In basic insurance, changing insurer is a right, not a favour. It is exercised within a deadline, and it is lost on the day that deadline passes.
The ordinary deadline: three months, for the end of a half-year
The law allows you to change insurer for the end of a half of a calendar year, with three months' notice. In practice, the termination must be in the insurer's hands by 30 November at the latest for a change on 31 December.
What counts is receipt, not the date of posting. A registered letter, sent a few days early, is the only way to have proof of it.
The letter itself need not be long, but it must be unambiguous: your surname, first name and date of birth, your insured person's number, the date on which the termination is to take effect, and the list of people concerned where the contract covers the whole family. Cancelling for yourself while believing you have cancelled for the whole household is the commonest mistake, and after 30 November it cannot be undone.
When the premium changes, a second right opens
The insurer must inform every insured person of the new premiums approved by the Federal Office of Public Health at least two months in advance. On receiving that new premium, the insured person may change insurer for the end of the month preceding the start of its validity, with one month's notice.
It is this right that makes autumn the switching season: the letter announcing next year's premium arrives, and the one-month deadline runs from there. As these lines are written, next year's premiums have not yet been published; it is your insurer's letter that will give the signal.
What can block the change
Arrears, first. An insured person in arrears may not change insurer as long as their outstanding premiums, cost-sharing, default interest and debt-collection costs are not paid in full. The balance is settled before the termination, not after.
Continuity, second. Membership of the old insurer ends only once the new insurer has told it that the person is insured without any interruption of cover. A gap is therefore legally impossible — and if the old insurer delays the departure without reason, the law makes it liable for the resulting damage.
No insurer may turn you down
This is the most important difference from a complementary policy, and it fits in one sentence from the FOPH: insurers must, within their area of activity, accept every person required to be insured. No health questionnaire, no reserve, no refusal; only the price differs from one insurer to another.
A complementary policy, by contrast, falls under the VVG/LCA: there the insurer may ask health questions, attach a reserve to the contract or refuse the application. Cancelling your complementary cover before you have written confirmation of a new contract is, for that reason, a gamble; changing basic insurer is not.
Arriving in Switzerland, or a birth: a different deadline
Everyone resident in Switzerland must take out insurance, or be insured by their legal representative, within three months of taking up residence or of birth. Joining within that period takes effect from the birth or from the day residence was taken up: cover is therefore retroactive, and care given in between is paid for.
After that deadline, the insurance only takes effect when the person joins, and a premium supplement may be added where the delay is not excusable. It is one of the few places in the system where waiting costs money directly.
What to do, in order
- Compare premiums for your commune, your age, and your current deductible and model: the FOPH publishes the official tool.
- Choose the new insurer first, and apply before you cancel.
- Send the termination by registered post, so that it arrives before 30 November.
- Check the balance: unpaid arrears cancel the change.
- Leave the complementary policy out of it: its deadlines and conditions are different.
These rules are federal. They depend neither on your canton, nor on your insurer, nor on your state of health.