The rule: 3 months to insure yourself
Anyone settling in Switzerland must take out basic LAMal insurance within 3 months of arrival (or taking up residence / starting work). It is an individual legal obligation: every family member, including children and babies, needs their own policy.
Retroactive to your arrival date
Crucial point: even if you subscribe in the 3rd month, coverage (and premiums) applies retroactively to your arrival date. You will owe the elapsed months' premiums. Insure quickly to be covered, and compare from day one to avoid overpaying.
Permits B, L, students: special cases
Permit B or L holders face the same LAMal obligation. Some posted workers or foreign students can request an exemption if they prove equivalent coverage at home — but conditions are strict and the request goes to the cantonal authority within 3 months. When in doubt, LAMal is the safe path.
Subsidies: don't forget them
Depending on income and canton, you may qualify for a premium reduction (subsidy). Thresholds and amounts vary widely between cantons (Geneva, Vaud, etc.). Apply via your cantonal compensation office. Many newcomers qualify without knowing — check your eligibility on arrival.