EU Court Brings Clarity on Cross-Border Social Security
For years, companies and employees have wrestled with one question: how do you decide which country’s social security system applies when someone works in more than one EU state?
In September 2025, the Court of Justice answered that question in the Hakamp case (C-203/24). The message was simple: when you are applying the 25% test under EU Regulation 987/2009, the only things that count are working time and pay.
What happened in Hakamp?
A Dutch resident worked for a Liechtenstein employer on a ship that operated across the Netherlands, Belgium and Germany. Dutch authorities argued that “other circumstances” should be taken into account when deciding if at least 25% of the work was done in the Netherlands. The Court rejected that approach.
The judgment makes it crystal clear:
- ≥25% of time or pay in your home country → insured there.
- <25% → insured where the employer is based.
That’s it. No extra factors like where the company is registered or where equipment is located.
Why this matters
For employers, this means less guesswork and fewer disputes. You can rely on objective numbers instead of subjective interpretations. For employees, it means certainty about which system they’re covered under.
How this links with telework
This decision sits alongside the Framework Agreement on cross-border telework, in force since July 2023. That agreement lets employees work up to 49.9% from their country of residence and still stay covered in the employer’s state, provided an A1 certificate is applied for under Article 16. So, the baseline 25% test still applies, but there’s flexibility if the telework agreement is used.
What employers should do
- Track working time and pay by country.
- Keep records up to date.
- Use the telework agreement if it applies to your situation.
- Revisit old cases if national authorities relied on “other circumstances” instead of time/pay.
The takeaway
With Hakamp, the Court has finally put an end to inconsistent approaches. For social security coverage, it all comes down to two objective numbers: either the share of working time or the share of remuneration earned in each country. In practice, most employers track working time, but pay can also be used where it provides a clearer measure.