The O2 phone number is 0344 809 0202, and you can use this for an O2 cancel contract request, to ask questions about O2 promo codes, or to make any other kind of query relating to your phone and account.
Use your online account to speak to the team on live chat, or go into a retail location for assistance.
You can make an O2 online top up onto your account via the website, by calling 4444 from your phone or by setting up an auto top-up.
You can buy O2 contracts online too.
Look out for O2 promo codes that save you more!
The O2 network coverage can be checked online at any time to see what current coverage is available in your area.
Buy an O2 sim only for an existing contract online or in-store, and find out more about O2 wifi calling in the product demo area.