It’s one of the questions that comes up most often in the group when someone signs a new contract: “Do I need to update my licence? Do I need to apply for anything? Is there a risk of losing it?” The answer is that it depends on each person’s individual circumstances, but there are specific rules it’s worth knowing before signing.
If you are a European citizen with a B permit, in principle you are free to change employers as long as you hold the free movement permit. What you must do, however, is notify the cantonal immigration office. This is not an application for authorisation, but a notification; nevertheless, it is compulsory. In practice, many people do not do this and nothing happens for years, until something does: a renewal, a formal procedure, and they discover that something does not add up in their record.
Changing cantons is a slightly different matter. If you are moving to live and work in another canton, the new canton will take over the administration of your permit. You must register with the new commune, and from that point onwards, the cantonal migration office in your new region will handle your file. The type of permit does not change, but the process requires you to complete the formalities correctly and in the correct order. As for the C permit, in principle it is not affected by a change of employer: it grants full freedom to work throughout Switzerland, without the need to notify the authorities of a change of employer, although it is advisable to notify them of any change of address.
Switching from full-time to very part-time work does not directly affect the European Category B driving licence, but it can have consequences in other areas: tax at source, social security benefits and unemployment insurance conditions. It does not affect the licence itself, but it does affect the circumstances surrounding it. And many people only realise this when they are faced with an unexpected surprise.