The Convention on Mutual Administrative Assistance in Tax Matters is a convention to facilitate the entering into bilateral tax information exchange agreements between state parties.

The Convention was developed by the OECD and the Council of Europe and was open for signature to members of both organizations on 25 January 1988, and entered into force in 1995.

An amending protocol was concluded on 27 May 2010, which since coming into force became open to any state at the invitation of present state parties.

The Convention as well as the amending protocol entered into force upon the ratification of five members.

As of January 2025, one state (the United States) is a party to the original convention only, 26 states have ratified the original 1995 convention and the amending protocol, while 70 others are parties to the amended convention.