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 Aargau.
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 Aargau
For cantonal and communal tax, Art. 35 para. 1 lit. c 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.
Aargau does not publish extensive separate guidance like Zurich or Thurgau, but its tax information on expatriates refers expressly to the federal Expatriates Ordinance. The ordinance and the general provision on professional expenses are therefore what applies. An overview of the cantonal rules on professional expenses is available in the canton's tax portal.
How Aargau handles the deduction
For assignees in Aargau that means the canton forgoes detailed rules of its own and points directly to the ExpaV in its tax information. The cantonal statutory basis remains Art. 35 para. 1 lit. c of the cantonal tax act — the ordinance supplies the detail. Questions about reasonableness or evidence are therefore not answered by a cantonal information sheet; they have to be developed from the wording of the ordinance and the individual case.
Example: housing plus relocation in the first year
An assignee rents in Aargau at CHF 2,600 net plus CHF 210 utilities. In the first year she also carried relocation costs of CHF 4,000 herself.
- Effective option: CHF 2,600 × 12 = CHF 31,200 housing plus CHF 4,000 relocation = CHF 35,200
- Flat rate: CHF 18,000 — covering housing, relocation and travel together
- Not possible: the flat rate plus effective relocation costs on top
This is exactly why you cannot simply compare the monthly rent against CHF 1,500. What counts is the total of all effectively deductible costs — and in the year of arrival and the year of departure it can be higher than in the years in between, because of the relocation costs.
What to watch for in Aargau
Many assignees living in Aargau work in Zurich or Basel. The canton of residence governs the deduction, not the place of work — and because Aargau publishes no detailed practice of its own, comparing with the federal direct tax assessment is particularly useful here.
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.