Your first ninety days in Switzerland, dated.

In short: Switzerland gives every new resident three months from taking up residence — the date you register with your local residents’ office, not the day you land — to take out the compulsory KVG basic insurance. Enrol inside the window and cover backdates to that date, with premiums owed from it too. Miss it and the backdating vanishes: the canton can assign you an insurer, a surcharge of 30 to 50 per cent runs for twice the delay up to five years, and the intervening months were genuinely uninsured.

Switzerland hands every new arrival the same clean deal, and most people misread one clause of it. You have three months from taking up residence to take out the compulsory basic insurance — the KVG cover every resident must hold — and if you do it inside the window, cover applies retroactively to the day residence began. Insure in week eleven and you were, legally, covered since week one. It is the most generous arrival rule on this site, and it has a cliff edge: miss the window and the retroactivity vanishes — replaced by a quantified premium surcharge and a genuine uninsured gap. Backdating is the reward for punctuality, not a safety net for its absence.

One correction before the calendar, because we had it loose. The day the three months run from is not the day you land. KVG Art. 5 para 1 and KVV Art. 7 para 1 tie cover to the day you take up residence, which in practice is the date on your registration confirmation from the residents’ office. Arrive in July, register in September, and you have been reading the wrong date all summer. Everything below is dated from the right one.

Here is the ninety days, dated.

Before you land: the shape of the system, in three facts

Arrivals lose time in weeks one and two re-learning things the system could have told them in a paragraph, so here is the paragraph.

Premiums are per person, not per household. Each member of the family holds their own policy and pays their own premium, children included. A quoted figure for one adult tells you close to nothing about what a family of four will pay, and budgeting the household as a single line is the most common financial shock of a Swiss arrival.

Premiums ignore your income and your medical history entirely. They vary by age, by insurer, and by premium region — a federal designation, so your street address matters, not only your canton. Two people on the same salary pay different premiums because of their birth year and their postcode; two people on wildly different salaries in the same building pay the same. Very few systems in the world price this way, and almost nobody arrives expecting it.

Nothing you already hold substitutes for it unless you fit a narrow, formally granted exemption. Which is the first errand.

Weeks 1–2: settle the two facts that shape everything

Are you exempt? A defined minority is: temporary students with equivalent cover, cross-border commuters and pensioners insured in their country of residence, diplomatic staff, EU/EFTA workers and pensioners, and posted workers whose home social security continues to cover them on a limited assignment. Exemption is applied for, through the cantonal authority, inside the same three months — not assumed, and not granted by producing a policy you like the look of. If you think you qualify, that application is your first errand, because everything else depends on the answer and because the worst available outcome is paying Swiss premiums you never owed.

Do you work eight hours a week for one employer? Here we had the mechanism backwards, and the correction changes which way you should worry. Accident cover is included in compulsory Swiss cover by default. What the eight-hour threshold gives you is the right to ask your insurer to suspend it while the employer’s accident policy carries the risk (KVG Art. 8 para 1; UVV Art. 13). Under eight hours, or not employed, you leave it in place and do nothing. One payslip fact, one request, real money — and one line for later that matters more than the saving: the suspension does not lapse when the job does. If the hours drop or the employment ends, the switch has to be flicked back by you, in writing, or the hole opens with nobody’s system flagging it.

Weeks 3–6: choose, knowing what cannot differ

Every insurer must accept you for the basic package within the area it operates in — no fund inside its own territory may refuse you, regardless of age or health (KVAG Art. 5 lit. i) — and the compulsory benefits are identical everywhere by law. So the choosing is narrower than the market makes it look: you are picking a premium, a service standard, and a model (standard, family-doctor, telemedicine, HMO — the restricted models trade choice for discount). What you are not picking is coverage.

Two practical consequences. First, premiums for that identical cover differ substantially between funds, which means the comparison is a price-and- service exercise, not a benefits exercise — and service is not a soft factor here: processing speed and the language your claims are handled in are what you will actually experience. Second, any comparison site that implies fund A “covers more” than fund B in the basic package is describing supplementary products, which are a separate decision with opposite rules — there, insurers may refuse and may underwrite. That reversal is the single most important thing to understand in your first month: basic cover cannot say no to you, ever; supplementary cover can, and its answer depends on the health you have on the day you apply. Which is why supplementary applications belong early, while you are healthy, or not at all.

