Starting work in Switzerland: what to do in your first 3 months

You've just signed a contract with a company in Switzerland. Congratulations — that's a big step. But between the excitement of a new job and the administrative reality, there's often a moment of confusion: where do I even start?

Here are the essential steps to take in the first three months of working in Switzerland when you live in France.

The G permit: your cross-border residence permit

It's your Swiss employer who initiates the G permit application (the cross-border worker permit) with the cantonal population office. You don't need to do the paperwork yourself, but you'll need to provide:

• A copy of your ID or passport
• Proof of address in France (less than 3 months old)
• Your signed employment contract
• A recent passport-style photo

Processing usually takes 2 to 4 weeks. Good news: you can start working as soon as the application has been filed — no need to wait for the final permit.

Health insurance: the most important choice

As a new cross-border worker, you have 3 months from your first day of work to choose your health insurance scheme. This choice is permanent: it can only be made again in specific situations, such as returning to work in Switzerland after a period of unemployment in France, changing your country of residence, or retiring. Losing your job, getting married or having a child does not reopen the choice. So take the time to understand both options.

Option 1: LAMal

This is Switzerland's mandatory health insurance. You sign up with a Swiss insurer (Helsana, CSS, Groupe Mutuel, etc.). It covers your care in Switzerland and, thanks to the S1 form (see below), your care in France at French social security rates — a top-up insurance (mutuelle) can cover the rest. Premiums don't depend on your salary: they vary by insurer and age, with a specific scale for people living in France.

Option 2: CMU (via the CPAM)

You stay in the French system. This is often simpler if you mainly receive treatment in France. Contributions are income-based: 8% of your income from two years earlier, after an allowance equal to 25% of the annual French social security ceiling.

If you don't make any choice within 3 months, you will be automatically enrolled in LAMal. Take the time to compare — the financial and practical implications can be very different depending on your family situation and healthcare habits.

The S1 form: linking Switzerland and France

If you choose LAMal, your Swiss insurer will issue an S1 form (formerly E106). This document allows you to register with the CPAM in France to also benefit from French healthcare coverage.

In practice, the S1 certifies that you are insured in Switzerland and opens your rights in France. Without this form, you won't have an active carte Vitale.

The steps:

• Request the S1 from your Swiss LAMal insurer
• Send it to your local CPAM office in France
• The CPAM registers your rights and issues your carte Vitale

Tax declaration in France

Even if your salary is paid in Switzerland and you pay (or don't pay) tax at source in Switzerland, you must declare your income in France. This is mandatory for all French tax residents.

Depending on the canton where you work, the tax regime differs:

• Cantons under the 1983 agreement (Bern, Solothurn, Basel-Stadt, Basel-Landschaft, Vaud, Valais, Neuchâtel, Jura): you are taxed in France, and you will need to provide a 2041-AS attestation to your Swiss employer, renewed every year
• Canton of Geneva: tax is withheld at source in Switzerland, but income must still be declared in France (with a tax credit)
• Other cantons (Fribourg, Zurich, Ticino…): as in Geneva, tax is withheld at source in Switzerland and income is declared in France with a tax credit

The first declaration can be confusing. Don't hesitate to get help filling in the forms correctly — a mistake or oversight can have consequences for several years.

A Swiss bank account: not required, but practical

There is no obligation to open a Swiss bank account. Many employers can pay your salary into a French account (in euros, with conversion). But a Swiss account can be useful for:

• Receiving your salary in Swiss francs without exchange fees
• Paying for everyday expenses in Switzerland (fuel, meals, parking)
• Managing the exchange rate to your advantage

Several Swiss banks offer packages for cross-border workers. If you decide to open an account, remember to declare it to the French tax authorities (form 3916, foreign accounts).

URSSAF: a yearly declaration if you choose the CMU

If you chose French health insurance (CMU), you must declare your income every year to URSSAF's service for cross-border workers in Switzerland (the declaration period is in the autumn), then pay the corresponding contribution. Each person concerned files their own declaration. If you don't declare, the contribution is calculated on a very high flat-rate basis — this is a deadline not to miss.

If you also have business activity in France (a micro-business, for example), other URSSAF contributions may apply.

Making sense of it all

There's a lot to do in a short time — and every situation is a little different. The most important thing: don't miss the 3-month deadline for health insurance, and keep a record of every document sent and received.

I'm not a tax specialist or a lawyer, but as an administrative assistant specialising in supporting cross-border workers, I can help you organise your documents, track deadlines, and make sure nothing has been overlooked.

Want to clarify your situation? Book a free initial consultation — we'll review everything together.