It's not optional, it has a strict deadline, and choosing the right deductible can save you hundreds of francs a year.
You have 3 months from your arrival to take out basic health insurance (LAMal/KVG). It's a legal requirement for all residents, and coverage applies retroactively to your arrival date even if you sign up later.
Unlike Spain, there's no tax-funded public healthcare system: every resident contracts their own basic insurance with a private insurer (CSS, Helsana, Swica, Groupe Mutuel, Sanitas, Concordia, among others). All of them are legally required to offer the same minimum coverage at a price regulated by age, canton, and chosen deductible — they cannot reject you or charge you more based on your medical history for basic coverage.
Use priminfo.ch (the Confederation's official comparison tool) or comparis.ch. Prices vary hugely by canton — the same profile can pay double in Geneva compared to Uri.
Many cantons offer premium subsidies for low or moderate incomes — you need to apply directly to the cantonal administration, it's not automatic.
Covers extras like a private hospital room, alternative medicine, dental, or glasses. It's not mandatory, and unlike basic coverage, it does involve a health questionnaire.