Can I keep my landline number when switching broadband? UK guide

Yes. In most cases you can keep your existing landline number when you switch broadband provider, and you don't have to lift a finger to move it yourself. The process is called number porting, and under Ofcom rules your current provider has to release your number to your new one where it is technically possible. Porting itself is free, and it usually happens as part of the switch rather than as a separate job you have to arrange.

The rest of this guide explains how that transfer works, what the move from copper landlines to digital voice means for your number, how it differs when you move house, and the handful of situations where your number might not travel with you.

How landline number transfer works

Number porting is the process of moving your existing landline number from one provider to another. Ofcom's number portability rules require communications providers to support customers who want to transfer eligible numbers between services where it is technically possible. Your current provider cannot refuse to release your number or hold it hostage. Keeping a number when you change provider works on the same principle as keeping your mobile number when you change network.

Since September 2024, most broadband and landline switches in the UK are handled through One Touch Switch. Under these rules your new provider manages the whole move, including cancelling your old service, so you deal with one company rather than two. The number port is processed at the same time, which means your landline number transfers when your new broadband goes live.

The key thing to get right is that your number must still be active on your current account when the switch happens. If you cancel your old service first, the number can be released back into the pool and lost. Keep the old line running until your new broadband and landline are confirmed working.

What the PSTN switch-off means for your landline

The old analogue landline network, the Public Switched Telephone Network (PSTN), is being retired. According to government guidance, all users of the Openreach PSTN need to be migrated to new digital services by 31 January 2027. The upgrade is being delivered by the telecoms industry, and it is the reason porting matters now: nearly everyone will end up on a digital line whether they switch provider or not.

After the switch-off, calls travel over your broadband connection rather than down copper wires. This is often called digital voice or VoIP (Voice over Internet Protocol). Instead of plugging your phone into a wall socket, you plug it into your router. Many modern routers have a telephone port on the back for exactly this. Different providers brand the service differently: BT calls it Digital Voice, Sky calls it Sky Talk, and Virgin Media calls it Virgin Phone, but the underlying service is the same.

The important point is that the switch-off changes the technology, not your number. Your existing landline number can stay the same and can still be ported. The digital switchover does not automatically assign you a new number.

Digital voice brings a few benefits over an analogue line. Call quality is often clearer, and you can use features such as call forwarding to your mobile, spam call blocking and three-way calling. But because the service depends on your broadband and mains power, calls will not work during a power cut. Ofcom requires providers to offer a solution, usually a battery backup unit or, for vulnerable customers, a free mobile handset. If you or a family member relies on a personal alarm, care line or pendant service, raise this with the provider before you sign up.

Keeping your number when moving to full-fibre (FTTP)

Full-fibre, or FTTP (Fibre to the Premises), runs a fibre connection all the way to your home and does away with copper entirely. Because there is no copper phone line, your landline has to move to a digital voice service to survive. The good news is that it can. You can port your existing number to the digital service that runs over your fibre connection, so moving to full-fibre does not mean giving up a number you have had for years.

As with any switch, provide your new provider with the exact number you want to keep and leave the old service active until the transfer is done. One thing to expect with fibre: if engineering work is needed to install the FTTP line, the overall changeover can take a little longer than a standard switch.

Switching provider versus moving house

These two situations often get muddled, and they behave differently.

When you switch provider at the same address, you can usually keep your number without trouble. Your new provider arranges the transfer and you don't need to contact your old one separately.

When you move house, whether you keep your number depends on where you are moving to. UK landline numbers are geographic and tied to a local telephone exchange. If you move within the same area, you can normally keep your number. But if you move to a different area with a different code, the number usually cannot travel with you. Moving from London (020) to Manchester (0161), for example, means your London number is tied to the London exchange and you will likely need a new number with the local code.

If you are attached to an old number you cannot port, one workaround is to set up call forwarding from the old number to your new number or mobile for a period, so you don't miss calls while people update their records.

How to request your number transfer step by step

The process is straightforward and mostly handled for you:

1. Choose your new provider and confirm they support landline number porting before you sign up. Most major providers do, but smaller or mobile-only broadband services may not offer a landline at all.
2. Tell them you want to keep your existing number when you place the order. This is the moment to say it, not after the switch.
3. Give them accurate account details. They will typically need your full landline number including the area code, your current provider's name, the account holder's name exactly as it appears on the bill, and your service address. A recent bill or account reference helps avoid delays.
4. Sign any authorisation form your new provider sends. This gives them permission to request your number from your old provider.
5. Do not cancel your old line until the port is confirmed complete.
6. Wait for the go-live date, then plug your handset in and test it by calling a mobile and asking someone to ring you back.

Matching account details to what your old provider holds is the single best way to keep the process running smoothly. Mismatched names or numbers are a common cause of delay.

How long it takes and what it costs

Porting a residential landline number is free. Your new provider will not charge to transfer it, and it is included in the standard switch process.

Timeframes vary depending on the providers and the type of service. Many residential ports complete within a few working days. As a broad guide, expect somewhere in the region of 5 to 14 working days, with full-fibre installations at the longer end if an engineer visit is needed. On the port date itself, the changeover usually takes a few hours rather than days. During that short window incoming callers might briefly hear a "number not recognised" message before everything returns to normal.

One cost worth flagging is separate from porting. If you are still mid-contract with your current provider, you may face an early exit fee for leaving before the term ends, typically your remaining monthly cost multiplied by the months left. The number transfer is free, but that exit fee can be significant, so check your contract end date before you switch.

Remember too that you will still pay the monthly cost of your new broadband and phone package. Call charges vary: some providers include UK calls or weekend calls with their broadband plans, while others charge extra for a calls package, often in the region of £5 to £10 a month for unlimited UK calls.

When you might not be able to keep your number

There are a few situations where keeping your number is not possible:

• Moving to a different area code. As above, geographic numbers are tied to their exchange, so moving out of the area usually means a new number.
• Switching to a provider that doesn't offer a landline. If your new service is broadband-only or mobile broadband with no phone service, there is nothing to port your number to. Check before you sign up.
• Cancelling your old line first. If the number has already been disconnected, it may no longer be portable. Keep the old service live until the transfer completes.

If you find yourself unable to keep your number, it is worth asking whether you still need a landline at all. Many households now rely entirely on mobiles. If your landline is mainly for receiving calls, updating your contacts and dropping the line can save on call charges and simplify your setup. If you need a landline for a specific reason, such as a telecare device or security alarm, check that the equipment is compatible with digital voice before switching, as some older devices need an adapter or replacement.

Frequently asked questions

Does the number transfer happen automatically or do I have to request it? You have to request it when you sign up with your new provider. Once you have, the transfer is handled automatically as part of the One Touch Switch process, so you don't need to contact your old provider yourself.

Does switching to VoIP or digital voice change my number? No. Moving to a digital landline or VoIP service does not change your number. In most cases your existing number can be ported straight across.

Can I port my number away again later? Yes. It is your number. You can move it to another provider whenever you switch again.

What if my broadband goes down, can people still reach my landline? Digital voice depends on your broadband and mains power, so it will not work in an outage or power cut. Most providers offer call diversion to a mobile so you don't lose access to the number, and Ofcom requires providers to offer a backup solution such as a battery unit for those who need it.