Weeks 6–10: the franchise decision, made with arithmetic

The annual franchise — your deductible — is not a sliding scale but a set of fixed rungs (KVV Arts. 93, 103). For adults: CHF 300 as the ordinary level, then 500, 1,000, 1,500, 2,000 and 2,500. For children: none at all by default, with optional levels of 100, 200, 300, 400, 500 and 600 — the half of the system almost no English-language summary mentions. No insurer is obliged to offer every rung. The premium falls as the franchise rises, and the honest way to choose is arithmetic, not optimism: at the top rung you are trading roughly two thousand francs of extra exposure for the premium saving, and the franchise is not the end of your own contribution. Above it you still pay a 10% retention, capped at 700 francs a year for adults and 350 for children, and a daily hospital contribution of 15 francs for inpatient stays, which sits outside that cap and which children and young adults in education do not pay at all. So the worst realistic year at the top rung is roughly 2,500 plus 700 plus your hospital days; at the bottom, roughly 300 plus 700 plus the same days. Healthy and liquid, the high franchise usually wins; expecting a baby or managing a condition, the low one does. Decide from your likely year, not your hoped one — and remember the per-person rule applies here as well, so a family is choosing four franchises and carrying the sum of four exposures.

Can you keep the international policy you already have?

Usually not, and this is worth settling early rather than discovering in month four. Compulsory cover has to be a recognised Swiss product; an international plan does not substitute for it unless one of the exemption doors above actually applies to you.

That leaves a narrower and more useful question: is the international policy worth keeping alongside the Swiss one, for travel, for a home country you return to often, for cover that follows a later transfer? Here one piece of context helps, because arrivals routinely assume Switzerland is the most expensive place on earth for anything medical. In the SIP Health Cost Index 2025 — fifty countries, comparable international cover — Switzerland sits 15th of 50, at about $8,912 a year: mid-table, not the outlier its reputation suggests. The same index shows why the timing of that decision matters more than the level: the 24-year-old profile runs about $6,392, the 35-year-old about $8,017, and the 50-year-old about $12,328 — a multiple of 1.54 across those fifteen years. If an international layer is going to be part of your life, the year to arrange it is the year you are youngest, which is this one.

Weeks 10–13: sign, and mind the two calendars

Take out the policy before day ninety and the clock forgives everything — cover backdates, premiums are owed from the residence date, no gap ever existed. What arrives in the post afterwards surprises people: a policy certificate naming your franchise, model and whether accident cover is suspended, and an invoice covering the backdated months in one lump. Read the certificate against what you thought you chose; that document, not the sales conversation, is your contract.

Two administrative notes for the same fortnight. Your commune may write to you about insurance proof — cantons follow up on new arrivals, and non-responders can eventually be assigned to a fund, a fallback you do not want, because somebody else then picks your insurer. And if you hold travel or international cover from home, keep it running until the Swiss policy is signed — not because the law needs it, but because life does not respect legal retroactivity’s paperwork lag.

One date to confirm rather than assume, today: the day the canton considers your residence to have started. That is the day the three months run from, and the day cover backdates to — and it is not the day you landed or the day you signed the lease. It is on your registration confirmation from the commune, and it is worth reading off the document rather than reconstructing from memory. If a partner or child follows you later, they take up residence on their own date and enrol on their own clock — your September enrolment does not cover the person who registers in November.

What actually happens if you miss day ninety

It is worth being concrete, because the vagueness is what lets people drift — and worth being accurate, because we were not. Three consequences arrive together. The canton can assign you an insurer (KVG Art. 6 para 2). A surcharge of 30 to 50 per cent of the premium is levied for twice the length of the delay, capped at five years (KVV Art. 8) — and where the late enrolment is a child’s, the parents owe it. And the backdating does not apply: cover starts at signature, so the intervening months were not merely unbilled, they were uninsured. If something happened in them, it happened to an uninsured person.

What is not a consequence: losing the choice of franchise and model. An earlier version of this article said late joiners forfeit it. No such rule exists in the KVG or the KVV, and we have withdrawn the claim rather than quietly deleting it. The rule that genuinely constrains anyone joining part-way through a year — the punctual included — is KVV Art. 94: moving to a higher franchise only takes effect from the following January.

The reassurance, such as it is: you cannot be refused basic cover by an insurer operating where you live. Late, assigned and surcharged is a bad outcome and a recoverable one. There is no version of this where Switzerland leaves you without basic cover — only versions where it costs more and you chose less of it.

The mistakes, ranked by cost

Missing day ninety is the expensive one: surcharge plus gap, both avoidable. Leaving accident cover suspended after the job that justified the suspension has ended is the quiet one. Budgeting per household instead of per person is the one that ruins the first year’s finances rather than the first year’s cover. Skipping the supplementary question until after a diagnosis is the irreversible one — basic insurance can never refuse you; supplementary can, and does, and remembers. And treating the franchise as a personality test rather than a sum is the perennial one.

Switzerland is our home market — the deep versions of every decision here, fund comparisons included, live on expat-savvy.ch. The arrival-shaped summary, with the verified rule and the traps, is on our Switzerland page.