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People on low incomes receive support in paying their health insurance premiums. The question of who is entitled to a reduced premium is regulated at cantonal level. The main criteria are level of income and the number of children. In many cantons, you will be contacted by the local authority if you are entitled to a reduction. Your financial circumstances are checked when you file your tax return. In certain cantons, a reduction has to be applied for. This means you only become entitled if you actively request a reduction each year.
If you want to check whether you are entitled to a reduction, or if you want to apply for a reduction, contact the office concerned in your canton or commune of residence.