If both the U.S. and Uruguayan social security systems cover a worker’s employment
or self-employment, the agreement provides that beginning November 1, 2018, only one
country’s system covers the worker’s employment or self-employment. The agreement
does not affect a worker’s coverage prior to that date. If a worker had dually covered
earnings before November 1, 2018, those earlier earnings remain subject to social
security taxes in both countries.