For most businesses the answer is yes. Your number is on your website, your vans, your invoices and your customers’ phones, and losing it would cost real money. The good news is that the UK has an established system for moving numbers between providers.
The process is mostly smooth when planned and messy when rushed. This article explains how it works and how to avoid the common problems.
What Number Porting Means
Number porting is the process of moving a phone number from one provider to another while keeping the number the same. When it completes, calls to that number start reaching your new service instead of your old one.
It applies whether you’re moving to a SIP trunk provider, a cloud PBX or a Teams voice setup. Because the old ISDN and analogue network is being retired, with Openreach setting 31 January 2027, a lot of UK businesses are porting numbers at the same time, which makes planning more important.
Which Numbers Can Usually Be Ported?
Most UK business numbers can be moved, though conditions differ by type.
Geographic numbers (01 and 02). Generally portable between providers. Portability to a different area is more limited, so ask about your specific numbers.
Non-geographic numbers (03, 08). Often portable too, though the provider who holds them and the service they’re attached to can complicate matters.
Direct dial ranges (DDI blocks). Commonly ported as a group so extensions keep working.
Always confirm the details for your specific numbers with the new provider before you commit, since each situation is different.
How the Process Works
The exact steps vary by provider, but the pattern is similar.
- Choose your new provider and confirm they can port your numbers.
- Provide authorisation. You’ll usually need to supply account details and sign a letter of authority, showing you’re entitled to move the numbers.
- The new provider submits the request to your current provider.
- A transfer date is agreed. It depends on the numbers involved and the checks required.
- Numbers move on the day. Calls begin arriving on the new service.
- You test and confirm that inbound and outbound calls work as expected.
The new provider usually leads the process, which is one reason to pick a supplier that manages it for you rather than leaving it to you.
How Long Does It Take?
There’s no single figure. Simple single-number ports can complete faster than large ranges or multi-site moves, and timelines can lengthen if information is missing or the old provider is slow to respond.
As a planning approach, start the conversation weeks before you need the numbers to move, and ask your new provider for a realistic date based on your specific numbers. Lead times may stretch as the January 2027 deadline approaches, so earlier is safer.
What Causes Delays
Most delays have ordinary causes.
Mismatched account details. The name, address or account number on the request doesn’t match what your old provider holds.
Missing authorisation. The letter of authority is unsigned or incomplete.
Unclear ownership. Numbers were set up years ago under a previous company name or by a past employee.
Contract complications. Early termination terms with your old provider may need resolving first.
Bundled lines and broadband. Cancelling a phone line can affect a broadband service that runs over it, so check before anything is cancelled.
Gather your latest bill and a list of every number before you start. It saves days.
How to Avoid Losing Calls on Cutover Day
A staged approach reduces risk.
Move a test number first. Port a single, low-risk number to confirm that routing and call quality work.
Prepare call routing before the move. Set up your new service so calls land correctly the moment numbers arrive.
Schedule outside peak hours where your provider can, and make sure staff know when the changeover happens.
Keep a fallback. Ask whether your old service can remain live briefly, and have a diversion plan if anything goes wrong.
Test straight afterwards. Call each key number from a mobile and a landline, and check inbound and outbound calls.
Examples for UK Businesses
A six-person plumbing firm has one main number on its vans. It ports that number first as a test, then moves its second line a week later.
A 25-person solicitors’ practice has a block of direct dial numbers. It ports the whole range together so every extension keeps its direct line.
A retailer with a freephone-style number finds it was registered years ago under a former trading name. Sorting out ownership before porting saves a delay at the critical moment.
Where Wavetel Business Fits In
When comparing suppliers, such as Wavetel Business, ask who handles porting and what support you get on cutover day. A provider that manages the process end to end takes a lot of the pressure off, especially when your numbers matter to your sales.
Frequently Asked Questions
Can I keep my business landline number when I move to VoIP?
In most cases, yes. Geographic numbers can generally be ported to a new provider, though it’s worth confirming for your specific numbers.
Will there be downtime when my number moves?
A well-planned port should involve little or none. Preparing routing in advance and testing a number first reduces the risk.
Do I need to tell my old provider I’m leaving?
Your new provider usually submits the port request, but checks your contract for notice periods and avoids cancelling lines before the port completes.
What if I can’t port my number?
Ask your provider about alternatives, such as forwarding the old number to the new service for a time, or issuing a new number while you update your materials.
Conclusion
Keeping your business number is usually possible, and doing it well is mostly a matter of preparation. Collect your account details, confirm ownership, choose a provider who manages the port, and move a test number first.
Your practical next step is to list every number you hold, who they’re registered with and what they’re attached to. Take that list to your shortlisted providers, and ask for a written porting plan and date.
