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 St. Gallen.
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 St. Gallen
For cantonal and communal tax, Art. 39 para. 1 lit. c and para. 2 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.
St. Gallen publishes its own practice: St. Gallen tax book StB 39 no. 7, "Expatriates" (as at 1 July 2011). You can therefore read in advance how the canton reviews the deduction.
How St. Gallen handles the deduction
St. Gallen has its own detailed practice in the tax book. It sets out the underlying logic cleanly: housing costs are normally living costs, not costs of earning income — but that principle cannot be applied unchanged to expatriates. Two points are stricter here than elsewhere: ongoing travel between the home country and Switzerland counts as non-deductible living costs, with only the one-off arrival and return being deductible. And relocation costs when moving on to a third country are not deductible — only the return to the home country counts.
A note on the status of St. Gallen practice
Practice StB 39 no. 7 is dated 1 July 2011 and refers to the ordinance in its version of 3 October 2000. The revision of the Expatriates Ordinance as of 1 January 2016 is therefore not yet reflected in it. That shows in one place: St. Gallen practice also lists as specialists people who were self-employed in their home country and are employed in Switzerland for a fixed-term project. Under the revised ordinance those people no longer qualify — an assignment by a foreign employer is required.
Where cantonal practice and federal law diverge, the current ordinance is the starting point. In practical terms: for a constellation that would only qualify under the old version, it is worth clarifying the position with the tax administration in advance.
Example: when the flat rate comes out ahead
A specialist rents a 2.5-room apartment in St. Gallen at CHF 1,250 net plus CHF 140 utilities and keeps his home abroad. He incurred no relocation costs because the employer paid the move directly.
- Effective housing costs: CHF 1,250 × 12 = CHF 15,000
- Relocation costs: none, as the employer paid directly
- Flat rate: CHF 1,500 × 12 = CHF 18,000
Here the flat rate comes out CHF 3,000 ahead — without documenting individual housing costs. You still have to prove the expatriate status and that the home abroad was kept. Had he also carried relocation costs himself, the calculation could tip the other way.
What to watch for in St. Gallen
The general flat deduction for other professional expenses — in St. Gallen CHF 700 plus 10 percent of net income, capped at CHF 2,400 — is not the same as the expatriate flat rate of CHF 1,500 per month. How the two relate follows from cantonal practice, not from the general provision; clarify in advance if in doubt.
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.