FlagSageCertificate of coverage
Glossary term
A certificate of coverage is a document issued under a social security agreement that shows which country's social security system covers a worker.
Under US totalization agreements, the IRS says a person claiming exemption from US Social Security and Medicare taxes must get a certificate of coverage from the social security agency of their home country and give it to their US employer. The IRS points to published procedures for people who cannot obtain one.
In the European Union, the portable document A1 does a similar job for workers posted to another EU country. The Your Europe portal says it proves the worker remains covered by the home country's system and is issued for a maximum of 24 months, with extensions possible if the countries involved agree. While it is valid, the host country's authorities must recognize it.
The certificate deals only with social security coverage. It does not decide income tax residence, the right to work or the right to stay in a country.
Not to be confused with
- Tax residency certificate. A tax residency certificate confirms residence for income tax treaty purposes, not social security coverage.
- Totalization agreement. The agreement sets the rules, and the certificate is the evidence used under it.
Sources
- Totalization agreementsOfficial guidance
- Social security cover when you live or work in another EU countryOfficial guidance
Related
- Countries covered
- General
- Sources
- 2 sources
- Tax year
- Current rules as checked
- Review
- Not professionally reviewed
Sources checked November 8, 2026