03 non-geographic range
0333
Who called you from 0333?
Calls from 0333 numbers usually come from organisations rather than individuals: helplines, switchboards, customer service teams and outbound call centres. The allocation data below shows which phone companies hold 0333 numbers.
Was it a scam?
The code alone can't tell you, and anyone who says otherwise is guessing. What settles it is the call itself: a genuine organisation survives you hanging up and ringing back on the number from its website or your paperwork. If the caller wanted money, bank details, one-time codes or remote access to your computer, treat it as hostile.
What to do now
- Missed call, no voicemail? Don't ring back numbers you don't recognise. Anything important comes back properly.
- Suspicious call: forward the number and what was said to 7726, free on every UK network.
- Lost money or gave away details: Action Fraud, 0300 123 2040 (Police Scotland on 101 in Scotland), and your bank on the number on your card.
- If a caller claims to be from a government department, ring the department back on its official number, which ContactNumbers lists with the source.
- Full walkthrough in the report a call guide.
03 non-geographic range: what the register shows
0333 is a UK non-geographic range. Ofcom's register shows 235 allocated blocks held by 135 operators. Gamma Telecom Holdings Limited holds the most, with 21 of the 235 allocated blocks. Data retrieved 2026-10-22.
- Allocated blocks
- 235
- Operators
- 135
- Free or protected
- 763
- Share allocated
- 24%
Which companies hold 0333 numbers
Ofcom allocates numbers to phone companies in blocks. These are the operators holding the most 0333 blocks. The company that was issued a number often supplies it onward to a business or reseller, and UK numbers can be ported between networks, so read this as where the number started, and a strong hint rather than proof of who serves it today.
| Operator | Blocks held | Share of allocated |
|---|---|---|
| Gamma Telecom Holdings Limited | 21 | 9% |
| Colt Technology Services | 16 | 7% |
| GCI Network Solutions Limited | 13 | 6% |
| TalkTalk Communications Limited | 9 | 4% |
| Glide Student and Residential Limited | 8 | 3% |
| Windsor Telecom Limited | 6 | 3% |
| Vodafone Ltd (C&W) | 5 | 2% |
| Numbers Telecom Limited | 4 | 2% |
| BT | 3 | 1% |
| Barritel Limited | 3 | 1% |
| Magrathea Telecommunications Limited | 3 | 1% |
| Redcentric Solutions Limited | 3 | 1% |
Plus 123 further operators with smaller holdings.
What it costs to call 0333
Same price as calling a landline
Ofcom rules say 03 numbers must cost the same as calling an 01 or 02 number, and they must come out of your inclusive minutes if you have them. A company can't make money from you calling its 03 number.
Inclusive minutes: Yes, by regulation. See the full UK call charges guide.
Questions people ask about 0333
What is a 0333 number?
0333 is a UK 03 non-geographic range. 135 operators hold number blocks in this range according to Ofcom's allocation data.
Who called me from 0333?
Calls from 0333 numbers usually come from organisations rather than individuals: helplines, switchboards, customer service teams and outbound call centres. The allocation data below shows which phone companies hold 0333 numbers.
How much does it cost to call 0333 numbers?
Same price as calling a landline. Full details in the cost section above.
Is a call from 0333 a scam?
The code alone can't tell you. Most calls from 0333 numbers are legitimate, but scammers can dial from, or pretend to dial from, any range. Never hand over passwords, PINs or remote computer access to an inbound caller. If in doubt, hang up and call the organisation back on the number printed on its website or your paperwork.
How do I report a nuisance or scam call?
Forward scam call details to 7726 (free, all UK networks), report fraud to Action Fraud on 0300 123 2040, and report persistent nuisance calls to the ICO. Our report a call guide walks through each route.
Source: Ofcom telephone numbering allocation data, retrieved 2026-10-22 and reproduced with acknowledgement under Ofcom's re-use terms. Figures describe number blocks, and a block being allocated to an operator says nothing about any individual caller. Last verified by a human on 2026-10-22.