Supplementary insurance rules
Supplementary health insurance premiums (for dental, private hospital, alternative medicine, etc.) are also deductible, but under a separate category. The total deduction for all insurance premiums (basic + supplementary + accident + life) is capped at a combined canton-specific limit.
Most cantons allow a flat deduction for insurance premiums that covers basic health, accident, and personal liability insurance. Supplementary health premiums paid above that flat amount can often be claimed as additional deductions, but receipts are required.
Check whether your canton requires you to itemise supplementary premiums individually or whether a standard lump-sum deduction is available. The official FTA publication on health-cost deductibility explains the canton-by-canton breakdown.
What counts as a medical expense
Beyond premiums, you can deduct unreimbursed medical costs caused by illness, accident, disability, or pregnancy. This includes doctor visits, hospital stays, prescription medication, dental treatment, psychotherapy, and medically prescribed transport.
The deductible threshold is 5% of net income (federal), plus any canton-specific deductible. Only costs above that threshold are claimable. For example, if your net income is CHF 100'000, the first CHF 5'000 of medical expenses are not deductible.
Keep all invoices, receipts, and prescriptions. The tax authority may ask for documentation, especially for large amounts or recurring treatments. Some cantons also allow deductions for preventative health measures, so check your local rules.
How to claim on the tax return
Health insurance premiums are claimed in the 'Insurance premiums' section of your Swiss tax return. The exact field depends on your canton's form, but most tax software guides you to the correct line.
If you use the ESTV's ICTax portal or your canton's e-filing system, the premium deduction is usually pre-filled with a standard amount. Adjust it to your actual paid premiums if they exceed the standard estimate.
For expats, the key documents are: your annual premium statement from your health insurer, receipts for supplementary premiums, and a record of unreimbursed medical costs. Keep these with your tax documents in case of an audit. The Swiss tax return documents guide has a broader checklist for what to prepare.
If you are taxed at source, remember that you generally cannot claim deductions directly. You must apply for a tariff correction or submit an ordinary tax return to benefit from premium deductions above the source tax standard allowance.