Filed Pursuant to Rule 424(b)(3)
Registration Statement No. 333-264388
Prospectus Addendum to the Prospectus Supplement dated May 26, 2022 and
the accompanying Prospectus dated May 26, 2022.
Senior Medium-Term Notes
Bank of Montreal or any of its affiliates, including BMO Capital Markets Corp., may use this prospectus addendum, the accompanying prospectus
supplement dated May 26, 2022 relating to Senior Medium-Term Notes, Series H and Senior Medium-Term Notes, Series I, and the accompanying prospectus dated May 26, 2022 in connection with market-making transactions of notes that were
originally issued under a similar prospectus supplement for Senior Medium-Term Notes with a date earlier than May 26, 2022, and a similar prospectus, with a date earlier than May 26, 2022. We refer below to such earlier prospectus
supplement as the “earlier prospectus supplement” and such earlier prospectus as the “earlier prospectus”.
When this
prospectus addendum, the accompanying prospectus supplement dated May 26, 2022 relating to Senior Medium-Term Notes, Series H and Senior Medium-Term Notes, Series I, and the accompanying prospectus dated May 26, 2022 are used in connection
with a market-making transaction, you should note that the accompanying prospectus supplement dated May 26, 2022 relating to Senior Medium-Term Notes, Series H and Senior Medium-Term Notes, Series I, supersedes the earlier prospectus
supplement, and the accompanying prospectus dated May 26, 2022 supersedes the earlier prospectus. When you read the prospectus supplement or pricing supplement with the specific terms of the offered notes, please note that all references in it
to the earlier prospectus supplement should instead refer to the accompanying prospectus supplement dated May 26, 2022 relating to Senior Medium-Term Notes, Series H and Senior Medium-Term Notes, Series I, and all references in it to the
earlier prospectus should instead refer to the accompanying prospectus dated May 26, 2022.
You should read the terms of the
accompanying prospectus supplement or pricing supplement, which describes the specific terms of the offered notes, together with the accompanying prospectus supplement dated May 26, 2022 relating to Senior Medium-Term Notes, Series H and Senior
Medium-Term Notes, Series I, and the accompanying prospectus dated May 26, 2022.
The offered notes are our unsecured obligations and
are not savings accounts or deposits that are insured by the United States Federal Deposit Insurance Corporation, the Deposit Insurance Fund, the Canada Deposit Insurance Corporation or any other governmental agency or instrumentality or other
entity.
Prospectus Addendum dated May 26, 2022