← Blog4 March 20225 min readEditorial teamDEUAENRU
For businesses
A1 certificate for posted workers: why clients in Germany should check it
When a contractor from another EU country sends workers to your site, they stay insured in their home country. The proof is the A1 certificate (A1-Bescheinigung). For you as the client it is more than a form: it protects you from back payments and trouble during inspections.
What the A1 certificate proves
The A1 certificate is issued by the social security institution in the employer’s country – in Poland, for example, ZUS. It confirms that the worker remains covered by his home country’s social security rules while working in Germany. The legal basis is EU Regulation 883/2004. A posting is generally possible for up to 24 months.
A valid A1 certificate is in principle binding on German authorities. As long as it exists, no German social security contributions are due for that worker.
Why you should care as a client
Inspections by the customs unit for undeclared work (FKS) take place directly on the building site, in the hotel or in the field. If there is no A1 certificate, the authorities check whether German social insurance applies. That costs time, can stop the job and in the worst case leads to back payments.
In certain cases you are liable yourself:
- Minimum wage: a business that commissions another business with work or services may be liable for the minimum wage of the subcontractor’s staff (section 13 MiLoG).
- Construction: in the construction industry, the main contractor may be liable for its subcontractors’ social security contributions (section 28e(3a) SGB IV).
Documents to ask for
- an A1 certificate for every worker – or proof that it was applied for before the job started;
- the customs notification via the minimum wage reporting portal, which the foreign employer must file before work starts;
- clearance certificates (Unbedenklichkeitsbescheinigungen) from the tax office and social security;
- trade registration or a commercial register extract of the contractor;
- the contract, making clear which result or service is owed – see Contract for work or temporary agency work?
Common mistakes
- The A1 certificate is applied for only after the team has started work.
- The place or period on the certificate does not match the actual assignment.
- Workers move between projects without the paperwork being updated.
Which documents the workers themselves need is covered in Working in Germany: which documents you need.
FAQ
Who applies for the A1 certificate?
The employer in the home country, at the local social security institution – not the client in Germany.
How long is an A1 certificate valid?
For the period of the posting applied for, usually no more than 24 months.
Does the A1 certificate have to be on site?
It should be available quickly during inspections. The easiest way is a copy held by the foreman on site.
Does the A1 certificate also apply to non-EU citizens?
Yes, if they are regularly employed and insured by an employer in the EU. To enter Germany they also need the right residence papers.
