formerly a Non-executive Director of Woolworths Limited. Mr Ullmer was previously the Deputy Group Chief Executive Officer of the National Australia Bank (NAB) from 2007 to 2011. He joined NAB in 2004 as Finance Director and held a number of key positions including Chairman of the subsidiaries Great Western Bank (US) and JB Were. Prior to NAB, Mr Ullmer was at Commonwealth Bank of Australia initially as Group Chief Financial Officer and then Group Executive with responsibility for Institutional and Business Banking. Before that, he was a Partner at accounting firms KPMG (1982 to 1992) and Coopers & Lybrand (1992 to 1997).

Index to Exhibits

Disclosure regarding forward-looking statements

The information contained in this Report on Form 6-K contains statements that constitute “forward-looking statements” within the meaning of section 21E of the U.S. Securities Exchange Act of 1934.

Forward-looking statements are statements about matters that are not historical facts. Forward-looking statements appear in a number of places in this Report and include statements regarding our intent, belief or current expectations with respect to our business and operations, macro and micro economic and market conditions, results of operations and financial condition, capital adequacy and risk management, including, without limitation, future loan loss provisions and financial support to certain borrowers, forecasted economic indicators and performance metric outcomes, indicative drivers, climate- and other sustainability-related statements, commitments, targets, projections and metrics, and other estimated and proxy data.

We use words such as ‘will’, ‘may’, ‘expect’, ‘intend’, ‘seek’, ‘would’, ‘should’, ‘could’, ‘continue’, ‘plan’, ‘estimate’, ‘anticipate’, ‘believe’, ‘probability’, ‘indicative’, ‘risk’, ‘aim’, ‘outlook’, ‘forecast’, ‘f’cast’, ‘f’, ‘assumption’, ‘projection’, ‘target’, ‘goal’, ‘guidance’, ‘ambition’, or other similar words to identify forward-looking statements, or otherwise identify forward-looking statements. These forward-looking statements reflect our current views on future events and are subject to change, certain known and unknown risks, uncertainties and assumptions and other factors which are, in many instances, beyond our control (and the control of our officers, employees, agents and advisors), and have been made based on management’s expectations or beliefs concerning future developments and their potential effect upon us. Forward-looking statements may also be made, verbally or in writing, by members of Westpac’s management or Board in connection with this Report. Such statements are subject to the same limitations, uncertainties, assumptions and disclaimers set out in this Report.

There can be no assurance that future developments or performance will align with our expectations or that the effect of future developments on us will be those anticipated. Actual results could differ materially from those we expect or which are expressed or implied in forward-looking statements, depending on various factors including, but not limited to, those described in the section titled ‘Risk factors’ under the section ‘Risk and risk management’ in Westpac’s 2022 Annual Report on Form 20-F filed with the U.S. Securities and Exchange Commission. When relying on forward-looking statements to make decisions with respect to us, investors and others should carefully consider such factors and other uncertainties and events.

Except as required by law, we assume no obligation to revise or update any forward-looking statements contained in this Report, whether from new information, future events, conditions or otherwise, after the date of this Report.

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, thereunto duly authorized.

Exhibit 1