A1 certificate: what the A1 form proves and when you need it

What the A1 form does in practice

The employer requests the PD A1 from the social security institution in the worker's home country and also informs the host country's authorities, according to the EU's Your Europe portal. During the posting the worker stays covered by the home system and does not build host-country pension or unemployment rights.

In German the form is often called the A1-Bescheinigung, which is why searches for "A1 Formular" lead to the same document.

How long an A1 lasts

A posting can last as long as needed to finish a specific task. If it runs past two years, the worker either moves into the host country's system or the employer applies to extend the A1's validity. The extension is granted only if the authorities of both countries agree and it is in the worker's interest (Your Europe, checked October 18, 2026).

What the A1 saves: an example

A German employer sends an employee earning EUR 35,000 to Spain for 12 months.

• With an A1: the employer keeps paying German employer contributions of 21.30%, or EUR 7,455 for the year, before the U1/U2 levies and accident insurance.
• Without one, the Spanish authorities may treat the work as covered by Spanish law, where an office employee's employer rate is 32.15%, or EUR 11,252.50. If both countries collect, the employer pays EUR 18,707.50.

Rates come from our Germany and Spain country pages, which also show the contribution caps. The employer cost index compares every country we cover.

Outside the EU: certificates of coverage

The A1 belongs to the EU coordination system only. A country such as Armenia is outside it, so coverage depends on whether a separate social security agreement exists. For US employers, the equivalent is a certificate of coverage under a totalization agreement. The US has agreements with 31 countries, and the detached-worker rule generally covers assignments expected to last 5 years or less (SSA). With the certificate, the worker stays in US Social Security for the posting.

Hiring a local person through an employer of record needs no A1 at all: that person is a local employee from day one. Sending an existing employee abroad may also need a shadow payroll for income tax and can raise permanent establishment questions.