- Range holder
- Colt Technology Services
- Ofcom blocks allocated
- 2,020
- Dialling codes covered
- 596
- Number types held
- 9
- Largest single area
- 020 London
- Data source
- Ofcom numbering data
Who is Colt Technology Services?
Colt Technology Services is the name Ofcom records as the range holder for 2,020 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 596 of the UK’s 599 dialling codes — the allocation pattern of a national landline or VoIP provider rather than a local one.
Colt Technology Services’s footprint by number type
| Number type | Allocated blocks |
|---|---|
| Geographic landlines (01/02) | 1,693 |
| Personal numbering (070) | 24 |
| UK-wide 03 numbers | 110 |
| Freephone (0800 / 0808) | 33 |
| 084 service numbers | 23 |
| 087 service numbers | 40 |
| 089 service numbers | 2 |
| Premium rate (09) | 88 |
| 055 corporate & 056 VoIP | 7 |
Where Colt Technology Services’s landline numbers are
Colt Technology Services holds geographic (01/02) blocks in 596 dialling-code areas. These are the codes where they hold the most:
| Dialling code | Area | Allocated blocks |
|---|---|---|
020 | London | 216 |
028 | Northern Ireland | 43 |
01223 | Cambridge | 23 |
01483 | Guildford | 18 |
01865 | Oxford | 17 |
01224 | Aberdeen | 16 |
01273 | Brighton | 14 |
01753 | Slough | 14 |
01908 | Milton Keynes | 14 |
01202 | Bournemouth | 13 |
01582 | Luton | 12 |
0161 | Manchester | 12 |
…plus smaller allocations in 584 more dialling codes.
Number ranges Colt Technology Services holds
The ranges where Colt Technology Services holds the largest allocations. Each one links to a full guide showing every provider in that range:
…and 931 more ranges across the numbering plan.
What a call from a Colt Technology Services range means
If our phone number checker shows Colt Technology Services for a number, it means Ofcom allocated the block that number sits in to Colt Technology Services. 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 Colt Technology Services, 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 Colt Technology Services 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.
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 ›