2027 PSTN Switch-Off: What Every UK Estate Agent Must Do

Estate agents run on the phone. A buyer sees a listing, calls the branch, and if nobody answers, they call the next agent on the list. That makes the 2027 switch-off more than a background IT change for this sector.

On 31 January 2027, the old copper phone network across the UK shuts down for good. Every analogue line, every ISDN circuit, and a good deal of equipment quietly wired into them, from door entry systems to alarm panels, will need a digital replacement before that date.

UK estate agents must audit every branch phone line, alarm, and piece of line-dependent equipment now and move to a digital phone system, such as hosted VoIP, well before 31 January 2027, since Openreach will not extend the deadline. PurpleUC, a UK business telecoms and connectivity specialist, works with property firms on exactly this kind of migration, covering hosted VoIP, Microsoft Teams Phone integration, and backup connectivity for branches that cannot afford dropped calls. Its estate agents page sets out how that support fits agencies with multiple sites and managed properties.

Key Takeaways

• The UK’s old copper phone network closes on 31 January 2027, with no extension to the deadline.
• Estate agents need to check branch phones, alarms, door entry systems, and card machines at managed properties, not just the office switchboard.
• Moving to a digital phone system like hosted VoIP protects branch numbers and calls, but only if it’s tested and planned branch by branch.

What Changes by 31 January 2027?

By 31 January 2027, the Public Switched Telephone Network (PSTN), the copper-based system that has carried UK phone calls for over a century, closes permanently. Openreach, the network arm of BT Openreach, has confirmed this date with no planned extension.

Which Phone Services Are Being Retired?

Analogue phone lines and ISDN2 and ISDN30 circuits stop working on this date. Any phone system still connected to one of these will lose its dial tone unless it has moved to a digital alternative first.

Wholesale Line Rental (WLR), the product many providers use to supply analogue lines, is being wound down alongside them. This affects any office still billed for a traditional landline rental.

What Has the Stop-Sell Already Changed?

A national stop-sell has been in place since September 2023, meaning providers can no longer sell new analogue or ISDN lines. Existing lines are effectively frozen, so agencies cannot add new analogue extensions or move an old-style line to a different provider without upgrading it.

Openreach has also raised rental prices for WLR products in stages through 2026, roughly doubling the cost compared with a year earlier. Waiting is no longer the cheaper option.

Does the Deadline Mean Copper Broadband Ends Too?

The switch-off affects broadband as well as calls. ADSL and FTTC broadband both rely on the same copper network, so these connections stop working when PSTN closes, even though they carry internet traffic rather than voice calls.

Branches on FTTC will need to move to full fibre (FTTP) or SoGEA before the deadline, not just after their phone system changes. Read more about why the PSTN switch-off isn’t just about phone lines for a fuller picture of what’s affected.

Which Estate Agency Services Need an Audit?

An estate agency needs to check every line-connected device across its branches and managed properties, not just the phones on reception desks. Missing one line during the audit is the most common cause of disruption when the switch-off arrives.

Check Branch Numbers, PBX Connections and Fax Lines

Start with a full list of branch phone numbers, direct-dial lines, and any on-premise PBX system still running on ISDN. Fax machines, still used by some agencies for solicitor and mortgage paperwork, often sit on a forgotten analogue line.

Identify Alarms, Entry Systems and Equipment at Managed Properties

Door entry systems, intruder alarms, and fire alarms at branch offices frequently dial out over the same copper network. Managed rental properties may also have lift emergency phones or telecare devices connected to a landline, particularly in blocks with vulnerable tenants.

Card payment terminals and franking machines are easy to overlook because they sit in the back office rather than the shopfront. Anything that dials out for authorisation needs checking against this list.

Confirm Who Maintains Each Line-Dependent Device

Alarm systems and lift phones are usually maintained by a third-party contractor, not the agency itself. Contact each supplier to confirm what replacement they recommend and how long the changeover will take, since some devices need certified testing before they can go live on a digital line.

How Should an Agency Replace Its Phone System?

Most estate agencies will replace analogue lines and ISDN with a hosted VoIP system, which routes calls over the internet instead of copper cabling. The right setup depends on how many branches an agency runs and what phone system it already uses.

When Does Hosted VoIP Suit Multiple Branches?

Hosted VoIP suits agencies with several branches because it centralises call routing, voicemail, and number management in the cloud rather than in each office. A call to a branch number can ring a mobile or another branch automatically if nobody answers on-site, which matters when a valuer or negotiator is out viewing a property.

PurpleUC’s hosted VoIP is built around this kind of flexibility, letting branches share call handling without needing separate hardware at each site. See how cloud phone systems save you money for the cost side of that comparison.

Could Microsoft Teams Phone or SIP Trunking Fit an Existing Setup?

Agencies already using Microsoft Teams for internal communication can add Microsoft Teams Phone integration, turning Teams into the branch phone system without extra hardware on every desk. This suits firms that want calling built into the same tool their staff already use daily for messaging and video calls.

