07700 900123

Who rang from 07700 900123?

This is in the mobile number range, but Ofcom’s data shows no phone company holding its block.

2 official sources · Ofcom files of 11 November 2026

This number is in a range Ofcom recommends for TV and radio drama. These ranges are never allocated to phone companies, so the number does not belong to anyone.

What should I do?

1
No provider holds this number in Ofcom’s data. Caller ID can be faked, and phone companies are required, where technically feasible, to block calls showing an invalid number. Be wary of any request for money or personal details.
2
If the caller said they were your bank, HMRC, a delivery company or another organisation, hang up and call back on a number from their official website or your statement, never one the caller gave you. The number on your screen can be faked.
3
If you think the call was a scam, send the number in a text to 7726. It is free, and your mobile provider can investigate and block the number. From your recent calls, copy the number and paste it into a new text to 7726.
4
Shared bank details or sent money? Contact your bank straight away using the number on the back of your card, or call 159 to be connected to your bank.
5
Lost money or details to a scam: report it to Report Fraud online or on 0300 123 2040 (England, Wales and Northern Ireland). In Scotland, call Police Scotland on 101.
6
Unwanted sales calls: register free with the Telephone Preference Service (online or on 0345 070 0707). It tells legitimate marketers not to call you but will not block scam calls. If a company keeps calling, complain to the ICO.

Will it cost me to call back?

From a landline, calls to mobiles are often in the allowance; where not, they are typically 10p to 20p a minute, plus a set-up fee that is usually 23p.

From a mobile, calls are normally in the allowance; outside it, they can cost between 3p and 65p a minute.

Typical prices from Ofcom’s guide. Your provider’s price list is what you actually pay.

What this cannot tell you

Who is using the number. Ofcom allocates numbers to phone companies in blocks and holds no information on individual numbers or the people and businesses using them.
Which network it is on today. People can keep their number when they change provider, so the company that holds the block may no longer be the one serving it.
Whether the call really came from this number. The number shown on your phone can be faked.

About this kind of number

Numbers starting 071 to 075 and 077 to 079 are mobile numbers. A mobile number is not linked to a place.

Check another number

Sources (15)Show

The National Telephone Numbering Plan (version with effect from 22 April 2025), Ofcom. Checked 11 November 2026.
Download numbering data, Ofcom. Checked 11 November 2026.
Telephone numbers for use in TV and radio drama programmes, Ofcom. Checked 11 November 2026.
Types of scam calls, texts and messages, Ofcom. Checked 11 November 2026.
Improving the accuracy of Calling Line Identification (CLI) data: statement, Ofcom. Checked 11 November 2026.
What to do about a scam call, text or message, Ofcom. Checked 11 November 2026.
159 Phone number, Stop Scams UK. Checked 11 November 2026.
Report Fraud, City of London Police. Checked 11 November 2026.
Contact us, Police Scotland. Checked 11 November 2026.
Telephone Preference Service, Telephone Preference Service. Checked 11 November 2026.
How to protect yourself from scam calls, texts and messages, Ofcom. Checked 11 November 2026.
Report spam texts and nuisance sales calls, Information Commissioner’s Office. Checked 11 November 2026.
Call costs guide, Ofcom. Checked 11 November 2026.
Freedom of Information request 01576747: telephone numbers (reply of 24 March 2023), Ofcom. Checked 11 November 2026.
Number Portability, Ofcom. Checked 11 November 2026.