0203 and 0207 London numbers

Updated 2026-05-02

020 is the London dialling code. 0207 numbers are older (ex-Inner London), 0203 numbers are newer allocations, and 0204 is more recent still. None of them is automatically safer or more dangerous — but London prefixes are a favourite of scammers running 'investment' and 'compliance' scripts because they sound corporate.

Why scammers love London prefixes

A 0203 number sounds like a Canary Wharf trading desk. Boiler-room scams selling fake shares, crypto, or 'recovery services' for previous fraud losses lean on this perception heavily.

How to verify a London business

Cross-check the company name on the FCA register (register.fca.org.uk) for any financial services pitch. Check Companies House (find-and-update.company-information.service.gov.uk) for incorporation details. A genuine business will match.

Red flags

  • Cold call about investments, crypto, or 'recovering' previous losses
  • Company not on the FCA register
  • Pressure to act before 'the offer closes'
  • Request to set up an account on a platform you've never heard of

What to do

  1. Don't commit on the call. Ask for everything in writing.
  2. Verify on FCA register and Companies House.
  3. Report to the FCA if they're offering regulated services without authorisation.
  4. Search the number on WhoCalledMe.ai.

Frequently asked questions

Is a 0203 number always London-based?

The geographic prefix is London, but VoIP providers can issue 0203 numbers to anyone, anywhere. Don't assume a London prefix means a London office.