- Prefix
020 3- Area
- London
- Number type
- Geographic landline (01/02)
- Format
020 3XXX XXXX- From abroad
+44 20 3XXX XXXX- Ofcom blocks in range
- 1,000
- Blocks in service
- 921
- Range holders
- 169
What are 020 3XXX XXXX numbers?
Any UK number matching 020 3XXX XXXX sits in the
020 dialling code for London.
Ofcom hands these numbers to communications providers in blocks; this range
contains 1,000 blocks, of which
921 are allocated and usable. Calls from these
numbers are typically homes and businesses in the London area — or
organisations elsewhere that keep a local 020 presence using
VoIP.
Who holds 020 3… number ranges?
| Range holder (allocated by Ofcom) | Number blocks | Example range |
|---|---|---|
| BT | 230 | 020 3007 XXXX |
| Gamma Telecom Holdings Limited | 138 | 020 3002 XXXX |
| Colt Technology Services | 77 | 020 3003 XXXX |
| Sky UK Limited | 56 | 020 3015 XXXX |
| Verizon UK Limited | 42 | 020 3008 XXXX |
| Vodafone Ltd (C&W) | 37 | 020 3063 XXXX |
| TalkTalk Communications Limited | 31 | 020 3092 XXXX |
| Magrathea Telecommunications Limited | 17 | 020 3051 XXXX |
| GCI Network Solutions Limited | 11 | 020 3020 XXXX |
| Resilient Limited | 11 | 020 3162 XXXX |
| Virgin Media Limited | 11 | 020 3028 XXXX |
| Lumen Technologies UK Limited | 9 | 020 3014 XXXX |
…and 157 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 1,000 blocks Ofcom lists, 73 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.
How often is 020 3… checked?
78 people checked a 020 3… number with this tool in the four weeks to 20 September 2026. That makes it the most-checked 020 London range on this site out of 239 with any checks at all. Checks were up 20% in the latest week compared with the week before.
Checks per week (weeks ending on the dates shown). Our own lookup data, counted once per person per number per day, with Ofcom’s drama/example ranges excluded and refreshed weekly. It measures how many people were curious enough to check a number in this range — it is not a count of scam calls, and it says nothing about any individual number. The quarterly nuisance-call prefixes report puts every range side by side.
Is a call from a 020 3… number safe?
A local-looking number is never proof of who is calling: fraudsters spoof 020 caller IDs so their calls look like they come from London (‘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 020 3XXX XXXX 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.
More 020 number ranges
Full 020 London area-code guide › · All UK area codes › · Nuisance-call data & reports ›