Details in this link Guide: How to Pay Your Bill (Contract)
This is the method which is part of O2 terms and conditions when you take out a contract phone and is certainly the most convenient way to pay your monthly bill. Account details are given at start of contract and O2 automatically set up direct debit. Paying via direct debit ensures your bill is paid on time. O2 will email the customer the day after the bill is produced. Your account will be debited 14 days later. You can check your bill via My O2
If you haven't got a direct debit and wish to change to this method, then follow the instructions below.
*Phone customer services on 202 and ask them to set up a direct debit for you.
*Print off this Direct Debit Mandate, fill it in and send to the address on the form Direct Debit Mandate
Track usage, upgrade and get support with the My O2 appDownload My O2