UK range holders A–Z

What a “range holder” actually is

Ofcom doesn’t allocate individual phone numbers to end users. Instead, it hands out blocks — most commonly 1,000 or 10,000 consecutive numbers within a given dialling code — to licensed Communications Providers. Those providers then either issue the numbers to their own customers (BT, Sky, Virgin Media, EE, O2, Three, Vodafone) or sub-allocate the block to a smaller business carrier (Gamma, TalkTalk Business, Daisy, Magrathea, Voxbone / Bandwidth) who in turn rent numbers to VoIP, contact-centre and SaaS resellers. The provider listed against any given prefix on this site is the current holder, which can change when a block is ported, returned, withdrawn or re-issued.

Why the holder matters when a call comes in

Knowing the range holder is the single most useful first signal when you don’t recognise a caller. A 0203 number assigned to a major reseller used heavily by call-centre clients is far more likely to be a cold-call than a 0203 issued by BT to a residential line in central London. A 070 personal number registered to a shell-style range holder is far more likely to be a scam-spoof than one issued by an established CP — 070 prefixes look like mobiles to most consumers but charge premium-rate, and scammers buy cheap blocks specifically to exploit that confusion. The holder also tells you which company to report the number to: most UK CPs publish a published abuse address (typically abuse@<provider>) and act on credible spam complaints quickly because Ofcom can fine them for allowing nuisance traffic to persist.

How the data on this page is built

Holders below are scraped from Ofcom’s public Numbering Data spreadsheet, deduplicated by canonical company name (with manual override slugs where Ofcom records a holder under two slightly different legal names) and joined to our internal blocks table. The count on the right of each row is the number of 1,000- / 10,000-number ranges currently allocated to that holder; tap through to see them grouped by dialling code. Counts and allocations refresh weekly via the Ofcom feed.