A Social Security Totalization Agreement applies in situations where a worker from one country works in the other country and is covered by the social security systems of both countries for the same work. When "dual coverage" occurs, the worker or his or her employer may be required to pay social security contributions to the two countries simultaneously. Totalization agreements are designed to alleviate such problems.

The U.S. has totalization agreements with Canada and with 17 European countries. The first agreement (with Italy) became effective on November 1, 1978 while the latest agreement (with Hungary) became effective in 1999. The Social Security Administration maintains a page on International Agreements which, among other things, contains a description of each agreement and the text of 17 agreements (The next two agreements, both of which have been negotiated, but not yet signed, are with Chile and South Korea).

The United States has social security totalization agreements with the following countries:

Austria	Belgium	Canada	Finland
France	Germany	Greece	Ireland
Italy	Luxembourg	Netherlands	Norway
Portugal	Spain	Sweden	Switzerland
United Kingdom

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