I have an Iphone 5C on contract with EE at the moment, contract ends 30th of May, so if I contact EE at the end of April giving 30 days notice, will they ignore the demand like 3 did 7 years ago and I then had to get Dad to ring up and threaten their Indian call centre with legal action?!

I need to terminate the contract in April for May, as Dad's buying me a new phone outright for my 40th, no contract.

The surest way to terminate these days is to get a PAC code and use it a day or 2 before the end of your contract, so ring up at the end of April and tell them you want to leave and ask for your PAC. Then you ring up your new network on the 27 or 28 of April and give them the PAC to transfer your number, making sure you do it on a business day and there are at least 2 business days left before the end of the month. As soon as your number is live on the new network the old account at EE will be terminated and you will only pay till the end of the 30 days from the day you asked for the PAC number.

Thanks for that

Are you moving to a different network for sim only? Otherwise why not ring EE and see what sim only deals they can do for you?

The best way to terminate if you aren't taking your number with you is to do so in writing by recorded delivery so you have proof the notice was received. This prevents the "lost in the post" issue the OP's father had and also prevents the issue of phone agents not acting on terminations and then there being no proof of the phone call

If you are porting your number there is no need to do this and you should follow the advice above as porting will automatically disconnect the old account once it goes over

Not sure, I've given Dad and my Brother an idea of what phone I want but other than that I have no input into it, and yes I am porting my existing number to the new phone, which will possibly be on Talk Talk.

EE will send a text message confirming your cancellation at the end of your phone call. It will confirm the date your service ends. This is all the proof you need. There's no need to use recorded post. And many large companies refuse to sign for them anyway.

And even if they do sign for the letter all it proves is you sent SOMETHING to them, it could have even been an empty envelope. It doesn't really prove anything if the network disputes receiving a cancellation letter.

The suggestion of sending the letter as Recorded Delivery is just a total waste of money, if you are insistent on writing to them, legally a FREE Post Office Horizon Proof of Posting counts for the same evidence in court if it was ever needed.