Share with your friends

United States – Social Security Agreements Enter into Force in 2018, 2019

US – SSA Enter into Force in 2018, 2019

This report covers the current status of various social security agreements between the U.S. and Brazil, Uruguay, Slovenia, and Iceland.


Related content


In late 2018 and early 2019, there will be an unusual amount of activity with respect to U.S. Social Security Totalization Agreements (SSTAs), with three agreements entering into force over the space of three months.  As previously reported in GMS Flash Alert1, the SSTA with Brazil entered into force on October 1, 2018, and the SSTA with Uruguay entered into force on November 1, 2018.  

An agreement with Slovenia will enter into force on February 1, 2019.2 

In addition, a SSTA with Iceland has gone through the process to be approved by the U.S. government; however, it still requires approval from the Icelandic government in order to enter into force.   


One of the primary purposes of a SSTA is to prevent double taxation of social security taxes on workers on international assignments, which may help reduce the cost of international assignments.  Where a worker is assigned temporarily to a host country, her home country retains exclusive right to impose social security tax. 

SSTAs also provide for the coordination of social security benefits between the two countries, meaning that those who work temporarily in the host country are now more likely to accrue a benefit for the tax they pay to that country than they would be if there were no SSTA.

Once an agreement enters into force, the employer of a U.S. assignee to the host country can obtain a Certificate of Coverage (CoC) online at the Social Security Administration (SSA) website3 prior to the commencement of the assignment.  The CoC serves as proof that the employee and employer are exempt from the payment of Social Security taxes to the host country.  The U.S. Social Security Administration website4 also contains information regarding how to obtain a CoC from the other country, in the case of a worker who is assigned temporarily to the United States.

Notable Provisions Included in SSTAs

SSTAs between the United States and Brazil, Uruguay, Slovenia, and Iceland each has a provision which provides that an employee who is sent by his home country employer to a third country, who is then sent by that third country to the country that is party to the agreement, will be eligible for a CoC, if he was subject to FICA in the third country. 

Most SSTAs do not address whether a CoC can be extended beyond five years, but in practice most countries will permit extensions, under various circumstances.  However, the U.S.-Brazil SSTA includes an unusual provision which appears to prohibit extensions beyond five years, unless the person returns to the home country for at least six months.

Also included in the Brazil and the Iceland SSTAs is a provision for self-employment that provides that a person on an assignment will only be taxed in the country in which he resides.  However, the self-employment provisions of the SSTAs with Slovenia and Uruguay provide that a person temporarily residing in one country can stay covered in his home country for up to five years.


The online CoC application for Brazil became available on the U.S. Social Security website on October 1, 2018, the day that the agreement with Brazil entered into force.5  

On November 1, 2018, the Uruguay SSTA entered into force, but at the time of this publication the online application for that country is not yet available.  

Officials in the Office of International Programs have expressed a preference for online applications over submission by other methods; the specific information required for a Uruguay CoC has not yet been made known.  Thus, for the time being it is recommended that employers wait for the online application to appear on the SSA website before submitting an application for Uruguay. 


1  See the following issues of GMS Flash Alert2018-131 (October 8, 2018) and 2018-109 (August 22, 2018).

2  For prior coverage, see GMS Flash Alert 2017-042, March 3, 2017.

3  The online Certificate of Coverage application can be accessed at

4  See the SSA’s description of the SSTA for the country in question for instructions on where to address a CoC application in the other country. 

5  For prior coverage, see GMS Flash Alert 2018-131, October 8, 2018.

The above information is not intended to be "written advice concerning one or more Federal tax matters" subject to the requirements of section 10.37(a)(2) of Treasury Department Circular 230 as the content of this document is issued for general informational purposes only.


The information contained in this newsletter was submitted by the KPMG International member firm in United States.

© 2021 KPMG LLP, a Delaware limited liability partnership and a member firm of the KPMG global organization of independent member firms affiliated with KPMG International Limited, a private English company limited by guarantee. All rights reserved.

For more detail about the structure of the KPMG global organization please visit

Flash Alert is an Global Mobility Services publication of KPMG LLPs Washington National Tax practice. The KPMG logo and name are trademarks of KPMG International. KPMG International is a Swiss cooperative that serves as a coordinating entity for a network of independent member firms. KPMG International provides no audit or other client services. Such services are provided solely by member firms in their respective geographic areas. KPMG International and its member firms are legally distinct and separate entities. They are not and nothing contained herein shall be construed to place these entities in the relationship of parents, subsidiaries, agents, partners, or joint venturers. No member firm has any authority (actual, apparent, implied or otherwise) to obligate or bind KPMG International or any member firm in any manner whatsoever. The information contained in herein is of a general nature and is not intended to address the circumstances of any particular individual or entity. Although we endeavor to provide accurate and timely information, there can be no guarantee that such information is accurate as of the date it is received or that it will continue to be accurate in the future. No one should act on such information without appropriate professional advice after a thorough examination of the particular situation.

Connect with us


Want to do business with KPMG?


loading image Request for proposal

Stay up to date with what matters to you

Gain access to personalized content based on your interests by signing up today

Sign up today