PSTN Switch Off UK: The Complete Business Migration Checklist
PSTN switch off UK business owners keep asking the same question. What must we do before January 2027?
Your phone system is more than wires. It is the first welcome, the start of a new chance, the link that holds your team and customers together. The PSTN switch off is not only a technical change. It is a moment to design something better. A chance to shape how your business connects and communicates.
At Cleartwo, we help UK organisations make this move smooth and thoughtful. As a managed UK VoIP specialist, we handle setup, number porting, Teams phone integration, and support. With enterprise grade features at SME prices and a 99.99 percent uptime SLA, the whole journey feels calm and clear.
What The PSTN Switch Off UK Business Deadline Means
The Public Switched Telephone Network is the old copper system behind UK landlines. By 31 January 2027, it will be turned off for good.
If your business still uses analogue lines or ISDN, those services will stop. No dial tone. No backup.
This affects many parts of your setup:
- Office landlines
- ISDN systems
- Fax machines
- Alarm lines
- Lift emergency phones
- Some EPOS units
- Old broadband services
The future is fully digital. Calls will travel over the internet using hosted VoIP, cloud PBX, or SIP trunking.
To see this technology explained simply, explore our VoIP guide.
Map Your Communications Before The PSTN Switch Off UK Deadline
Upgrading a phone system without checking your alarms or lift lines can cause chaos. Many businesses focus only on handsets and forget the wider picture.
Start by mapping every part of your communications setup to see what you have before you design what comes next.
- List every phone line and number.
- Note which lines are PSTN, ISDN, or SIP.
- Check devices like alarms, lifts, or EPOS.
- Test broadband speed and reliability.
- Record contract end dates.
Clarity at this stage leads to better choices. If this feels heavy, the Cleartwo team can carry out a full audit.
Reimagine Your Business Telephony UK Setup
This switch is not simple replacement. It is redesign.
Think about the experience you want callers to feel. Modern VoIP systems offer tools that shape a smoother story:
- Auto attendants to greet callers
- Call recording for safety and quality
- CRM links that keep customer details clear
- Softphones for mobile teams
- Video meetings that feel natural
- Live analytics for smart choices
- Teams phone integration for one simple space
For teams already on Microsoft 365, a Teams phone system feels seamless.
Others may prefer a VoIP phone system for more freedom. Every detail shapes how your brand is felt.
Upgrade Connectivity And Resilience
VoIP depends on strong internet. Your connection is now part of your story.
Most small to medium businesses need 100 Mbps or more. Larger sites may need 250 Mbps.
Think about resilience too:
- Fibre as the main line
- 4G or 5G as backup
- Power backup for routers
- Automatic call failover
Cleartwo blends VoIP with managed IT support so voice and data work in harmony.
Plan Number Porting And SIP Trunking Early
Your numbers are part of your brand. They appear everywhere and hold history. You can keep them through number porting.
Simple ports take around ten working days. Complex ones take longer, so plan ahead.
SIP trunking suits businesses with on site PBX systems. Cloud PBX suits fully online setups.
To compare options, see our comparison guide.
Understand Compliance And Call Recording
Some sectors need call recording for compliance. VoIP systems offer encrypted storage and easy access.
Recordings can also link with CRM tools for smoother journeys. Learn more in our CRM integrations guide.
Choose A Strong Migration Partner
Providers differ. Some leave you to set up alone. Others guide you with care.
Cleartwo partners with CallSwitch One to offer strong cloud voice tools with UK support.
With Cleartwo you get setup, training, and ongoing tuning. The result is simple:
- Fast rollout
- Clear pricing
- UK based support
- Strong features
- Easy scaling
- Proactive monitoring
You are not buying a product. You are shaping an experience that grows with you.
Beyond Telephony: A Path To Digital Growth
The PSTN switch off often sparks bigger ideas. How connected is your business? How smooth is your customer journey?
Your VoIP system can link with:
- Custom CRM systems
- AI marketing tools
- E commerce systems
- Web design services
- IT security tools
Explore our insight on connected systems at this link.
For wider support, read our guide on outsourcing IT support.
Your PSTN Migration Checklist
Here is your full list:
- Map all lines.
- Check connected devices.
- Review broadband.
- Choose key features.
- Pick VoIP or SIP.
- Start number porting early.
- Test backups and failover.
- Train your team.
- Monitor and refine.
This is not just a required change. It is a chance to design something better.
Cleartwo is ready to help you shape that next chapter.







