Openreach rules out extension as January 2027 PSTN deadline nears

Openreach has told communications providers in writing that the January 2027 deadline for switching off the UK's Public Switched Telephone Network (PSTN) will not move, and that thousands of businesses and households still on traditional landlines risk losing service if they do not migrate in time.

The warning came in an urgent letter to providers, in which the network operator closed off any hope of a reprieve. "This letter serves as confirmation that the January 2027 deadline will not be moved," the letter states.

The stakes for laggards are concrete. Customers who miss the deadline face one of two outcomes: their phone services could be cut off, or they could be automatically moved onto Emergency Voice Access (EVAc), a temporary service that provides basic voice calls only. Openreach was blunt about the limits of that fallback.

"While EVAc will provide a temporary safeguarding service for basic voice connections, it is not built to support the connectivity needs of a modern business," the letter adds.

What happens to businesses that delay?

Two costs follow from ending up on the temporary service. Moving customers from EVAc onto a permanent digital connection is likely to mean extra charges and avoidable downtime. And as the deadline approaches, engineering appointments will become harder to secure, squeezing businesses that leave the switch until the last minute.

Openreach set out the risk plainly: "Businesses that delay the move risk significant disruption, operational challenges and significant unnecessary costs. And with the industry entering the final phase of migration, waiting too long could also make it harder to secure the engineering support needed before the deadline."

The operator is urging providers to contact customers still using older phone services and get them switched over before time runs out. The migration effort itself is not new — Openreach has been running a public campaign to push customers onto digital alternatives for years, and this letter marks the shift into what it calls the final phase.

How much more are legacy lines costing?

The financial pressure on holdouts is already biting. Wholesale price increases introduced on 1 October 2026 have roughly doubled the rental cost of traditional lines compared with 2025 — an effective doubling in the space of about a year for any customer still sitting on copper-era services. A further increase is due on 1 February.

That escalation gives providers a commercial reason to act alongside the regulatory one: the longer a customer stays on the old network, the more the service costs the reseller and, in most cases, the end user.

The price stick and the hard deadline together form the backdrop to the letter's closing appeal. "The January 2027 deadline is approaching. Every delayed migration increases risk, complexity, and avoidable cost. However, every customer migrated today means one less organisation left exposed to this," the letter concludes.

"Time is running out – the PSTN migration is now a critical priority. The window for a managed and orderly transition is closing, and providers who haven't already taken action need to immediately do so to mitigate risk and protect their customers."

Is the message landing?

The letter's tone suggests Openreach believes it is not, at least not fast enough. Thousands of lines remain on the legacy network with little more than a year to go, and the operator is now pushing the responsibility for customer contact squarely onto communications providers rather than carrying the migration message itself.

What the letter does not do is quantify the remaining base — no figure for how many lines are still to migrate appears in it, which makes the pace of the final phase difficult to judge independently. The next visible markers are the 1 February price increase and the shrinking pool of engineering slots as January 2027 approaches.