The rule
UK providers are required to support number portability. You can take a geographic number — an 0113, 0161, 020 and so on — from one provider to another, and your current provider cannot refuse simply because they'd rather keep you.
The number moves with the business, not with the line. You do not need to keep the old broadband, the old handsets or the old contract to keep the number.
How the process actually runs
- You sign up with the new provider and give them the exact billing details on the old account
- They submit a port request to the losing provider on your behalf
- The losing provider validates the details and agrees a date
- The number cuts over on that date, usually mid-morning
- You cease the old service afterwards — never before
Single numbers typically take around ten to fifteen working days. A block of numbers or an ISDN range can take three to six weeks because the ranges are moved as a whole.
The cutover window — be told this upfront
Anyone promising a completely seamless port is overselling it. On cutover day there is a short window where the number has left the losing network and has not yet been fully picked up by the new one. Calls during that window may not connect.
It's normally minutes. It is planned for, not prevented: pick a quiet mid-week morning, publish a mobile number as a fallback for the day, and keep the old service live until you've taken real calls on the new one.
What can block or delay a port
- Details that don't match the losing provider's records exactly — postcode, account number, business name
- An outstanding balance on the old account
- The number being registered to a former employee, a reseller or a dissolved company
- The line already having a cease order on it
- Non-geographic numbers with specific routing arrangements
Mismatched details cause the overwhelming majority of rejections, and they cost days rather than weeks. Send a recent bill with the port request and most of it disappears.
Numbers you should think twice about
Numbers issued as part of a bundled package — a number that came free with a system, or one supplied by a reseller — are sometimes registered to the provider rather than to you. They are still usually portable, but confirm ownership before you plan the date.
If you're taking on a number from another business, the paperwork needs to show the transfer. We cover this in more detail in our guide on who owns your business number.
What we do
We handle the port paperwork, chase the losing provider and give you a date rather than a vague window. Porting is included in our current offer rather than billed as an extra.
If your line is with BT, the switching from BT page covers the account-side details specifically.
Want this set up for you?
Plans start at £19 per user per month with UK calls included. See pricing or get a quote.