Keep my Three number
How to get a PAC code from Three & transfer my number to O2
Request your Three PAC code by calling Three customer service on 333 from your 3 Mobile handset or by dailling 0333 338 1001 from any other phone or landline, and ask for your 3 PAC code or "Port Authorisation Code".
If you wish to use the 'text-to-switch' service, simply SMS text
65075 free from your Three SIM to
get your Three PAC code by text message and begin the porting process.
- Three will provide your PAC code (Porting Authorisation Code) either by SMS text message, via email, or over the phone if you contact them.
- A PAC number is valid for 30 days. If you don't use it within thirty days it will expire and you will need to request a new one.
- Your Three account will remain active until your number has been ported over to your new O2 network. After the transfer is complete, your old Three account will be automatically closed.
While you wait to get your Three PAC code, find the best O2 online offer for you. Many of these exclusive mobile phone deals are only available online, directly from the network providers listed here.
Got your Three PAC code?
Provide your PAC code from Three to O2 who will then be able to port your existing Three number. They will tell you what day the transfer is due to take place (usually within 48 hours).
Important: Do NOT cancel your SIM only or mobile contract before switching, otherwise you may lose your current phone number and be unable to port it over. Once you give O2 your Three PAC code, your old Three billing account will be closed automatically when your mobile phone number is successfully ported over.
Note: Credit on Pre-Pay / PAYG (Pay-As-You-Go) accounts cannot be transferred over and so any remaining credit balance will be lost after the switch is complete. If you have any credit left, one good option is to donate it to a charity by SMS text message before porting your number.
Transfer my number to O2
How to switch to O2 and keep my Three number?
First get your O2 package and activate your new SIM card.
Once you have done that, get the following information ready to follow the step-by-step instructions:
- Your old Three mobile phone number that you want to keep.
- The Three PAC code (Porting Authorization Code) from your previous network.
- The expiry date of the PAC number (valid for 30 days from the date of issue).
- The temporary mobile number from your new O2 SIM card activation.
- You may also need the new O2 SIM card serial number found on the back as an additional security check.
Contact O2 customer services with your PAC code and let them know you wish to transfer your old number to O2. You can reach them either from your 02 mobile phone on 4445 for Pay As You Go, or 202 for Pay Monthly contracts.
If you are calling from a landline: dial 0344 8090222 for Pay As You Go customer Service or 0344 8090202 for Pay Monthly customer Service.
Alternatively, you can fill in the online O2 form and they will contact you when the transfer is complete.
Note: You may lose network service for a short period on the day of transfer. If this happens, turn your phone off and on occasionally, until you see the O2 signal on your mobile phone screen. This will indicate that the transfer is complete, and you can now use your old phone number in your new mobile network provider.