A UK business still on traditional phone lines has until 31 January 2027, when Openreach says the Public Switched Telephone Network (PSTN) is permanently decommissioned. The safe plan is to list everything attached to your lines, pick an internet-based voice route for each, and get a written migration date for every service. Openreach's own emergency fallback is limited, so treat it as a safety net and not as an extension.
What happens on 31 January 2027?
On 30 October 2026 Openreach warned that only three months remain until the permanent decommissioning of the PSTN on 31 January 2027. It says about one million copper-based lines are still active across the UK, including 300,000 in business premises.
The change affects ISDN as well as ordinary analogue lines. Calls move onto an internet connection using technology called VoIP, Digital Voice or All-IP. Your internal extensions can carry on working, but the connection that carries your calls to the outside world has to change.
Openreach also says its final announced rental rise for the WLR basic product, other WLR variants and legacy ISDN services took effect on 1 October 2026, doubling the 2025 rental price for legacy lines. That is a wholesale cost to phone providers, so your own bill may not double, but it is another reason not to wait.
Which devices on your lines need checking before the switch-off?
Government guidance is clear that landlines may also be used for lift alarms, burglar alarms or card payment systems and that your phone provider will not know which devices are connected. You have to find them yourself.
The same guidance lists alarm systems, telecare devices and fax machines among the equipment that may need an upgrade, its own battery and network back-up, or an adaptor. If you are buying a new alarm or device, it says to check that it works with VoIP services or can connect through a mobile service such as 4G.
Openreach adds building access controls, automated gates, door entry units, industrial telemetry and building energy management systems to its list of services that still rely on the PSTN. It names multi-site organisations with several suppliers and undocumented circuits as the hardest to migrate.
A simple register does the job. For each line, record the site, the number, what it is used for, the device on it, who maintains that device and who signs off the replacement. Then ask each maintainer, in writing, what they will support.
Do you need full fibre, or is SoGEA enough?
You do not need to remove every copper cable or buy full fibre to meet the deadline. The thing that ends is the traditional voice service. Your voice can run over broadband that you already have, as long as it has enough bandwidth.
BT says its Cloud Voice can be supported on any connection with sufficient bandwidth, while recommending its own leased line or business fibre broadband so that one supplier looks after the whole service. That is a sensible trade. A single supplier means one party to call when call quality drops, which is worth weighing against the cheapest quote.
If you buy voice and broadband from different suppliers, agree in advance who investigates faults. A voice service is only as steady as the connection under it.
What does a replacement phone service cost?
BT publishes prices for its Digital Voice for Business plans. The Essential plan costs £15 per user per month, Enhanced £18 and Extra £21, all excluding VAT. The same page says the monthly price rises by £1 each 1 April, so Essential becomes £16 on 1 April 2027 and £17 on 1 April 2028.
BT Digital Voice for Business price per user rises each April
Published monthly price per user for the Essential plan, excluding VAT, in 2026, 2027 and 2028
View the data
| Category | £ per user per month excluding VAT |
|---|---|
| Essential 2026 | £15.00 |
| Essential 2027 | £16.00 |
| Essential 2028 | £17.00 |
BT Cloud Voice is priced differently. Its Basic licence is shown at £10.52 a month on a 60-month licence, rising by £1 each 1 April. Calling charges are separate, so ask for a full quote before comparing it with a per-user plan. Prices were checked on 1 November 2026 and may change, so confirm them on BT's site before you order.
A fair budget covers more than licences. Include broadband or a leased line, handsets or adaptors, number porting, installation, training, a back-up connection and any overlap while the old service runs down. Ask each bidder to mark every item as included, chargeable or not needed.
How should you plan the migration?
A workable order is discovery first, then a pilot site, then the remaining sites in waves, then acceptance testing, then ongoing support. Treat any specialist device as its own mini project with its own owner.
Appoint one owner on your side and one on the supplier's. Call a site finished when the business services have been tested and signed off, not when the new handsets turn on. Do not cancel the old lines until number transfer and the replacement service are confirmed in writing.
Ask any provider where its technical support is based and what response times it commits to in the contract. BT states a 24/7 UK-based helpdesk for Cloud Voice, but you should put the same question to every bidder and get the answer in the order form.
What is the safety net if you miss the date?
Openreach says from 31 January 2027, customers who have not moved to a modern digital service may be transferred to its Emergency Voice and Access Continuity service, EVAc, a limited last-resort service for essential calls. Where technically possible it will also keep linked broadband running. It costs communications providers £35 a month for WLR3 Basic and £38.60 for WLR Premium, and Openreach describes it as temporary, limited and more expensive than modern digital alternatives.
These are wholesale prices paid by providers, not what you would be charged. Because it is limited and designed as a final safety net, build your plan around finishing early.
Power cuts need their own plan. A VoIP phone needs powered equipment and a working connection, so a battery in the router alone does not keep the whole path alive. Ask each supplier what keeps working in a power cut, and keep a charged mobile phone for emergency calls.
What should you do this week?
- Pull the last three phone bills and list every line and number.
- Walk each site and note every device on a phone line.
- Contact alarm, lift, payment and telecare suppliers for their replacement route.
- Request written migration dates and a full cost list from at least two providers.
- Name a migration owner and book your pilot site.
Sources
- Openreach, Openreach warns businesses, fewer than 100 days left, 30 October 2026
- Openreach, Openreach to protect broadband connections as PSTN closure approaches, 2026
- GOV.UK, UK transition from analogue to digital landlines
- BT Business, Digital Voice for Business, checked 1 November 2026
- BT Business, BT Cloud Voice, checked 1 November 2026
