Filing taxes as a married couple in Switzerland involves a unique set of rules and procedures that differ significantly from many other countries. In Switzerland, the concept of joint taxation is applied, which means the income, wealth, and deductions of both spouses are aggregated into a single tax return. While this simplifies the process to an extent, it also affects the total taxable amount and potentially the marginal tax rate.
This detailed guide walks you through the essential aspects of tax filing for married couples in Switzerland, including who qualifies, what must be declared, how the calculations are done, and tips for maximizing deductions.
Who Must File a Joint Return?
According to Swiss federal tax law, married couples who live together must file a joint tax return. This applies to:
- Civilly married heterosexual couples
- Same-sex couples registered under a legal partnership (prior to marriage legalization in 2022)
- Couples legally residing in Switzerland and cohabiting
If the couple is married during the tax year, the entire year is treated as if they were married on January 1 for tax purposes. In contrast, if a couple divorces or legally separates during the year, they are considered single as of January 1, and separate tax returns must be filed for the entire year.
Key Elements of Joint Taxation in Switzerland
1. Combined Income
The taxable income includes:
- Employment income from both spouses
- Self-employment or business profits
- Investment income, dividends, and interest
- Pensions or annuities
- Rental income from properties
This combined income determines the applicable tax rate, which is progressive. The more income declared, the higher the rate of taxation applied to the top portions of income.
2. Combined Wealth
Wealth tax is levied at the cantonal and communal levels. Both spouses’ worldwide assets are added together and declared as joint wealth, including:
- Real estate
- Bank accounts
- Securities and stocks
- Vehicles and other high-value possessions
3. Shared Deductions and Allowances
The couple can claim various deductions jointly, such as:
- Occupational expenses (commuting, meals, professional training)
- Health insurance premiums
- Childcare expenses
- Contributions to pension pillars (2nd and 3a)
- Charitable donations
- Medical expenses exceeding a threshold
Some allowances, such as those for children or dependents, are calculated on a household basis, rather than per person.
Tax Disadvantages of Joint Filing
While joint filing simplifies administrative work, it may result in what’s known as the “marriage penalty.” This is when the couple’s combined income pushes them into a higher tax bracket than if they had been taxed separately. This issue particularly affects dual-income households where both spouses earn similar amounts.
However, many cantons and federal authorities have introduced deductions or splitting models to reduce the impact of the marriage penalty. For example, the federal government applies a “splitting” mechanism where the couple’s combined income is divided by 1.9 to determine the tax rate, thereby reducing the tax burden.
Taxation of Children and Dependents
Married couples with children may benefit from additional allowances and deductions, including:
- Child allowance (Kinderabzug)
- Education and training cost deductions
- Childcare expense deductions (e.g., daycare, nanny)
- Transport and living cost deductions for children in higher education
These deductions are usually claimed by the parent with the higher income, but they benefit the joint return overall.
Special Cases
1. One Spouse is Taxed at Source (Quellensteuer)
If one spouse is taxed at source (usually foreign nationals without a C-permit) while the other files a regular return, a joint ordinary assessment (nachträgliche ordentliche Veranlagung or nOV) is often mandatory to ensure equal treatment. This allows the couple to file a standard tax return and claim full deductions.
2. Spouses Living in Different Cantons
If spouses live in different cantons, their tax return is usually filed in the canton where the family resides. If they live apart permanently, separate returns may be required, depending on the situation and cantonal law.
3. International Marriages
If one spouse resides abroad, Swiss tax law will consider only the income and wealth connected to the resident spouse but may still require global disclosure depending on the treaty and residency status. The couple may face separate or combined obligations based on treaty terms and income source.
Filing Deadlines and Process
Married couples must submit one joint return by the standard deadlines:
- Federal and most cantons: March 31 of the following year
- Extensions: Typically available until September or November upon request
The return can be filed online using the cantonal e-filing portal or submitted on paper. Many cantons now support electronic tax return platforms (e.g., Zurich’s ZHprivateTax or Geneva’s GeTax).
Required Documents
To file a joint return, married couples should gather:
- Salary certificates (Lohnausweise) for both spouses
- Bank and securities account statements
- Insurance premium statements
- Childcare invoices and receipts
- Confirmation of pension contributions
- Details of rental or self-employment income
- Evidence of charitable donations
- Proof of medical expenses (if claimed)
Tips for Married Couples
- Maximize Pillar 3a contributions by contributing individually (each spouse gets their own deduction limit)
- Track work-related expenses separately for accurate deduction claims
- Consider the timing of income and deductions—deferring income or advancing deductions may reduce joint tax burden
- If both spouses work, monitor the impact on child allowances and childcare deductions
Conclusion
Filing taxes as a married couple in Switzerland involves more than just combining incomes—it’s about understanding the nuances of joint assessment, leveraging deductions strategically, and complying with federal and cantonal rules. While joint filing may not always yield the lowest possible tax bill, proper planning and documentation can help minimize the burden. For complex scenarios, such as international income or source-taxed earnings, consulting a Swiss tax advisor is a smart step to ensure you don’t miss critical deductions or face compliance issues.
Whether you’re newly married or just settling into Swiss life, being informed about how joint taxation works will help you take charge of your financial responsibilities—and opportunities.
