In the UK, a typical mobile phone contract lasts for two years. This gives networks plenty of opportunity to attract more customers, meaning they are constantly coming up with new deals. For this reason, even those on a pay-as-you-go deal should regularly assess the market to make sure they are taking advantage of the latest offers.
However, when you switch networks, you’ll be given a new phone number, which usually means having to deal with extra hassle. As well as figuring out how to transfer your contacts from one phone or SIM card to another, you will have to let your contacts know of your number change and learn your new number so you can recite it from memory. There’s also the risk of missing an important call from a person or organisation who’s not in your address book because you’ve forgotten to tell them that your number has changed.
If you’ve decided to switch to a network that offers a better deal but you’re wondering how to keep your current phone number, you’ve come to the right place. In this post, we’ll explain how to transfer your number to a new network in five easy steps.
In most cases, it is easy to transfer — or “port” — your mobile number to a new network. Start by checking that your number is eligible for transfer. If so, gather all the necessary documentation (your current and new network information and personal details) and back up your current phone or SIM. You can then initiate the mobile number transfer process.
To do this, you need to request a Porting Authorisation Code (PAC) from your current network, which you then pass on to your new network. Usually, your number will be transferred on the next working day, but it can take two working days if you submit the code late in the afternoon or evening — or even longer if there’s a weekend or bank holiday approaching. To check whether the mobile number transfer has worked, insert your new SIM card into your phone, and try to make a call. If it connects, you will know that the transfer has been successful.
It is easy to transfer your mobile number to a new network. Here’s how to do it in five simple steps:
Step 1. Check eligibility for mobile number transfer
If you have a mobile phone contract, it is important to check when it expires. Most network providers will impose penalties for leaving early, so it might be worth waiting a little longer before switching. Alternatively, you might consider contacting them just before your contract is up to see whether they can offer you a better deal. Most will be happy to reward loyal customers with more minutes and data, low monthly payments or a rolling contract which only locks you in for a short period. Note that if you are changing your number with your existing provider, they will do most of the work for you, so you won’t need to follow these steps. Similarly, if you are transferring your phone number to a different phone or plan within the same network, they will handle everything for you.
If you do decide to change network providers, it’s worth doing some extensive research to ensure you are getting the right deal for you. From SIM-only packages you can change every month to two-year contracts that include the cost of a handset, there are countless mobile phone deals out there. One of the first things to decide is whether you are prepared to be locked into a pay-monthly contract in order to upgrade your current handset or you want a SIM-only deal because you’re happy with your current device. Another point to consider is network coverage is in your area. You can check the mobile availability in your area using Ofcom’s mobile checker. Then, you need to assess your mobile phone usage. If you mainly use your phone for making a high volume of calls and rarely use it for streaming, you will want to choose a deal that offers more minutes than mobile data.
Step 2. Prepare for mobile number transfer
Preparation is key to ensuring your mobile number transfer goes as smoothly as possible. Your life will be much easier if you start getting together all the necessary documentation as soon as you’ve ordered your new phone or SIM card. This includes
- Your current account information
- Your new network information
- Your personal information
If you order your new phone or SIM card online, you may be given the option to start your mobile number transfer there and then. It is usually best to decline this, though, because it is not possible to reverse a mobile number transfer, and there could be a delay with your order, or you may decide to cancel or return it during the cooling-off period. You can use your new, temporary number to make sure everything is working properly before you transfer your preferred mobile number.
It is also wise to back up your current mobile phone and SIM card before you begin the transfer process. This is to give you peace of mind that if the transfer doesn’t go as planned, you will not lose anything. If, for example, your contacts have been saved to your old SIM rather than your device, you will lose them when the number transfer takes place.

Step 3. Initiate the mobile number transfer process
To transfer your mobile number to a new network, you will need a PAC code. You can request this for free from your current network provider, who should be able to provide it in less than one minute. If you don’t receive it within two hours, you can lodge a complaint with Ofcom, as this is the time frame they have stipulated.
