Top up between £10 and £30 online. You'll just need your mobile number and a credit or debit card handy.

Your card will need to be from a UK bank and registered to a UK address. You can only top up in pounds, not pence.

Top up now

Auto top-up makes sure you never run out of credit by automatically topping up with money from your credit or debit card.

Step 1: Sign in to My O2 to set up your auto top-up.

Step 2: Choose the amount and if you want to get topped up on a certain day/date or when your balance gets low.

Step 3: We'll then top you up automatically. You can change or cancel whenever you like.

Call 4444 free from your mobile, or 08456 062 277 from a landline. Have your debit or credit card handy and follow the simple instructions.

Your card will need to be from a UK bank and registered to a UK address. You can only top up in pounds, not pence, and top-ups start at £10.

To top-up, hand over your e-top up card at any O2 shop or other store with the green top-up logo. You can pay by cash, credit or debit card and can top up between £10 and £50. You can also use the same card again and again.

Go to any O2 shop or anywhere you see the green top-up logo and ask for an O2 top-up. You can pay by cash or card. Then call 4444 free from your mobile, or 08456 062 277 from a landline, enter the number on your receipt and follow the instructions. Top up between £10 and £50. Your voucher will expire after twelve months.

Call 4444 free from your mobile anywhere in the world. If the country doesn't allow shortcode dialling, enter *111*# and press the call button. Have your debit or credit card handy and follow the instructions. You can also use top-up vouchers abroad. Or top up online using Web top-up.