Switch from Three to O2 and keep your number using a PAC code
Ofcom’s policies have made it extremely quick and easy to switch and transfer your Three number to O2.
It’s completely free to transfer your number - you simply need to request a PAC code from Three by sending a text message, which takes no more than 2 minutes to arrive. Once you’ve handed the PAC code to O2, the switching process will take no more than 1 to 2 working days to complete.
If you want to join O2 and get a brand new phone number, without keeping your existing Three number, the process is almost identical - the only difference being you will need to request a STAC code instead of a PAC code.
Joining O2 from Three
Joining O2 and transferring your number from Three is a very easy process, and should take no more than 1 to 2 working days.
You simply need to request a free PAC code from your Three number, and hand it to O2.
You can hand your PAC code to O2 at the time of ordering a new O2 phone or O2 SIM, or you can do this after you’ve received your order. When you choose to do this is up to you - it doesn’t make a difference.
After you’ve handed your PAC code to O2, your number will be transferred to O2 within 1 to 2 working days, and your account with Three will automatically be closed.
1. Request a PAC code from Three
Requesting a PAC code from Three is quick and free. The easiest way to do this is via text:
- Text: From your Three number, text PAC to 65075 for free. You will receive a reply within 2 minutes, containing your PAC code
- Online: Request to leave Three by logging into your account
- Phone: Call 333 from your Three number or 0333 338 1001 from any other number
- Monday to Friday: 8am to 8pm
- Saturday & Sunday: 9am to 6pm
- Store: Locate your nearest Three store and ask to leave
You will have 30 days to hand your PAC code to O2, after which it will expire and you will need to request another one from Three.
Note: If you wish to switch to O2, but you want a brand new number without keeping your Three number, you need to request a STAC code rather than a PAC code from Three. You can do this by texting STAC to 75075 instead.
2. Order a new phone or SIM from O2
If you haven’t yet ordered a new SIM or phone with O2, you can find the cheapest O2 deals through our comparison tools:
You can also find a full range of contracts from O2’s website.
You may have the opportunity to hand your PAC code over at the time of ordering a new phone or SIM from O2. If so, you will have the option to enter your PAC code during the checkout process. Once your order arrives and you activate the SIM, the transfer process will automatically begin.
If you’re not given the opportunity to hand your PAC code to O2 at the time of ordering, don’t worry. Instead, you will receive a temporary number with your new O2 SIM. You will be given the opportunity to hand your PAC code to O2 and transfer your Three number once your order arrives, as detailed in the next step.
Note: Apart from being slightly more convenient, it doesn’t make a difference whether you choose to hand your PAC code to O2 at the order checkout or after you’ve received your order.
3. Hand the PAC code to O2
Once you have your PAC code from Three, you simply need to hand it to O2 to start the transfer process.
If you previously handed your PAC code to O2 at the time of ordering a new O2 phone or O2 SIM during the checkout process, you can skip this step.
Handing your PAC code to O2 can be done through a number of ways:
- Online: Fill in the online form and enter your PAC code
- Phone: Call 202 from your O2 SIM or 0344 809 0202 from any other number.
- Monday - Friday: 8am - 9pm
- Saturday: 8am - 8pm
- Sunday: 8am - 6pm
- Store: Locate your nearest O2 store and ask to join O2
4. Wait for the switch to O2 to complete
After you’ve handed your PAC code to O2, they will notify Three that you wish to leave them and transfer your number to O2.
It will take 1 to 2 working days for O2 to transfer your number. Once the transfer has completed, your account with Three will automatically be closed.