- Prefix
01720 4- Area
- Isles of Scilly
- Number type
- Geographic landline (01/02)
- Format
01720 4XXXXX- From abroad
+44 1720 4XXXXX- Ofcom blocks in range
- 19
- Blocks in service
- 15
- Range holders
- 15
What are 01720 4XXXXX numbers?
Any UK number matching 01720 4XXXXX sits in the
01720 dialling code for Isles of Scilly.
Ofcom hands these numbers to communications providers in blocks; this range
contains 19 blocks, of which
15 are allocated and usable. Calls from these
numbers are typically homes and businesses in the Isles of Scilly area — or
organisations elsewhere that keep a local 01720 presence using
VoIP.
Who holds 01720 4… number ranges?
| Range holder (allocated by Ofcom) | Number blocks | Example range |
|---|---|---|
| API Telecom Limited | 1 | 01720 431XXX |
| BT | 1 | 01720 42XXXX |
| Content Guru Limited | 1 | 01720 436XXX |
| Flextel Limited | 1 | 01720 48XXXX |
| Gamma Telecom Holdings Limited | 1 | 01720 41XXXX |
| Hello Telecom (UK) Limited | 1 | 01720 432XXX |
| IOVOX Limited | 1 | 01720 437XXX |
| Invoco Ltd | 1 | 01720 435XXX |
| Linear Telecoms Limited | 1 | 01720 430XXX |
| Magrathea Telecommunications Limited | 1 | 01720 45XXXX |
| Minotaur Telecom Limited | 1 | 01720 438XXX |
| Net-Work Internet Ltd | 1 | 01720 49XXXX |
…and 3 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 19 blocks Ofcom lists, 4 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 01720 4… number safe?
A local-looking number is never proof of who is calling: fraudsters spoof 01720 caller IDs so their calls look like they come from Isles of Scilly (‘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 01720 4XXXXX 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.
More 01720 number ranges
Full 01720 Isles of Scilly area-code guide › · All UK area codes ›