<div id="readability-page-1"><div>RNS Number : 6526L Bank of Montreal 15 December 2025 Please have this filed under the headline &#34;Publication of Prospectus&#34;Regulatory AnnouncementBank of MontrealDecember 15, 2025Not for release, publication or distribution, directly or indirectly, in or into the United States.The following supplement has been approved by the Financial Conduct Authority and is available for viewing:1st Supplement dated December 15, 2025 relating to the Programme for the U.S.$50,000,000,000 Global Registered Covered Bond Program of Bank of Montreal, unconditionally and irrevocably guaranteed as to payments of interest and principal by BMO Covered Bond Guarantor Limited Partnership.The 1st Supplement and the documents incorporated by reference therein have been submitted to the National Storage Mechanism and will shortly be available for inspection at: https://data.fca.org.uk/#/nsm/nationalstoragemechanism.DISCLAIMER - INTENDED ADDRESSEESPlease note that the information contained in the Prospectus dated September 10, 2025, as supplemented by the 1st Supplement dated December 15, 2025 (together, the &#34;Prospectus&#34;), may be addressed to and/or targeted at persons who are residents of particular countries (specified in the Prospectus) only and is not intended for use and should not be relied upon by any person outside these countries and/or to whom the offer contained in the Prospectus is not addressed. Prior to relying on the information contained in the Prospectus you must ascertain from the Prospectus whether or not you are part of the intended addressees of the information contained therein.The Covered Bonds have not been and will not be registered under the United States Securities Act of 1933, as amended (the &#34;Securities Act&#34;) or the securities laws of any state of the United States and are subject to United States tax law requirements. Subject to certain exceptions, the Covered Bonds may not be offered, sold or delivered, directly or indirectly, in the United States or to or for the account or benefit of a &#34;U.S. person&#34; (as defined in Regulation S under the Securities Act). No public offering of the Covered Bonds is being made in the United States. This announcement does not constitute an offer to sell or a solicitation to buy securities in the United States or in any other jurisdiction where such offer or solicitation would be unlawful.Your right to access this service is conditional upon complying with the above requirement.To view the full document, please paste the following URLs into the address bar of your browser:1st Supplement dated December 15, 2025http://www.rns-pdf.londonstockexchange.com/rns/6526L_1-2025-12-15.pdfDocuments Incorporated by Reference2025 Annual Information Form dated December 4, 2025http://www.rns-pdf.londonstockexchange.com/rns/6526L_2-2025-12-15.pdf2025 Annual Reporthttp://www.rns-pdf.londonstockexchange.com/rns/6526L_3-2025-12-15.pdfFor further information, please contact:Madeline MannCorporate Secretary's Dept.Phone: (647) 268-6463Email: madeline.mann@bmo.comENDThis information is provided by RNS, the news service of the London Stock Exchange. RNS is approved by the Financial Conduct Authority to act as a Primary Information Provider in the United Kingdom. Terms and conditions relating to the use and distribution of this information may apply. For further information, please contact rns@lseg.com or visit www.rns.com.RNS may use your IP address to confirm compliance with the terms and conditions, to analyse how you engage with the information contained in this communication, and to share such analysis on an anonymised basis with others as part of our commercial services. For further information about how RNS and the London Stock Exchange use the personal data you provide us, please see our Privacy Policy. END PDIFFFFWIEISELE</div></div>

Bank of Montreal has published a prospectus supplement for its $50 billion Global Registered Covered Bond Program, approved by the Financial Conduct Authority. The supplement, dated December 15, 2025, is available for viewing and is targeted at specific countries. The bonds are not registered under U.S. securities laws and are not offered in the U.S. For more information, contact Madeline Mann at madeline.mann@bmo.com.

REG - Bank of Montreal - Publication of a Prospectus