If this is the case, it means that a foreign social security pension paid to a person established in the United Kingdom (for the purposes of the Agreement) is taxable only in the United Kingdom. Provisions to remove double coverage for workers are similar in all U.S. agreements. Each sets a basic rule that refers to a worker`s place of employment. Under this fundamental “rule of territoriality,” an employee who would otherwise be covered by both the U.S. system and a foreign system is subject exclusively to the coverage laws of the country in which he or she works. The bilateral social security agreement with Chile started on 1 June 2015.This guide has been updated to add Chile to the list of non-EEA countries that have concluded an agreement with the United Kingdom. .