What is a PAC number? It is the Porting Authorisation Code that lets you switch mobile network and keep your phone number. Here is how to get one free by text, and what the banking version means.
If you are switching mobile network but want to keep your phone number, a PAC number is the thing you need. It is a short code that tells your new provider to bring your existing number across, so your contacts can still reach you on the same digits. The good news is that getting one takes about a minute and costs nothing. Here is what a PAC number is, how to get yours, and how to use it, plus a quick note on the completely different banking meaning that some people are searching for.
PAC stands for Porting Authorisation Code. It is a unique code linked to your mobile number that authorises your number to be transferred, or "ported", from your current network to a new one. Without it, switching networks would mean getting a brand new number. With it, you keep the number you already have. You only need a PAC if you want to take your number with you. If you are happy to start fresh with a new number, you do not need one at all.
Since 2019 the process has been refreshingly simple. You do not have to call your provider or sit through anyone trying to talk you out of leaving. Instead, you request your PAC by text:
That last point is worth reading carefully before you switch, since leaving mid-contract can come with a cost.
Once you have your code, the switch itself is handled by the network you are joining. You sign up with your new provider and give them your PAC, and they arrange to move your number across. A few things are worth knowing:
It is a similar idea to changing broadband supplier, where your new provider does the legwork, which we cover in our guide on how to switch broadband provider.
If you are leaving a network and do not care about keeping your number, you do not need a PAC. Instead you can text STAC to 75075 to get a Service Termination Authorisation Code, which lets you cancel and walk away without porting your number. And if you just want the facts before deciding, you can text INFO to 85075 to get switching information, including any charges, without committing to anything.
A mobile PAC is not a simple five-digit number. It is usually a code of around nine characters that mixes letters and numbers, generated specifically for your number when you request it. If you have seen a "five-digit PAC" mentioned, that almost always refers to the banking meaning of PAC, which is a separate thing entirely, covered next. For switching your mobile, just request the code by text and use whatever code you are sent rather than worrying about its exact length.
Confusingly, PAC means something else in banking. Here it stands for Personal Access Code, a security code used to log in to online and mobile banking with certain banks. AIB, for example, uses a PAC as a five-digit Personal Access Code that you enter alongside your registration details to access your account. This is why searches for a "5 digit PAC number", an "AIB PAC number" or a "PAC number for banking" appear. It has nothing to do with mobile switching. If you are trying to log in to your bank, your PAC is the personal login code you set up with them, and if you have forgotten it you should reset it through your bank's official app or website rather than anywhere else.
To bring it back to the most common reason people ask: on a mobile phone, your PAC is the code that lets you switch network and keep your number. Text PAC to 65075, read the reply for your code and any charges, sign up with your new provider, and hand the code over. Your number moves across, usually within a working day, and you carry on as normal. The whole point of the system is to make switching easy, so you are free to chase a better deal without losing your number.
Switching mobile networks is one of the simplest ways to cut your monthly costs, and the PAC system means there is no longer any reason to stay put just to keep your number. You can read the official rules on switching mobile provider from the regulator, Ofcom.
A PAC number, or Porting Authorisation Code, is a code that lets you switch mobile network while keeping your existing phone number. You give it to your new provider, who uses it to transfer your number across.
Text the word PAC to 65075 from the phone you want to switch. It is free, works on any UK network, and you usually get a reply within a minute containing your code and details of any charges for leaving.
A five-digit PAC is not the mobile switching code, which is longer and mixes letters and numbers. A five-digit PAC usually refers to a Personal Access Code used to log in to online banking, such as with AIB, which is a separate thing entirely.
In banking, PAC stands for Personal Access Code, a security code used to log in to online and mobile banking. AIB uses a five-digit PAC alongside your registration details. It is unrelated to switching your mobile number, and you reset it through your bank if forgotten.
A mobile PAC is valid for 30 days from the day you request it. If you do not use it to switch within that time, you can simply text PAC to 65075 again to get a new one.
Only if you want to keep your current phone number. If you are happy to take a new number, you do not need a PAC, and can instead text STAC to 75075 to cancel your old service without porting your number.
On a mobile phone it is the code that moves your number to a new network. Text PAC to 65075, give the code you receive to your new provider, and your number transfers across, usually within one working day.