1) Check you’re eligible to switch from giffgaff
Assuming you’re out of contract, it won’t cost you anything to leave giffgaff. If you’re not sure whether you’re still under contract or want to find out your contract end date, you’ve got a few options.
The first is to log in to your account at giffgaff’s site.
The second is to log in to the giffgaff app on your phone.
As you’ll almost certainly know, giffgaff doesn’t operate a telephone customer support service. So you won’t be able to get in touch over the phone.
2) Contact giffgaff to cancel your contract and get a PAC Code
With your phone wending its way to you, you’ll now need to contact giffgaff to tell them you’d like to leave and get a PAC Code. A PAC is a short, alphanumeric code, which is critical for transferring your number to the network you’re joining.
You can get your PAC code from giffgaff by logging into your account online and requesting one.
Or you can get one by texting 43431 from your giffgaff phone.
All networks are obliged to supply your PAC within two hours of your request. Once you’ve got it, you may want to make a note of it. Just in case.
PAC Codes are valid for 30 days only. If you haven’t used yours within this timeframe, you’ll need to submit a request to giffgaff for a new one.
3) Find and buy a new phone or SIM deal from Three
Out of contract and ready to switch? Good news. Your next task is to sign up for a new phone contract or SIM only deal from Three. Once you’ve passed Three’s credit checks, you’ll receive your phone in the post.
4) Contact Three to give them your PAC code
We’re almost there now. Next you’ll just to ring Three to give them your PAC. You can reach their customer support team on 0333 338 1001 from a landline (standard network rates apply).
5) Insert your new Three SIM card
If you got a new phone as part of your contract, take the pin-key included in the box and unlock the handset's SIM tray. Then insert your Three SIM card.
If you went for a SIM-only deal instead, you can just put the Three SIM in your existing phone.
While the number transfer is taking place, you’ll be given a temporary phone number that you can use and on which people can contact you.
6) Wait for your number to be transferred
The transfer should be complete the next working day. However, this can vary from network to network and sometimes depends on whether the day after you make your call is a working day or a weekend.