Three ways to find your date
Your line provider is the only source that knows exactly when your own lines will move. Use all three of these and go with the earliest date you find.
- Ask your provider in writing. List every line and number, and ask for the planned migration date of each.
- Check your post and email. Providers should contact you before moving you; look for words such as "digital voice" or "PSTN withdrawal".
- Use an official checker. Openreach and major providers publish exchange or postcode information. Check you're on the provider's or Openreach's real website.
Plan around your date
Choose where you stand, and see what to do first.
Openreach closes the PSTN on 31 January 2027. Lines that haven't moved may be transferred to EVAc, a limited last-resort service for essential calls. It can't be ordered in advance and isn't a plan for a business. Source: Openreach ↗ EVAc carries voice calls only, and published information conflicts on whether ISDN lines qualify, so don't count on it for ISDN, alarm or lift lines. Ask your provider.
Ask your provider for a written date per line, and ask for a full list of what you pay for. While you wait, start the dependency checker: finding what's on your lines takes longer than you might expect.
Contact the suppliers of lifts, alarms and other safety equipment this week. Confirm your phone system can use SIP or another digital service. Agree a porting plan for every number, and check your internet connection. If it's tight, ask your provider about timing. See Escalate safely: when to stop and call an engineer.
The Openreach date may not apply to you. In Hull and some nearby areas KCOM runs the network and has its own plans, and a few other networks do too. Ask for a written date, then work through the dependency checker.
Test day and night routing, every number, and anything that used the old lines: alarms, lifts, door entry and card machines. Keep the results with your fault log. If calls break up or drop, see Calls dropping after a few minutes.
Business and home lines are handled differently
Most public information about postcode checkers and BT Digital Voice is aimed at home phones, so business customers should confirm with their own provider. Business ISDN, multi-line services and lines connected to a phone system follow their own plans and need more preparation. Don't assume a home checker's date applies to your office lines.
Beware of pressure selling
The switch-off is real, but it isn't a reason to sign the first contract you're offered. Be cautious if someone says your phones will stop next month without giving a date from your own provider. Ask for the date in writing, and compare at least two options. Our decision guide sets out what to compare.
What to have ready before the move
| Item | Why |
|---|---|
| List of every line and number | Anything missed can stop working |
| What each line is used for | Lifts and alarms need their own plan |
| Phone system make and version | Decides whether it can use SIP |
| Internet connection details | Must carry your peak calls |
| A plan for outages | Digital lines depend on power and internet |
For the full picture, see ISDN switch-off: what it means for your on-site phone system. If you'd like someone to look over your plan, request a fault review.
Has the switch-off been delayed?
The original December 2025 target was moved, and the old network closes on 31 January 2027. A later national date doesn't protect your own lines: providers move customers in stages, and some exchanges go earlier. Plan from your own provider's date, not the national one.
Common questions
How do I check when my area switches off the PSTN?
Ask your line provider first, then check Openreach and major providers' official information. Business lines may differ from what a home checker shows.
Is there a landline switch-off postcode checker?
Providers and Openreach publish postcode or exchange information. Use their own websites, and confirm the result with your provider.
Will I be told before my line is switched?
Providers should contact you first, so check letters and emails. Don't wait for one if you have lifts, alarms or a phone system to plan for.
What happens if I do nothing?
Your lines will eventually be withdrawn, and ISDN won't move automatically. Alarms and other devices on those lines could stop working, and an on-site phone system loses outside calls until it's connected another way.
Is someone calling about the switch-off a scam?
Not always, but be cautious. Ask for the date in writing and check with your own provider before you sign anything.
Has the PSTN switch-off been delayed?
The original target of December 2025 was moved, and the old network closes on 31 January 2027. Your own line may move earlier, so check with your provider.
Where can I find ISDN disconnection dates?
Ask your provider for a written date for each line. Openreach publishes programme and exchange information, but your provider confirms what applies to you.
Sources
Last checked 9 November 2026 against the sources listed here. Menus and defaults can differ by software release, so confirm them on your own system. Spotted a mistake? Tell us.
