Preventing expiry of prepaid SIM and/or credit

NFH

I am an occasional visitor to Switzerland and currently have an Orange CH prepaid SIM card. Because Orange want CHF40 to replace my SIM card for nano-SIM for my iPhone 5, I'm considering moving to Swisscom, particularly as Swisscom's charges are now the same, if not lower, than Orange's.

I have one question though, to which I cannot find the answer on the Swisscom web site. Are there any requirements to prevent a Natel Easy SIM card or its credit from expiring? I have SIM cards from many countries and the most common requirements are the following:

Increase the credit periodically, i.e. top up (not suitable for a non-resident)
Increase or decrease the credit periodically
Use the SIM periodically, including free usage such as receiving calls or texts

Which of these three policies does Swisscom use to prevent a prepaid SIM card from expiring?

Athmos

Hi NFH

Look the information on the following site.

Athmos

NFH

Thanks Athmos. This is exactly the information I needed. It's interesting (but not disappointing) that top-ups don't prolong the expiry. Requiring only chargeable usage is convenient for non-residents.