Geographic numbers

Area codes starting 0123

Ofcom’s numbering data lists 2,431 number ranges starting 0123, allocated to 136 providers. The largest holder is BT, with 7% of them.

Number type
Geographic numbers
01 / 02
Area
Various
6 area codes
Ofcom ranges
2,431
1,049 allocated
First allocated
1994
136 providers

Who were 0123 ranges given to?

Providers Ofcom allocated these number ranges to.

  • Not allocated to a provider1,382 ranges
  • BT160 ranges
  • Gamma Telecom Holdings Limited52 ranges
  • Vodafone Ltd (C&W)46 ranges
  • Sky UK Limited38 ranges
  • TalkTalk Communications Limited33 ranges
  • Virgin Media Limited29 ranges
  • Colt Technology Services25 ranges
  • GCI Network Solutions Limited25 ranges
  • Magrathea Telecommunications Limited12 ranges
  • Fuse 2 Communications Ltd12 ranges
  • Six Degrees Technology Group Limited12 ranges

+ 125 more

Range status

How Ofcom lists the ranges starting 0123.

Protected · 1,317 Allocated · 1,049 Free · 59 Quarantined · 6

Allocations by year

19942026

What do these statuses mean?

Explore by the next digit

Each block below starts 0123. Pick one to narrow it down.

What a 0123 number tells you

What it is

Ordinary landline numbers tied to a place. The area code tells you which dialling area the number was issued for – 0161 is Manchester, 020 is London, 01388 is Bishop Auckland.

What it costs

Charged as a normal UK call and usually included in landline and mobile allowances.

Watch out for

A local-looking number feels familiar, which is exactly why scammers spoof them. A local area code is not proof the caller is local.

The range holder isn’t necessarily the caller. Ofcom gives numbers to providers in blocks, and people and businesses can take their number with them when they switch. To find out who actually called, check the full number.
Questions

0123 numbers: common questions

Who owns 0123 numbers?

Ofcom allocated the ranges starting 0123 to BT, Gamma Telecom Holdings Limited, Vodafone Ltd (C&W) and others. Numbers can be moved between providers, so this shows who the range was originally given to – not who is using a particular number today.

How do I call a 0123 number from abroad?

Replace the leading 0 with +44. For example, a number starting 0123 becomes +44 123 followed by the rest of the number.

How much does it cost to call a 0123 number?

Charged as a normal UK call and usually included in landline and mobile allowances.

Is a call from a 0123 number a scam?

A local-looking number feels familiar, which is exactly why scammers spoof them. A local area code is not proof the caller is local. Check the full number on Who’s Calling to see if it belongs to a verified business and what other people have reported.

Did a 0123 number call you?

Check the full number to see if it belongs to a verified UK business and what other people have reported.

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