03 numbers: 0300, 0303, 0330, 0333, 034 and 037

A UK number starting 03 is a non-geographic number that by Ofcom rule costs no more than a call to an ordinary 01 or 02 landline and counts towards inclusive minutes, from mobiles too. 0300 and 0303 are only for public sector and not-for-profit bodies, 0330 and 0333 can be used by any organisation, and 034/037 are for organisations moving off 084/087 numbers.

United Kingdom · Non-geographic numbers · Facts checked November 9, 2026

What these numbers look like

From abroad
+44 3XX XXX XXXX
Inside United Kingdom
03XX XXX XXXX

11 digits nationally. A 034 or 037 number keeps exactly the same digits as the 084 or 087 number it replaces, with only the second digit changed (0845 to 0345, 0870 to 0370).

Who uses UK 03 numbers?

Ofcom created the 03 range in 2007 and allocates it under the National Telephone Numbering Plan. The plan says providers given 030 numbers may assign them only to public sector or not-for-profit bodies, while 033 is open to any organisation. 034 and 037 are reserved for migrating matching 084 and 087 numbers, and a provider can't use one unless the matching 08 number is in use by the same customer. Calls to 03 are charged at up to the geographic rate, and revenue sharing is not allowed.

Who is calling you from a UK 03 number?

A 0300 or 0303 call usually comes from a government department, council, NHS service, regulator or charity, though caller ID can be spoofed. A 0330 or 0333 call is usually a business or call centre, because any organisation can use those numbers. 0345 and 0370 numbers often belong to banks, utilities and retailers that moved off 0845 and 0870.

What to do about a call from UK 03

  1. Calling back an 03 number costs the same as calling an 01/02 number, and it's included in most bundles, mobile ones too.
  2. A 0300 caller ID doesn't prove the call is from a public body, because numbers can be spoofed. If the caller asks for payment or personal details, hang up and call the organisation on a number from its official website or a letter.
  3. Report scam calls to Report Fraud (reportfraud.police.uk, 0300 123 2040), or to Police Scotland on 101. Forward scam texts free to 7726.

Check the exact number

A series tells you what kind of line called. To check the full number you got, use these free tools:

Frequently asked questions

Is a 0300 number free to call?

Not free, but it costs no more than calling a standard 01 or 02 number, and it counts towards inclusive minutes on landlines and mobiles.

Who uses 0300 numbers?

Only public sector and not-for-profit bodies, such as government departments, councils, NHS services and registered charities. Ofcom's numbering plan restricts the 030 range to them.

What is the difference between 0300 and 0333?

They cost the same to call. 0300/0303 are restricted to public and not-for-profit bodies, while 0330/0333 can be used by any organisation.

Why did my company's 0845 number become 0345?

Ofcom reserved 034 and 037 so organisations can move from 084/087 to the same digits at landline rates, without the service charge.

Sources

Numbering facts on this page come from the regulator or operator sources below, checked November 9, 2026. We never publish individual personal phone numbers.

  • Ofcom - What are 03 numbers? (ofcom.org.uk)
  • Ofcom - Guidance on bodies eligible to use '030' telephone numbers (ofcom.org.uk)
  • Ofcom - The National Telephone Numbering Plan (version with effect from 22 April 2025) (ofcom.org.uk)
  • Ofcom - The '03' number allocation process (13 February 2007) (ofcom.org.uk)
  • Ofcom - UK Calling (service number charges since 1 July 2015) (ofcom.org.uk)
  • GOV.UK - Report Fraud: new service from City of London Police (replaces Action Fraud from 4 December 2025) (gov.uk)
  • Ofcom - How to report scam texts and mobile calls to 7726 (ofcom.org.uk)

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