Quick summary: BT Openreach is permanently switching off the PSTN and ISDN network on 31 January 2027. Every Belfast and Northern Ireland business still on a traditional landline or ISDN line will lose their phone service on that date unless they migrate to a VoIP or IP-based system beforehand. This is not optional and it is not a gradual phase-out — it is a hard deadline. Dromlik, a cloud phone system serving the entire island of Ireland, provides Belfast businesses with local +44 28 numbers, a fully managed migration from PSTN/ISDN to cloud VoIP, GBP billing, and direct support throughout the switchover. Plans start from €12/user/month (annual). The deadline is January 2027 — the time to act is now.
What Is the PSTN Switch Off?
By 31 January 2027, BT Openreach will permanently switch off the Public Switched Telephone Network (PSTN), the Integrated Services Digital Network (ISDN), and ADSL services. These are the analogue copper-based phone networks that have served UK businesses for decades.
As of 5 September 2023, BT Openreach initiated a national stop-sell for both PSTN and ISDN — meaning no new PSTN or ISDN services can be purchased or modified. If your Belfast business is still on one of these networks, you can continue using it until the switch-off date — but you cannot add new lines, and the service will cease entirely on 31 January 2027.
All ISDN30 (PRI), ISDN2e (BRI), and analogue phone lines across the UK will be permanently decommissioned by January 2027. This is not a regional pilot or a gradual phase-out — it is a complete, irreversible shutdown of the entire copper telephone infrastructure.
BT Openreach has confirmed the switch-off date is final. Belfast businesses still on PSTN or ISDN lines must migrate to an IP-based phone system before this date or lose their phone service entirely.
What Happens If You Don’t Migrate?
Some services, including ISDN, Featureline, multiline and certain broadband accesses cannot be moved automatically with BT’s Protective Migrations programme. These services will stop working from 31 January 2027 if you do not move them to an IP technology solution.
For a Belfast business, this means:
- Your existing landline number stops working entirely
- Any phone system connected to an ISDN line ceases to function
- Call routing, IVR, and any business process built on your existing line is interrupted
- Customers dialling your established business number reach nothing
Traditional phone lines aren’t just for making voice calls — various products and services that use these lines, such as alarms, EPOS machines, door entry systems, CCTV, and fax machines, may also be affected. If any of these systems in your Belfast premises connect via a PSTN line, they need to be assessed and potentially migrated separately.
Why Belfast Businesses Need to Act Now
Too often, the switch-off is viewed as a straightforward telecommunications upgrade when, in reality, it represents a significant business resilience challenge.
The reason to migrate now rather than in December 2026:
Number porting takes time. Migrating your existing +44 28 Belfast number to a new system takes 5–10 business days minimum. If you wait until the last moment and encounter a porting complication, your number may be unserviceable on switch-off day with no fallback.
The migration queue will fill up. Thousands of Northern Ireland businesses are in the same position. Telecoms providers’ migration capacity is finite — the closer to January 2027, the longer the wait.
Your team needs time to adapt. Moving from a desk-phone-based PSTN system to a cloud VoIP setup involves your team learning new apps and workflows. Doing this at the last minute, under pressure, creates disruption. Doing it now gives your team months to adapt comfortably.
Testing takes time. A migration that goes live two weeks before the deadline with no time to troubleshoot is a risk. A migration completed six months ahead of schedule can be tested thoroughly, with the old system still running as backup.
BT’s own guidance recommends businesses upgrade well before the January 2027 deadline. The process of assessing systems, migrating numbers, and training staff requires time that compresses dangerously if left until the last quarter of 2026.
Why Belfast Businesses Choose Dromlik for Their PSTN Migration
Dromlik serves the entire island of Ireland — including Belfast and across Northern Ireland. For a Belfast business migrating away from PSTN, Dromlik provides:
Local +44 28 Belfast numbers. Your existing Belfast number ports across free of charge. Customers continue dialling the same number — nothing changes on their end. New +44 28 numbers are available immediately if needed.
Fully managed migration. The Dromlik team handles the migration from PSTN to cloud VoIP end-to-end — number porting, system configuration, routing rules, IVR setup, and staff onboarding. Your Belfast business doesn’t need a telephony engineer or an IT project to make this transition.
No hardware required. Your team takes calls on the Dromlik app on their existing mobiles, laptops, and desktops. No new desk phones required (though Yealink IP phones are available if preferred). The migration doesn’t involve any new equipment arriving at your premises.
