Purchase a Swisscom Prepaid SIM card in a Swisscom Shop and apply for number portability at the same time. Be sure to take a valid form of ID with you (ID card, passport or residence permit) for registration as required by law.
Inform your previous provider of the number transfer via SMS: to do so, send a free SMS message using your previous SIM card with the word “JA” to short-dial number 499. This SMS command is the same for all providers and is essential for the transfer of a number.
You will then be informed via SMS about the progress of the porting. The transfer of the telephone number takes at least six working days. Once the number has been transferred successfully, you can replace your previous SIM card with the Swisscom SIM card.
Please note that any remaining balance on your old SIM card will be lost after the porting. Only remaining balances on M-Budget mobiles can be transferred.