UNITED STATES SECURITIES AND EXCHANGE COMMISSION

1 UNITED STATESSECURITIES AND EXCHANGE COMMISSIONW ashington, 20549 FORM 20-FCommission File Number: 1-10167 WESTPAC BANKING CORPORATIONA ustralian Business Number 33 007 457 141(Exact name of Registrant as specified in its charter)New South Wales, Australia(Jurisdiction of incorporation or organization)275 Kent Street, Sydney, NSW 2000, Australia(Address of principal executive offices)Westpac Banking Corporation, New York branch, 575 Fifth Avenue, 39 Floor, New York, New York 10017-2422,Attention: Branch Manager, telephone number: (212) 551-1800(Name, Telephone, E-mail and/or Facsimile number and Address of Company Contact Person) SECURITIES registered or to be registered pursuant to Section 12(b) of the Act: SECURITIES registered or to be registered pursuant to Section 12(g) of the Act: NoneSecurities for which there is a reporting obligation pursuant to Section 15(d) of the Act.

2 Notes due November 23, 2018, Floating Rate Notes due November 23, 2018, Notes due January 17, 2019, Floating Rate Notes due January 17, 2019, Notes due May 13, 2019, Floating Rate Notes due May 13, 2019, Notes due August 19, 2019, Floating Rate Notes due August 19, 2019, Notes due November 19, 2019, Notes due March 6, 2020, Floating Rate Notes due March 6, 2020, Notes due May 15, 2020, Floating Rate Notes due May 15, 2020, Notes due May 26, 2020, Notes due November 23, 2020, Notes due January 25, 2021, Floating Rate Notes due January 25, 2021, Notes due May 13, 2021, Floating Rate Notes due May 13, 2021, Notes due August 19, 2021, Floating Rate Notes due August 19, 2021, Notes due January 11, 2022, Floating Rate Notes due January 11, 2022, Notes due June 28, 2022, Floating Rate Notes due June 28, 2022, Notes due January 11, 2023, Floating Rate Notes due January 11, 2023, Notes due May 15, 2023, Floating Rate Notes due May 15, 2023, Notes due May 13, 2026, Notes due August 19, 2026, Notes due March 8, 2027, Notes due January 25, 2028, Subordinated Notes due November 23, 2031, Fixed Rate Resetting Perpetual Subordinated Contingent Convertible SECURITIES and notes issued under our Retail Medium-Term Notes program (Registration Statement No.)

3 333-172579)Indicate the number of outstanding shares of each of the issuer s classes of capital or common stock as of the close of the period covered by the annual by check mark if the registrant is a well-known seasoned issuer, as defined in Rule 405 of the SECURITIES _ No If this report is an annual or transition report, indicate by check mark if the registrant is not required to file reports pursuant to Section 13 or 15(d) of the SECURITIES EXCHANGE Act of No _Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the SECURITIES EXCHANGE Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 _ No Indicate by check mark whether the registrant has submitted electronically every Interactive Data File required to be submitted pursuant to Rule 405 of Regulation S-T during the preceding 12 months (or for such shorter period that the registrant was required to submit such files).

4 Yes _ No (not currently applicable to registrant)Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, or an emerging growth company. See the definitions of large accelerated filer, accelerated filer, and emerging growth company in Rule 12b-2 of the EXCHANGE an emerging growth company that prepares its financial statements in accordance with GAAP, 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. The term new or revised financial accounting standard refers to any update issued by the Financial Accounting Standards Board to its Accounting Standards Codification after April 5, by check mark which basis of accounting the registrant has used to prepare the financial statements included in this GAAP International Financial Reporting Standards as issued by the International Accounting Standards Board _Other If this is an annual report, indicate by check mark whether the registrant is a shell No _ REGISTRATION STATEMENT PURSUANT TO SECTION 12(b) OR (g) OF THE SECURITIES EXCHANGE ACT OF 1934Or_ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the fiscal year ended September 30, 2018Or TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d)

5 OF THE SECURITIES EXCHANGE ACT OF 1934Or SHELL COMPANY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Title of each className of each EXCHANGE on which registeredOrdinary sharesListed on the New York Stock EXCHANGE , not for trading, but only in connection with the registration of related American Depositary Shares, pursuant to the requirements of the New York Stock Depositary Shares, each representing the right to receive one ordinary shareNew York Stock ExchangeOrdinary shares3,434,796,711 fully paidLarge accelerated filer _Accelerated filer Non-accelerated filer Emerging growth company thTable of contentsAnnual ReportForm 20-F cross-reference index2 Guide 3 cross-reference index4 Section 15 Information on Westpac6 Business strategy6 Outlook9 Significant developments11 Corporate governance23 Directors report46 Remuneration Report62 Section 293 Five year summary94 Reading this report95 Review of Group operations97 Income statement review99 Balance sheet review107 Capital resources111 Commitments113 Divisional performance114 Consumer Bank117 Business Bank118BT Financial Group (Australia)

6 119 Westpac Institutional Bank122 Westpac New Zealand123 Group Businesses125 Risk and risk management129 Risk factors129 Risk management142 Credit risk142 Liquidity risk143In this Annual Report a reference to Westpac , Group , Westpac Group , we , us and our is to Westpac Banking Corporation ABN 33 007 457 141 and its subsidiaries unless it clearly means just Westpac Banking certain information about the basis of preparing the financial information in this Annual Report see Reading this report in Section 2. In addition, this Annual Report contains statements that constitute forward-looking statements within the meaning of Section 21E of the US SECURITIES EXCHANGE Act of 1934. For an explanation of forward-looking statements and the risks, uncertainties and assumptions to which they are subject, see Reading this report in Section contained in or accessible through the websites mentioned in this Annual Report does not form part of this report unless we specifically state that it is incorporated by reference and forms part of this report.