Agencies with a newer, IP-capable PBX might prefer SIP trunking or direct routing instead, keeping the existing system but replacing the underlying line. Both routes solve the same problem: getting off ISDN and analogue before 2027.

How Do You Keep Branch Numbers During Migration?

Branch numbers can usually be ported, or transferred, to the new digital service, so customers keep dialling the same number they’ve always used. Number porting takes planning and lead time with the provider, and it should be tested before the old line is cancelled, not assumed to work automatically.

What Connectivity and Backup Will Digital Calling Need?

Digital calling depends on a stable internet connection, so the choice of connectivity at each branch matters as much as the phone system itself. A hosted VoIP system is only as reliable as the broadband or fibre line carrying its calls.

Compare SoGEA, Full Fibre and Dedicated Connectivity

SoGEA delivers a broadband-only line without a traditional phone service riding on it, which suits smaller branches that only need internet and VoIP calling. Full fibre (FTTP) offers faster, more resilient connectivity where it’s available, and a dedicated leased line suits busier branches or head offices that can’t tolerate slow call quality during peak hours.

PurpleUC supplies fibre broadband, SoGEA, and leased lines as part of its connectivity range, so an agency can match each branch to the right option rather than fitting every site with the same product. Details sit alongside its internet and connectivity services.

Plan for Call Quality, Internet Outages and Power Cuts

An internet outage at a branch will take its phone system down with it unless there’s a backup in place. A 4G backup connection keeps calls working if the main broadband line drops, and it’s worth confirming this is included before migration rather than added afterwards.

Battery backup for the router and phone equipment protects against short power cuts, and it matters for any branch relying on emergency voice access for alarms or telecare devices nearby.

How Can You Migrate Without Missing Customer Calls?

Migrating without missing calls means planning each branch separately and testing before switching off the old line. A rushed, single-day cutover across every branch increases the risk of a missed call from a prospective buyer or tenant.

Set a Branch-by-Branch Plan With Your Providers

Work with the phone provider and connectivity provider together, since porting a number and installing new broadband are usually separate jobs with their own lead times. Ofcom’s guidance on the switch-off recommends starting this early precisely because fibre installs and number porting can take weeks, not days.

Stagger the migration across branches rather than moving every site on the same date. This keeps at least some branches unaffected if an issue comes up during one office’s changeover.

Test Calls and Safety-Critical Devices Before Cancelling Old Lines

Test inbound and outbound calls on the new system before cancelling the old PSTN line, including calls diverted out of hours. Any lift emergency phone or telecare alarm connected at a managed property needs its own separate test and sign-off from the equipment’s maintainer, since a working phone line doesn’t guarantee a working alarm signal.

Keep the old line active until every test has passed. Cancelling early to save a month’s rental isn’t worth the risk of a branch going silent during a busy viewing weekend.

Keep Every Branch Reachable Beyond the Deadline

Every UK estate agency branch needs a working phone number after 31 January 2027, and that means starting the audit and migration now rather than waiting for the deadline to arrive. Cloud telephony gives agencies the flexibility to route calls between branches, staff mobiles, and out-of-hours cover in ways the old copper network never could.

The agencies that manage this well treat it as a full estate review, covering branch phones, alarms, door entry, and managed-property equipment together. That approach protects customer calls and avoids the kind of last-minute scramble many UK businesses are still facing as the deadline gets closer.

PurpleUC’s work with estate agents focuses on this kind of branch-by-branch planning, pairing hosted VoIP and Microsoft Teams Phone integration with the right connectivity and backup for each site.

Frequently Asked Questions

Are estate agency landlines being switched off in 2027?

Yes, all analogue landlines and ISDN lines across the UK are being switched off on 31 January 2027. This includes branch office landlines, so any agency still using a traditional phone line needs a digital replacement in place before that date.

Will our branch phone numbers change when we move to VoIP?

Branch numbers can usually be kept through a process called number porting, which transfers the number to the new digital service. This needs to be arranged with the provider in advance and tested before the old line is cancelled, since it isn’t automatic.

Will FTTC broadband still work after the PSTN switch-off?

No, FTTC broadband relies on the same copper network as ISDN and analogue phone lines, so it stops working when PSTN closes. Branches on FTTC need to move to full fibre or SoGEA before the deadline to keep their internet and VoIP calling running.

How much will it cost an estate agency to move to digital calling?

Costs vary by branch count, existing equipment, and connectivity needs, so there’s no single figure that applies to every agency. Openreach’s rental price rises on legacy lines through 2026 mean that delaying migration is now more expensive than moving early in many cases.

What happens to calls during a broadband or power outage?

Calls stop working if the branch’s internet connection or power goes down, unless a backup is in place. A 4G backup connection and battery backup for phone equipment reduce this risk and are worth confirming as part of any migration plan.