- Prefix
01923 5- Area
- Watford
- Number type
- Geographic landline (01/02)
- Format
01923 5XXXXX- From abroad
+44 1923 5XXXXX- Ofcom blocks in range
- 100
- Blocks in service
- 72
- Range holders
- 55
What are 01923 5XXXXX numbers?
Any UK number matching 01923 5XXXXX sits in the
01923 dialling code for Watford.
Ofcom hands these numbers to communications providers in blocks; this range
contains 100 blocks, of which
72 are allocated and usable. Calls from these
numbers are typically homes and businesses in the Watford area — or
organisations elsewhere that keep a local 01923 presence using
VoIP.
Who holds 01923 5… number ranges?
| Range holder (allocated by Ofcom) | Number blocks | Example range |
|---|---|---|
| Sky UK Limited | 7 | 01923 562XXX |
| TalkTalk Communications Limited | 6 | 01923 510XXX |
| Vodafone Ltd (C&W) | 5 | 01923 525XXX |
| Calltracks Limited | 2 | 01923 556XXX |
| Gamma Telecom Holdings Limited | 2 | 01923 587XXX |
| 24 Seven Cloud Communications Ltd | 1 | 01923 580XXX |
| Andrews & Arnold (Numbers) Ltd | 1 | 01923 536XXX |
| Atomstream Limited | 1 | 01923 550XXX |
| BT | 1 | 01923 545XXX |
| Barritec Limited | 1 | 01923 531XXX |
| Barritel Limited | 1 | 01923 532XXX |
| Bicom Systems EURL | 1 | 01923 584XXX |
…and 43 more providers hold smaller allocations in this range.
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.
Not every block in this range is in service: of the 100 blocks Ofcom lists, 28 are protected (reserved by Ofcom and not in use). A call appearing to come from an unallocated block is a strong sign of a spoofed number.
Is a call from a 01923 5… number safe?
A local-looking number is never proof of who is calling: fraudsters spoof 01923 caller IDs so their calls look like they come from Watford (‘neighbour spoofing’). If an unexpected caller asks for personal, banking or one-time-code details, hang up and ring the organisation back on a number you find independently. To put a name to a caller, see who called me?; to report one, see how to report a scam number.
Check a specific 01923 5XXXXX number
Paste any full number into the checker above (or on the main phone number checker) to see its exact range holder and allocation status from this week’s Ofcom data.
Run mobiles for a business? See our business mobile network comparison or get a quote.