GBP billing available. Belfast customers are billed in sterling. Call the team on +44 28 9552 1120 for GBP pricing specific to your setup.
Cross-border capability. For Belfast businesses with customers, suppliers, or staff in the Republic — or companies operating across the border — Dromlik handles calls across the island seamlessly. Irish Republic numbers (01, 021, 091 etc.) can be added alongside your +44 28 number.
AI receptionist for after-hours and overflow. Niamh, Dromlik’s AI receptionist, answers calls when your team can’t — during busy periods, after hours, or when everyone is occupied. For Belfast businesses using PSTN who have never had this capability, switching to cloud VoIP is also an opportunity to add AI call handling at a fraction of the cost of a human receptionist.
What You’re Migrating From and To
| PSTN / ISDN | Dromlik Cloud VoIP | |
|---|---|---|
| Infrastructure | Copper lines, on-premise hardware | Cloud-hosted, no premises hardware |
| Switch-off date | 31 January 2027 | N/A — cloud-based, no switch-off |
| Belfast +44 28 numbers | ✓ | ✓ (ported across free) |
| Mobile working | ✗ | ✓ App on any device |
| Adding new users | Engineer visit + new line | Minutes, from dashboard |
| Call recording | Rarely included | ✓ Included |
| AI receptionist | ✗ | ✓ Add-on |
| After-hours routing | Basic | ✓ Configurable |
| CRM integration | ✗ | ✓ (Orbit plan) |
| Cost | Varies + maintenance | From €12/user/month (annual) |
What the Migration Looks Like
For a typical Belfast SMB migrating from PSTN to Dromlik:
Step 1: Assessment (Day 1–3) Dromlik’s team reviews your current setup — how many lines, what numbers, what equipment, what services (alarms, EPOS, fax) might also be affected. Any non-phone PSTN-dependent services are flagged separately.
Step 2: Configuration (Day 3–7) Your Dromlik system is configured — call routing, IVR, business hours rules, greetings, and integrations. Your team receives access to the app.
Step 3: Number porting (Day 7–17) Your existing +44 28 Belfast number is submitted for porting. This typically takes 5–10 business days. Your PSTN line keeps working throughout — there is no gap in service.
Step 4: Go live On porting completion, your number routes through Dromlik. The PSTN line is no longer needed. Your team makes and receives calls through the app, on existing devices.
Step 5: PSTN line cancellation Once porting is confirmed and everything is working, you cancel your PSTN/ISDN contract. Well ahead of January 2027.
What About Other PSTN-Dependent Systems?
Various products and services use traditional phone lines, such as alarms, EPOS machines, door entry systems, CCTV, and fax machines. If your Belfast premises has any of these:
- Alarm systems — many older alarm panels use PSTN to communicate with monitoring centres. Contact your alarm provider to confirm whether your system needs upgrading.
- EPOS and payment terminals — many older card terminals used PSTN for transaction processing. Most modern terminals use broadband or mobile data — check with your terminal provider.
- Door entry and intercom systems — some older systems use PSTN lines. Confirm with your installer.
- Fax machines — fax can be migrated to a cloud fax service that works over broadband. If fax is business-critical, speak to Dromlik’s team about options.
These systems are outside Dromlik’s scope but need to be assessed as part of your overall PSTN migration. The Dromlik team can advise on what to check and who to contact.
Pricing
Belfast customers are billed in GBP — contact the team on +44 28 9552 1120 for GBP pricing. EUR reference pricing:
| Plan | Monthly | Annual | What’s Included |
|---|---|---|---|
| Nucleus | €15/user/month | €12/user/month | Calling, IVR, routing, call recording, voicemail to email, mobile and desktop apps, Teams integration |
| Orbit | €27/user/month | €22/user/month | Everything in Nucleus plus omnichannel (WhatsApp, SMS, chat), CRM integrations, call centre queues, AI transcription |
| AI Receptionist (Niamh) | +€100/month system-wide | +€100/month system-wide | 24/7 AI call answering, 200 minutes included |
+44 28 Belfast numbers from €5/month. Free number porting. No setup fees. 7-day free trial.
Migrate your Belfast business away from PSTN before January 2027
Call Dromlik’s Belfast line on +44 28 9552 1120 or book a demo online. Free 7-day trial, no setup fees, managed migration from PSTN to cloud VoIP.
