Self-employed on a B, C, L or G permit? It mostly depends on your passport.

Swiss passport or C settlement permit: you can work anywhere in Switzerland, employed or self-employed. Nothing else is needed.

Family members from outside the EU and EFTA who are allowed to work under Art. 46 of the Foreign Nationals Act need no extra procedure either.

The free movement agreement applies to you.

• B permit, employed until now: switching to self-employment needs neither authorisation nor a notification.
• Moving to Switzerland to set up on your own: you get a B permit for at least five years once you show that you work as self-employed. If the proof is still uncertain, Zurich can first grant a permit for six months so you can provide it.
• L permit: you have to report the switch to self-employment, and you need a new B permit for it. Self-employed people don't normally get an L permit.
• G permit, cross-border: you can be self-employed in Switzerland. You file a certificate of residence from abroad and a copy of your passport or ID, and you go home at least once a week.

The proof often rests on SVA Zürich recognising you as self-employed. The order is then: SVA first, then the B permit.

With a B permit from a country outside the EU and EFTA, switching to self-employment needs authorisation. In the canton of Zurich, the cantonal Office for the Economy (Amt für Wirtschaft, AWI) reviews the application. Among other things, it checks whether there's an economic interest and whether the financial and business conditions are met.

You need the authorisation before you start, not after.

Some professions are regulated and also need a professional licence, in health care for example, through the canton of Zurich's Health Directorate. That licence never replaces your residence permit. You need both.