Pursuant to Art. 61 ABS. 2 AIG, the permanent residence permit expires if the foreign national actually stays abroad for more than six months.
Late return to Switzerland:
If the return takes place after the expiry of six months without the foreigner having requested the retention of the residence permit, the residence permit expires. The same legal consequence occurs if the return takes place after the granted period of retention. In these cases, the foreigner is considered a new entrant and is subject to the general admission provisions of the AIG and the VZAE. However, Art. 49 Abs must be observed.
If a new permit is issued to a foreign national whose settlement permit expired after a stay abroad, the earlier presence or part of it may exceptionally be credited for the period of settlement (cf. Art. 34 Abs. 3 AIG and Art. 61 VZAE).