Question 1

What is the PSTN switch-off?

Accepted Answer

The PSTN (Public Switched Telephone Network) switch-off is the UK's planned retirement of the traditional analogue telephone network. By January 2027, all services running over the copper phone network - including landlines, ISDN, and some broadband connections - will be discontinued and replaced with digital alternatives.

Question 2

Why is the PSTN being switched off?

Accepted Answer

The copper telephone network is over 40 years old and becoming increasingly expensive to maintain. Digital technology offers better reliability, more features, and lower running costs. The switch-off is part of a nationwide infrastructure upgrade to future-proof UK communications.

Question 3

When exactly will the switch-off happen?

Accepted Answer

The full switch-off is scheduled for 31 January 2027. However, Openreach began a national 'stop sell' of new PSTN products from late 2025, meaning you may need to migrate sooner if moving premises or adding new lines.

Question 4

Is this happening across the whole UK?

Accepted Answer

Yes, the switch-off affects the entire UK. All major network operators are migrating to digital infrastructure. The timeline may vary slightly by region, but by 2027 all traditional phone services will end.

Question 5

What happens if I don't migrate before 2027?

Accepted Answer

If you haven't migrated by the deadline, your traditional phone lines will stop working. You'll be unable to make or receive calls until you upgrade to a digital alternative. We strongly recommend migrating well before the deadline to avoid disruption.

Question 6

Will my phone number change?

Accepted Answer

No, you can keep your existing phone numbers. Number porting is a standard process that transfers your numbers to your new digital service. We handle this for you at no extra cost.

Question 7

What about my broadband?

Accepted Answer

If your broadband uses a traditional phone line (ADSL), you'll need to upgrade to a line-independent service like SoGEA, FTTP, or a leased line. If you already have fibre (FTTC or FTTP), your broadband service itself won't be affected, but the voice line portion will need to change.

Question 8

What devices might be affected?

Accepted Answer

Beyond phones, several devices often connect via phone lines: burglar and fire alarms, EPOS/card payment terminals, lift emergency phones, fax machines, franking machines, and telecare/pendant alarms. These all need assessing for compatibility with VoIP.

Question 9

What are my options for replacing phone lines?

Accepted Answer

There are three main paths: 1) Cloud Communications (SelectVoice) - a complete cloud phone system replacement; 2) SIP Trunking - keeps your existing PBX but connects it digitally; 3) Teams Voice / Direct Routing - adds calling to Microsoft Teams if you use Microsoft 365. The right choice depends on your current setup and needs.

Question 10

What if I have a PBX system I want to keep?

Accepted Answer

SIP Trunking is designed for this scenario. It replaces your ISDN lines with a digital connection while keeping your PBX hardware. You'll need to check your PBX supports SIP - most modern systems do, and many older systems can be upgraded.

Question 11

We use Microsoft Teams - what should we do?

Accepted Answer

Teams Voice with Direct Routing is likely your best option. It adds full phone system capabilities to Teams, letting you make and receive calls using your business numbers directly within the app. Telappliant provides the numbers, calling plans and SBC infrastructure.

Question 12

Can I make the switch gradually?

Accepted Answer

Yes, phased migration is possible. For example, you could move your main office first, then branch sites. Or migrate phones first while keeping alarm lines temporarily. We'll work with you to plan a transition that minimises disruption.

Question 13

How much will migration cost?

Accepted Answer

Costs vary depending on your chosen solution and complexity. VoIP typically has lower ongoing costs than ISDN. We provide free, no-obligation assessments with clear pricing. Many businesses find their monthly costs decrease after migration.

Question 14

How long does migration take?

Accepted Answer

Most migrations can be completed within 2-4 weeks. Simple setups may be faster; complex multi-site migrations may take longer. Number porting typically takes 5-10 working days. We recommend starting the process at least 3 months before you need to switch.

Question 15

Will I need new hardware?

Accepted Answer

It depends on your solution. With Cloud Communications, you may need IP phones or can use softphone apps on existing computers and mobiles. SIP Trunking typically works with your existing PBX handsets. Teams Voice works on any device with Teams installed.

Question 16

What support do you provide?

Accepted Answer

We provide end-to-end support: assessment, planning, number porting, installation, staff training, and ongoing technical support. For Cloud Communications and SIP Trunking customers, we offer UK-based engineer support.

PSTN Switch-Off FAQ

About the Switch-Off

Business Impact

Solutions & Options

Cost & Process

About the Switch-Off

Business Impact

Solutions & Options

Cost & Process

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