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People from abroad working in Switzerland have tax deducted directly from their income (tax at source). Foreigners who live in Switzerland and have a residence permit (permit C), however, need to declare their income and assets in a standard tax return.
Tax is deducted directly from your salary. Your employer will do this automatically if you are a foreign worker and:
If you are a foreign worker resident in Switzerland for tax purposes and your income exceeds a certain limit, a statutory assessment of your whole income and assets will be carried out. This limit is CHF 120,000 for the Confederation and in almost all cantons.
The tax at source rate differs from canton to canton. You can get more information from the tax office in your canton.