What Documents Do I Need for the Tax Return?

A complete and well-prepared tax return not only saves time but also helps to claim all possible deductions. Many taxpayers wonder every year: What documents do I need to submit?

In this article, you will find an overview of the most important documents you need for the tax return in Switzerland – from salary statement to insurance certificates.

Basic documents

Personal data

• Last final tax assessment
• Tax return form or login details for your canton's online platform
• Current AHV number (social security number)

Income

• Salary statement from employer (Form 11)
• Proof of secondary income, fees or self-employed activities
• Certificates for pensions or daily allowances (AHV, IV, unemployment, sick pay)
• Family compensation fund: certificate of family allowances

Assets

• Statements for all bank and postal accounts (balance as of 31 December)
• Securities lists (shares, funds, bonds) with market values as of 31 December
• Details of cryptocurrencies and digital assets (market price per Federal Tax Administration)
• Details of life insurance with surrender value
• Vehicle registration documents and value estimates
• Cash, precious metals and other tangible assets

Property and home ownership

• Tax value and imputed rental value of property (per cantonal assessment)
• Mortgage interest certificates (bank confirmations)
• Maintenance and renovation costs (receipts or flat-rate deduction – varies by canton)
• Proof of energy-efficiency renovations and heritage conservation investments
• Utility cost statements for rented properties
• Building insurance certificate

Insurance and pensions

Health insurance and other insurance

• Proof of paid health insurance premiums (basic and supplementary insurance)
• Receipts for other insurance (household, liability, life insurance)
• List of self-paid medical and accident costs (e.g. dentist, glasses, physiotherapy)

Pension provision

• Confirmation of Pillar 3a contributions (certificate from bank or insurer)
• Confirmation of retroactive Pillar 3a contributions (new from 2026, separate certificate)
• Pension fund contributions (voluntary purchases into Pillar 2)

Deduction options

Professional expenses

• Commuting costs (public transport passes, mileage allowance for car – note upper limit)
• Costs for work equipment (computer, specialist literature, tools)
• Additional meal costs (e.g. for work away from home)
• Home office costs or rent for a separate workspace
• Training and education costs up to max. CHF 12,000 per year

Children and family

• Receipts for childcare costs (crèche, childminder, after-school care)
• Education certificates for children (studies, apprenticeship)
• Maintenance payments (alimony) with corresponding proof

Other deductions

• Medical and accident costs not covered by insurance (note deductible threshold)
• Donation receipts for charitable organisations (keep receipts)
• Maintenance payments (alimony, spousal support)
• Costs for disability-related expenses

Special situations

Self-employed

• Business accounts (balance sheet, income statement, receipts)
• Separation of private and business expenses
• AHV contribution statement for self-employed persons

International connections

• Documentation for foreign properties (imputed rental value, tax assessments)
• Interest and dividend statements from foreign banks
• Proof of foreign tax payments (for double taxation agreements)
• Forms for reclaiming foreign withholding taxes (e.g. DA-1)

Source-taxed persons

• Payslips showing withholding tax rate and amount
• Receipts for additional deductions in case of subsequent ordinary assessment (NOV)

Practical examples

Example 1: Employee in Zurich

Needs: salary statement, account statements, health insurance receipts, Pillar 3a certificate and public transport pass.

Example 2: Family in Bern with property

Additionally: mortgage interest certificate, renovation invoices, childcare receipts and energy renovation certificates.

Example 3: Self-employed businesswoman in Basel

Extended: business accounts, securities lists, insurance receipts, pension contributions and AHV statement.

Common mistakes and tips

Common mistakes

• Not including account statements as of 31 December
• Forgetting insurance premiums or medical costs
• Not keeping donation receipts
• Not declaring cryptocurrencies and digital assets
• Missing certificates for Pillar 3a retroactive contributions (separate certificate required from 2026)

Tips

• Start a document folder at the beginning of the year – preferably digital
• Use online checklists from cantonal tax offices
• Archive all receipts digitally (photos or scans are sufficient in most cantons)
• Clarify open questions with the tax office early
• Use the previous year’s tax return as a template to avoid missing items

Conclusion

A correct tax return requires numerous documents – from income statements to asset details and insurance receipts. Those who carefully collect and submit all documents in an orderly manner benefit from all possible deductions and avoid queries from the tax office.