instructions

First log out of your existing Mein o2 account and then follow this description to create a new account with your prepaid phone number (mobile communication)

Then you can check your balance, your consumption, your current pack etc.

You can buy credit (Voucher Codes) in all o2 shops, at gas stations, lottery/tobacco shops, grocery stores, etc. Make sure that you buy an o2 receipt and treat the receipt well so that the code is not damaged.
You can top up the code directly on your cell phone with *103*Vocuher-Code# or in Mein o2.

The o2 shops also top-up the credit directly onto your mobile phone.

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