When requesting your PAC code, you don’t need to speak to anyone on the phone. The easiest way to request your code is to use the Text to Switch service by texting “PAC” to 65075. Alternatively, you can request it in the following ways:
Mobile provider | Contact |
BT Mobile | Call 150 from a BT mobile phoneCall 0800 800 150 from any phone |
EE | Call 150 from an EE mobile phoneCall 07953 966 250 from any phone |
giffgaff | Request in user account |
iD Mobile | Call 7777 from an iD Mobile phoneCall 0333 003 7777 from any phone |
Lebara Mobile | Call 5588 from a Lebara Mobile phoneCall 020 3059 0304 from any phone |
O2 | Call 202 from an O2 mobile phoneCall 0344 809 0222 from any phone |
Plusnet Mobile | Call 500 from a Plusnet Mobile phoneCall 0800 079 1133 from any phone |
Sky Mobile | Call 03300 412 524 from any phone |
Smarty | Request in user accountEmail [email protected] |
Tesco Mobile | Call 4455 from a Tesco Mobile phoneCall 0345 301 4455 from any phone |
Three | Call 333 from a Three mobile phoneCall 033 333 81001 from any phone |
Virgin Mobile | Call 789 from a Virgin Mobile phoneCall 0345 6000 789 from any phone |
Vodafone | Call 191 from a Vodafone mobile phoneCall 033 3304 0191 from any phone |
VOXI | Request in user accountCall 0808 004 5205 from any phone |
Normally, a PAC is an alphanumeric code made up of nine digits, so it is wise to write it down and keep it somewhere safe until you need it.
Note that once your PAC code has been issued, it is only valid for 30 days, so if it expires before you’ve had a chance to use it, you will need to request a new one.
Step 4: Give your PAC code to your new network
Next, it’s time to give your PAC code to your new network. When you do this varies, depending on your new provider. Some may request it when you sign up, while others will ask you to get in touch as soon as you have it.
Once you submit your PAC code, the transfer will begin automatically. You can usually submit it online, but you can also do it over the phone if you prefer.
Your new network will then book a time for the transfer, which is usually the next day. If you submit your code late in the afternoon or in the evening, you may have to wait two days, and if there’s a weekend or bank holiday coming up, it will be the next working day.
While you are waiting for the transfer to take place, continue using your old SIM card, as this is the one that will have service.
On the day of the transfer, you must make sure you are in the UK. You will be notified by text message when the process starts and when it is complete. During this time, you will lose coverage on both networks and will need to restart your phone with your new SIM inside it to regain coverage and complete the phone number transfer.
Step 5: Check the transfer has been successful
The last step is to check whether the mobile number transfer has worked.
To do this, try to make a call using your new SIM card. If the call connects, you will know that the transfer has been successful.
Unfortunately, you may find that your mobile number transfer request is delayed or rejected. This is usually caused by supplying the wrong information or trying to do something that’s not possible.
To make your phone number transfer go as smoothly as possible, here are some things to bear in mind:
Requesting your PAC code
There are various codes associated with mobile phones, which means things can get confusing.
A Service Termination Authorisation code (STAC), for example, is used if you want to switch network providers without keeping your current phone number. A STAC code terminates your contract, leaving you free to sign up with another provider.
Personal Unblocking Key (PUK) codes are also sometimes confused with PAC codes, especially since they sound similar. PUK codes are used when a handset gets blocked — which can happen if you enter your passcode incorrectly three times.
So, when requesting your PAC code, it is important to ensure you are asking for the right one.
Transferring a number on the same network
If you want to transfer your number to a different deal with the same network, your mobile number transfer request may get rejected. This could be because you’re signing up for a ‘new customer’ deal rather than upgrading.
You may be able to work around this by transferring your phone number to a different network and then transferring it back to your original network.
Transferring a pay-as-you-go number
You can transfer a pay-as-you-go number to a different network by following the above steps, but you cannot transfer credit to a different network. This means any unused credit will be lost on the day of your mobile number transfer.
Therefore, it is wise to use up any credit before the transfer takes place. Alternatively, you might consider donating it to a charity like Cancer Research, Red Cross or Save the Children.
Transferring business numbers
Businesses can also follow the steps above to transfer mobile numbers, but there is a limit of 25 numbers.
Those wanting to transfer more than this amount will need to arrange it with their network instead.
Other issues
If you are experiencing other issues, it may be because what you are trying to do is not possible. Some examples of this are:
- Swapping phone numbers between networks — This is not possible because when you transfer your number to a new SIM card, the original number on that SIM will be lost.
- Transferring a lost number — If your phone number has been cancelled, for example, due to inactivity or a cancelled contract, it will be lost and cannot be transferred to another network.
Any other issues regarding your number transfer should be dealt with by your new network provider. If, for example, there is a delay with your transfer or you are experiencing problems with your phone after the transfer, you may be entitled to compensation.
Conclusion
In most cases, it is easy to transfer a mobile number to a new network. Follow these five steps:
- Check your eligibility for a mobile number transfer
- Gather all the necessary documents and back up your device and SIM card
- Initiate the mobile number transfer process by requesting a PAC code
- Give your PAC code to your new network
- Check the transfer has been successful
Unfortunately, you may find that your mobile number transfer request is delayed or rejected. This is usually caused by supplying the wrong information or trying to do something that’s not possible.