What this is about
People posted to Switzerland for a few years often pay twice: the home abroad keeps running, and a second one is added here. Swiss tax law has a deduction built for exactly that — the special professional expenses of expatriates. How it works in general is set out in our guide to the deduction. This article is about the canton of Thurgau.
Who counts as an expatriate
Before the cantonal level matters at all, the basic condition has to be met. Art. 1 para. 1 ExpaV covers two groups: managers and specialists with particular professional qualifications who are posted to Switzerland temporarily by their foreign employer. Not everyone who comes to Switzerland on a fixed-term basis meets that test.
What "temporary" means is set out in Art. 1 para. 2 ExpaV: employment limited to a maximum of five years. And under Art. 1 para. 3 ExpaV the deduction falls away in any case where fixed-term employment is replaced by permanent employment — even if the five years have not been used up.
The legal basis in Thurgau
For cantonal and communal tax, Art. 29 no. 3 of the cantonal tax act applies — the provision on the other costs required to carry out your profession. The special professional expenses of expatriates are given shape by the federal Expatriates Ordinance, which applies directly to federal direct tax.
Thurgau publishes its own practice: Thurgau tax practice StP 29 no. 16 on special professional expenses of expatriates (as at July 2024). You can therefore read in advance how the canton reviews the deduction.
How Thurgau handles the deduction
Thurgau publishes its practice in the cantonal tax practice collection and updated it in July 2024, making it one of the most current in the series. It states expressly that the flat rate of CHF 1,500 per month covers housing, travel and relocation costs but not schooling costs, and that the home abroad must be documented.
Example: with children in a private school
An assignee family lives in Thurgau at CHF 2,300 net plus CHF 180 utilities. Both children attend a foreign-language private school because the public schools offer no adequate teaching: CHF 16,000 a year.
- Effective housing costs: CHF 2,300 × 12 = CHF 27,600
- Or the flat rate: CHF 18,000 for housing, travel and relocation
- Schooling costs: CHF 16,000 deductible on top, provided the conditions are met and the costs are documented
Schooling costs sit outside the flat rate — but not outside the conditions. In particular, the public schools must offer no adequate teaching — the wording used by the ordinance and by Thurgau practice; meals, transport and childcare do not count.
What to watch for in Thurgau
Keep the lease or ownership document for the home abroad at hand and document that it was not rented out. Thurgau practice requires this evidence expressly — including when you only claim the flat rate.
Regardless of canton, it is almost always the same points that cost people the deduction: gross rent claimed instead of net rent, the wrong provision cited, rate determination overlooked when arriving or leaving mid-year, or the home abroad left undocumented. The details are in our guide to the deduction, and what applies to travel and relocation costs is in the article on those.
Who carried the costs is decisive
What matters is who bears the costs economically and how any employer reimbursement is treated for tax purposes. An actual reimbursement against receipts generally rules out an additional deduction. Where a lump sum is paid and added to taxable gross salary in the salary statement, a deduction remains possible.
Every case is different — the potential usually is not
Whether and how much you can deduct depends on your situation: how the assignment is set up, your employment contract, your housing situation abroad, and who actually carried the costs. This article sets out the principles and a simplified example; it does not replace individual advice. What does generalise: on fixed-term assignments, deductions are regularly left on the table — a second look is almost always worth it.