You can change your O2 number in two different situations: you want a brand-new number on your existing contract, or you want to bring a number from another network (or keep yours when switching). The process differs depending on which you need. Both are straightforward, and the first-time change to a new number costs nothing.
If you simply want a different number, call O2 customer service directly. As one member of the O2 Community forum put it: "Call customer service and they will change the number for you. This will be free of charge if it's your first request." O2 can reassign a new number to your existing SIM or account without you needing to do anything else. Keep in mind that any subsequent requests after the first may attract a fee, so it is worth asking O2 to confirm the cost before you proceed.
If you are joining O2 and want to bring your existing number with you, you need a PAC code (Porting Authorisation Code) from your current provider. You give that PAC code to O2 when you set up your new contract, and O2 will transfer the number across to your new SIM.
One Reddit user confirmed this works even when upgrading within O2: they phoned O2 and asked for their old number to be assigned to the new SIM, and it went through without issue.
If you are moving away from O2 and want to keep your number, the process has three steps.
Your PAC code is valid for 30 days, so you have time to sort out the new contract before it expires.
Changing to a new number on your existing O2 contract does not alter your contract terms. Your monthly plan, data allowance and remaining contract length all stay the same. If you are leaving O2 entirely using a PAC code, your O2 contract ends on the day the port completes, so check whether any early exit fees apply before you initiate the switch.
Call 202 free from your O2 mobile, or 0344 809 0202 from any other phone. O2 also offers live chat via the My O2 app if you prefer not to call. Have your account details and proof of identity ready before you get in touch.
## Quotations > Call customer service and they will change the number for you. This will be free of charge if it's your first request. > — Community member (O2 Community forum) (https://community.o2.co.uk/t5/Discussions-Feedback/Change-My-Number/td-p/192495) ## Frequently asked questions ### how much does it cost to change your number on O2 Changing your number on O2 is free of charge if it's your first request. Any subsequent requests after the first may attract a fee, so contact O2 customer service to confirm the cost before proceeding. ### can I keep my old number when switching to O2 Yes, you can keep your old number when joining O2 by obtaining a PAC code (Porting Authorisation Code) from your current provider and giving it to O2 when you set up your new contract. O2 will then transfer your existing number to your new SIM. ### how do I get a new phone number on my O2 contract Call O2 customer service and request a new number. They will reassign a new number to your existing SIM or account at no cost for your first request. ### what is a PAC code and how do I get one from O2 A PAC code (Porting Authorisation Code) allows you to transfer your phone number to another network. The recommended method to get a PAC code from O2 is the 'text to switch' method, which involves sending a single text message. ### can I upgrade my O2 contract and keep my old number Yes, you can upgrade within O2 and keep your old number by phoning O2 and asking for your old number to be assigned to your new SIM. ## Sources 1. [New phone contract, same network (O2), but I wanna keep ... - Reddit](https://www.reddit.com/r/de_EDV/comments/1l26dq4/neuer_handyvertrag_gleiches_netz_o2_aber_ich/?tl=en) (www.reddit.com) 2. [O2 PAC code: keep your number when changing mobile operators](https://5g.co.uk/guides/o2-pac-code-keep-your-number/) (5g.co.uk) 3. [Change My Number - O2 Community](https://community.o2.co.uk/t5/Discussions-Feedback/Change-My-Number/td-p/192495) (community.o2.co.uk)