7 All references in this report to websites are inactive textual references and are for information risk144 Operational risk and compliance risk145 Other risks146 Westpac s approach to sustainability150 Sustainability performance150 Five year non-financial summary155 Other Westpac business information160 Section 3163 Financial statements164 Notes to the financial statements170 Statutory statements287 Section 4291 Shareholding information292 Additional information307 Information for shareholders311 Glossary of abbreviations and defined terms3152018 Westpac Group Annual Report1(for the purpose of filing with the UNITED STATES SECURITIES and EXCHANGE COMMISSION )Form 20-F cross-reference index20-F item number and descriptionPagePart IItem of directors, senior management and advisersNot applicableItem statistics and expected timetableNot applicableItem informationSelected financial data93, 99, 107-108, 310 Capitalisation and indebtednessNot applicableReasons for the offer and use of proceedsNot applicableRisk factors129-141 Item on WestpacHistory and development of Westpac6, 9-22 Business overview6-22 Organisational structure8, 270-272 Property, plants and equipment160 Item staff commentsNot applicableItem and financial review and prospectsOperating results97-112, 114-128 Liquidity and capital resources111-113, 143-144, 146-149 Research and development, patents and licences applicableTrend information103-111.

8 114-128 Off-balance sheet arrangements149 Tabular disclosure of contractual obligations113 Safe harbor95 Item , senior management and employeesDirectors and senior management46-55, 57-59 Compensation62-89, 281-284 Board practices25-50 Employees160 Share ownership57-59, 281-284, 292 Item shareholders and related party transactionsMajor shareholders292-300 Related party transactions161, 282-284 Interests of experts and counselNot applicableItem informationConsolidated statements and other financial information163-290 Significant changes11-20, 284 Item offer and listingOffer and listing details301 Plan of distributionNot applicableMarkets23, 311-313 Selling shareholdersNot applicableDilutionNot applicableExpenses of the issueNot applicable22018 Westpac Group Annual Report(for the purpose of filing with the UNITED STATES SECURITIES and EXCHANGE COMMISSION )

9 Form 20-F cross-reference indexPageItem informationShare capitalNot applicableMemorandum and articles of association307-309 Material contracts160 EXCHANGE controls303-304 Taxation304-306 Dividends and paying agentsNot applicableStatements by expertsNot applicableDocuments on display309 Subsidiary informationNot applicableItem and qualitative disclosures about market risk144-145, 241-243 Item of SECURITIES other than equity securitiesDebt securitiesNot applicableWarrants and rightsNot applicableOther securitiesNot applicableAmerican depositary shares302 Part IIItem , dividend arrearages and delinquenciesNot applicableItem modifications to the rights of security holders and use of proceedsNot applicableItem and procedures149, 288, 289 Item committee financial expert37 Item of ethics32-35 Item accountant fees and services37, 281 Item from the Listing Standards for audit committeesNot applicableItem of equity SECURITIES by the issuer and affiliated purchasers113, 266-268 Item in Registrant s certifying accountantNot applicableItem governance23 Item safety disclosureNot applicablePart IIIItem 17.

10 & 18. Financial statements163-290 Item income statements for the years ended 30 September 2018, 2017 and 2016164 Consolidated balance sheets as at 30 September 2018 and 2017166 Consolidated statements of comprehensive income for the years ended 30 September 2018, 2017 and 2016165 Consolidated statements of cash flows for the years ended 30 September 2018, 2017 and 2016169 Notes to the financial statements170-286 Management s report on the internal control over financial reporting288 Report of independent registered public accounting firm2892018 Westpac Group Annual Report3 Guide 3 cross-reference indexPagePart I Distribution of assets, liabilities and stockholders equity; interest rates and interest differentialAverage balance sheets107, 189-191 Analysis of net interest earnings100-101, 189-191 Volume and rate movement100, 189-191 Part II Investment portfolioBook value of investments193 Maturity profile194, 238-241 Book value and market value > 10% of shareholders193 Part III Loan portfolioTypes of loans195-198 Maturities and sensitivities of loans to changes in interest rates199 Risk elementsNon-accrual, past due and restructured loans110-111, 229-233 Potential problem loans110-111 Foreign outstandings143 Loan concentrations143 Other interest bearing assets192-194, 227-228 Part IV Summary of loan loss experienceAnalysis of the allowance for loan losses200-203 Allocation of the allowance for loan losses200-203 Part V Deposits206-207 Part VI Return on equity and assets94.