How the UK phone number checker works

Every UK telephone number is allocated by Ofcom, the communications regulator, under the National Telephone Numbering Plan. Numbers are handed out to communications providers in blocks, and Ofcom publishes exactly which provider holds each block and which geographic area each dialling code belongs to. This tool matches the number you enter against that official data using a longest-prefix lookup, then tells you the number’s type, area and allocated provider.

Important: this tool tells you the provider a number range was allocated to and the area of the dialling code. It cannot tell you the name of the person or business that holds a specific number, and numbers are frequently ported between providers, so the current network may differ from the original range holder. Be very wary of any service that claims to reveal who personally owns a number.

UK phone number formats explained

UK numbers are normally written starting with a 0 (the trunk prefix). From abroad you drop the 0 and add +44 — so 020 7946 0000 becomes +44 20 7946 0000. The first few digits (the prefix) tell you what kind of number it is and roughly what it costs to call:

Starts withNumber typeWhat it means & call cost
01 & 02Geographic landlinesTied to a town or city area code (e.g. 020 London, 0161 Manchester). Charged as a normal landline call.
03UK-wide non-geographic0300/0330/0345/0370 numbers cost the same as 01/02 and count towards inclusive minutes - used by charities, government and businesses.
055Corporate numberingCompany-wide numbers that aren't tied to one location.
056VoIP / internet numbersLocation-independent voice-over-IP numbers.
070Personal numbers‘Follow-me’ numbers that look like a mobile but are not - they can be expensive and are a common scam disguise.
071-075, 077-079MobileStandard UK mobile numbers (076 is radiopaging).
080 (0800 / 0808)FreephoneFree to call from UK landlines and mobiles.
084 (0843 / 0844 / 0845)Service numbersUp to 7p/min plus your provider's access charge.
087 (0870 / 0871 / 0872 / 0873)Service numbersUp to 13p/min plus your provider's access charge.
09 (090 / 091 / 098)Premium rateCan cost several pounds per minute plus access charge - treat with caution.
116Harmonised helplinesFree-to-call helplines such as 116 123 (Samaritans).
118Directory enquiriesDirectory services that can be very expensive.

UK area codes for major cities

Geographic 01 and 02 numbers are tied to a town or city. The checker resolves the full area name for any geographic number; here are some of the best-known dialling codes:

  • 020 London
  • 0121 Birmingham
  • 0161 Manchester
  • 0113 Leeds
  • 0114 Sheffield
  • 0117 Bristol
  • 0118 Reading
  • 0131 Edinburgh
  • 0141 Glasgow
  • 0151 Liverpool
  • 0191 Newcastle / Tyneside
  • 028 Northern Ireland
  • 029 Cardiff
  • 01282 Burnley
  • 01202 Bournemouth
  • 01223 Cambridge

London (020), Southampton/Portsmouth (023), Coventry (024), Northern Ireland (028) and Cardiff (029) use a 2–3 digit area code followed by an 8-digit local number; most other areas use a longer 4–5 digit code.

How to identify or trace where a number is from

To work out where a UK number is from and who is behind it:

  1. Check the prefix — paste it into the checker above to see whether it’s a landline, mobile, freephone or premium number.
  2. Look at the area code — for 01/02 numbers the code maps to a specific town or city.
  3. Note the allocated provider — Ofcom’s data shows which communications provider the range belongs to (bearing in mind porting).
  4. Search the full number — if it’s a business, the digits often appear on their website or listings.

Spotting spam, scam and nuisance calls

Fraudsters often hide behind certain ranges. Be cautious if you see:

  • 070 ‘personal’ numbers dressed up to look like mobiles — they can cost far more to call.
  • 09 premium-rate numbers you’re asked to ring back.
  • Withheld or international numbers claiming to be your bank.
  • Spoofed numbers — scammers can fake the caller ID, so a familiar-looking number is not proof of who is calling.

Never give out personal or banking details to an unexpected caller. Hang up and call the organisation back on a number you find independently. If you’re just trying to put a name to a caller, see who called me? and is this number a scam?; to report one, see how to report a scam number. You can also report nuisance calls to the ICO and forward scam texts to 7726.

Call charges by prefix

Since 2015, calls to 084, 087, 09 and 118 numbers are split into an access charge (set by your phone provider, per minute) and a service charge (set by the organisation you’re calling). 080 freephone numbers are free from UK landlines and mobiles. 03 numbers always cost the same as 01/02 calls and are included in inclusive minutes — which is why so many business phone systems use them.

Choosing the right number for your business

The number you advertise shapes how customers perceive you and what it costs them to call. A local 01/02 number signals a local presence; an 03 number is national but caller-friendly; an 0800 freephone number can boost response rates. With hosted telephony (VoIP) you can run any of these, keep your existing number when you switch by porting it, and add features like auto-attendants and call recording. If you’d like help choosing, our team is happy to talk it through.