BT's 25 million fibre target slips to March 2027 — with 87 days left on the copper clock

5 November 2026. BT Group published its half-year results this morning, and buried in the operational detail is a date that matters to anyone still running a business line on copper: Openreach now expects to reach its 25 million-premises full-fibre build target in March 2027 — a slip from the previous December 2026 date. The footprint stands at 24.1 million premises after 1.2 million premises passed in the six-month period, with more than 10 million FTTP connections reached in October and take-up at 41%. Meanwhile the copper exit continues: 366,000 broadband lines were lost in the half (175,000 of them in Q2), with Openreach still expecting around 800,000 losses across the year.

Why a three-month slip matters when copper has a fixed end date

The fibre build and the PSTN closure are two different clocks — and only one of them moves. The PSTN closes on 31 January 2027: 87 days from today, and Openreach has been explicit that the date will not be delayed again. Openreach's own migration update last week put around one million lines still on legacy copper, including roughly 300,000 business premises — payment terminals, lift emergency phones, fire and security panels, door entry systems among them. If fibre arrives at a business's door in February rather than December, the analogue network does not wait: the migration path is an IP-based service over whatever connection exists, with migration offers running to the 31 January deadline and the last-resort eVAC service — at £35 to £38.60 a month wholesale from 1 February 2027 — as the expensive fallback for lines that run out of road.

The rest of the results, briefly

Group revenue came in at £8.8bn, up 1%, with reported profit before tax up 12% to £1.1bn and £312m of annualised cost savings delivered in the half as total labour resource fell 11% to 90,000. Business FTTP connections grew by 40,000 to around 0.4 million, and 5G+ population coverage rose to 81%. The results are also the first to book the TalkTalk rescue: BT acquired TalkTalk Telecommunications and PlatformX Communications out of administration on 5 October, protecting services for 2.5 million customers while the regulatory review runs its course. That deal is the reason thousands of small businesses are currently sitting on a provider whose ownership, systems and product roadmap are all in flux.

Do not wait for fibre to save your number

The lesson of a slipping build target is that infrastructure dates are estimates — but the deadline that governs your phone line is not. IP voice works over any working connection, so the number can move long before fibre does: a UK virtual number ports across and answers over SIP on mobiles, desk phones or a softphone, from free pay-as-you-go up to Pay Monthly at £9.97 a month. Resellers serving customers mid-migration can provision wholesale DID numbers independently of any single network owner. And where the line in question is an alarm panel rather than a phone, the job is different again — TAP-to-SMS signalling over IP keeps panel alerts flowing after the PSTN goes. The countdown and the deadlines are tracked in our PSTN switch-off guide.

Related: One million lines to go and the 6 November LOA deadline · BT buys TalkTalk and PXC out of administration · 16.4m premises now under copper stop-sell rules