Switching phone plans has become a much easier process than it was in the past. Where before you had to go back and forth between your old and new provider, gathering details, now it's just a few steps.
Firstly, you need to know you're eligible to switch plans. If your contract still has a few months until it ends, you are likely to be charged for the remaining time meaning it is usually best to fully finish your contract first.
Switching and keeping your number:
Once you know when your contract is finishing and you've got your new deal, you need to decide if you want to keep your number. If so, you can request a PAC code (Porting Authorisation Code) from your old network. This can be done via the phone or through a text.
Then you simply get in touch with your new provider and give them your new code. Each phone number or text code to get a PAC code is different for each network - all of them list this information clearly on their websites.
Switching with a new number:
Don't want to keep your number - it's even easier! Simply get in contact with your new provider and tell them you want a new number and tell your old network your ending your contract.
This can also be done via a text to switch service. Simply text STAC to 75075.