- Range holder
- Datazero Ltd
- Ofcom blocks allocated
- 558
- Dialling codes covered
- 427
- Number types held
- 6
- Largest single area
- 028 Northern Ireland
- Data source
- Ofcom numbering data
Who is Datazero Ltd?
Datazero Ltd is the name Ofcom records as the range holder for 558 UK number blocks. Ofcom publishes which communications provider each block of the national numbering plan was allocated to; it does not publish what those numbers are used for or who uses them, so everything on this page is the footprint, not the customer list.
Their allocation is overwhelmingly geographic landline ranges, spread across 427 of the UK’s 599 dialling codes — the allocation pattern of a national landline or VoIP provider rather than a local one.
Datazero Ltd’s footprint by number type
| Number type | Allocated blocks |
|---|---|
| Geographic landlines (01/02) | 523 |
| Personal numbering (070) | 2 |
| UK-wide 03 numbers | 6 |
| Freephone (0800 / 0808) | 21 |
| 084 service numbers | 5 |
| 087 service numbers | 1 |
Where Datazero Ltd’s landline numbers are
Datazero Ltd holds geographic (01/02) blocks in 427 dialling-code areas. These are the codes where they hold the most:
| Dialling code | Area | Allocated blocks |
|---|---|---|
028 | Northern Ireland | 13 |
0191 | Tyneside / Durham / Sunderland | 5 |
020 | London | 5 |
0161 | Manchester | 3 |
023 | Southampton / Portsmouth | 3 |
0115 | Nottingham | 2 |
0116 | Leicester | 2 |
0118 | Reading | 2 |
01206 | Colchester | 2 |
01223 | Cambridge | 2 |
01227 | Canterbury | 2 |
01243 | Chichester | 2 |
…plus smaller allocations in 415 more dialling codes.
Number ranges Datazero Ltd holds
The ranges where Datazero Ltd holds the largest allocations. Each one links to a full guide showing every provider in that range:
…and 466 more ranges across the numbering plan.
What a call from a Datazero Ltd range means
If our phone number checker shows Datazero Ltd for a number, it means Ofcom allocated the block that number sits in to Datazero Ltd. That is genuinely useful — it tells you the number is a real, allocated UK number of a known type — but three caveats matter:
- It is not the caller. The person or business on the other end is a customer of Datazero Ltd, or of a reseller buying numbers wholesale from them.
- It may not even be their network any more. Numbers are ported between providers all the time, and Ofcom’s data keeps showing the original allocation.
- Caller ID can be faked. Spoofing lets a fraudster display any number, including one from a Datazero Ltd range they have nothing to do with.
Ofcom’s data shows the provider each number range was originally allocated to — not who holds an individual number today. Numbers are frequently moved (ported) between providers, and no public database reveals the person or business behind a specific number, so treat any service that claims to with suspicion.
Had an unexpected call from one of these numbers?
Check the number itself rather than the provider name. Our guide to the UK number ranges scammers use covers the patterns worth knowing, and who called me? walks through identifying a caller honestly. Forward scam texts free to 7726, and report scam calls to Action Fraud.
Run mobiles for a business? See our business mobile network comparison or get a quote.
Other UK range holders
Operators with a similar-sized share of the numbering plan:
All UK range holders › · All UK number ranges › · All UK area codes ›