Cancelling a contract via telefon does not work! They say that it`s cancelled, but keep taking money from my account. There is no possiblity to find a mail or postadress to cancell on their website: What if I want to leave Three? Cancelling your contract. We're sorry to hear that you're thinking of leaving us. Whatever the reason, we would like to talk to you before you make any decisions. Please give us a call free on 333 from your Three phone or 0333 300 3333 (standard rates apply) , so we can look at the best options for you. Our lines are open 9am - 6pm. Here's some important information you need to know before you call us: You'll need to give us 30 days' notice from the end of your contract term if you want to end your contract. You don't have to put it in writing, we can do it all over the phone. If you're thinking of leaving us before the end of the contract period you committed to when you joined or renewed, there will be a charge. If you're not sure about this we can explain more when you call. If your Three device has been lost or stolen, there's no need to cancel, just let us know straight away. We can protect your account from misuse, sort out a replacement, and get you back up and running quickly. If you want to cancel under our returns policy there are some rules. Find out about our full returns policy. Cancelling a SIM plan. You can cancel your SIM plan at any time but you'll need to give us 30 days' notice from the end of your contract.