on 29-05-2017 16:32
If you have a Refresh contract you just need to pay off the device then give 30 days notice for the airtime.
If a standard 24 month contract you pay the number of months remaining multiplied by your monthly tariff.
on 29-05-2017 16:36
How to leave here https://community.o2.co.uk/t5/Pay-Monthly-and-Pay-Go/Cancelling-Your-Contract-A-Guide/m-p/566774/hig...
OnePlus 6 (O2 & Sfr), Z3 Tablet (Three UK), iPhone7 (EE)