Guide · Customs/FKS

FKS audit process: what customs checks & how to be prepared

How an FKS audit works, which documents customs demands and how to present them instantly.

By: Sandy Smajić · Founder & compliance expert, EmployGuardReviewed by: EmployGuard Compliance-TeamLast updated: 26 June 2026

What is the FKS?

The FKS (Finanzkontrolle Schwarzarbeit) is a unit of German customs. It checks compliance with minimum wage, reporting and recording duties and fights illegal employment — especially often in construction.

How an audit runs

  • Unannounced arrival on site, interviews and identity checks.
  • Matching people found against filings and working-time records.
  • Request of documents (working time, wages, A1, exemption certificate).

Documents customs demands

  • Gap-free working-time records (start/end/breaks).
  • Proof of minimum wage and wage payments.
  • A1 certificates and residence/work permits.
  • For subcontractors: §48b exemption certificate.

Prepared with EmployGuard

All proof is stored digitally, audit-proof and centrally per site/worker. Working-time records incl. GPS location and compliance documents export in one click — ideal for instant presentation to the FKS.

FAQ

Does customs announce an FKS audit?

Usually not. Site inspections are mostly unannounced, so proof should be presentable at any time.

What fines apply for breaches?

Depending on the breach (minimum wage, recording, illegal employment) up to €30,000 or €500,000; undeclared work also carries criminal consequences.

How do I best prepare?

Keep gap-free, audit-proof time tracking, current A1/residence titles and §48b proof centrally available — instantly exportable with EmployGuard.