- Ofcom rules require calls to 03 numbers to cost no more than calls to 01 and 02 geographic numbers from the same line and at the same time of day.
- Calls to 03 numbers must be included in any inclusive minutes or call allowances that cover 01 and 02 calls, under Ofcom's National Telephone Numbering Plan.
- The 03 range was introduced by Ofcom in 2007 as a non-geographic alternative for organisations that did not want to charge premium rates.
- Government departments and public bodies generally use 0300 numbers, while charities and not-for-profits often use 0300 or 0345 numbers.
- Unlike 084 and 087 numbers, 03 numbers carry no Service Charge, so the organisation cannot earn revenue from incoming calls.
An 03 number is a non-geographic UK number that costs the same as calling an 01 or 02 landline and counts towards inclusive minutes. It carries no premium charge.
Last reviewed: June 2026
What an 03 number actually is
Numbers starting 03 sit in a part of the UK numbering range that Ofcom set aside specifically so organisations could have a single national contact number without charging callers a premium. The prefix does not tie the holder to any town or city, which is the key difference from an ordinary 01 or 02 landline number. A charity headquartered in Manchester can publish the same 0300 number as a regional office in Cardiff, and callers from anywhere in the country reach it at the same rate.
The 03 range covers several sub-ranges, including 0300, 0330, 0343, 0344, 0345, 0370 and 0371. The leading digits do not change the cost to the caller. All of them fall under the same regulatory cap that ties the price to the cost of an equivalent geographic call. The range was opened by Ofcom in 2007, partly in response to public criticism that some public services and helplines were using higher-rate 084 and 087 numbers that left callers out of pocket.
How charges work on 03 calls
The defining rule of the 03 range is price equivalence. Under Ofcom's National Telephone Numbering Plan, a call to any 03 number must cost the caller no more than a call to a normal 01 or 02 number made from the same phone at the same time. If a landline tariff charges a few pence per minute for geographic calls, that is the maximum that can apply to an 03 call. If geographic calls are free within an inclusive package, then 03 calls must be free within that package too.
This equivalence extends to call allowances. Where a mobile or landline plan bundles a number of inclusive minutes that can be used on 01 and 02 numbers, those same minutes must cover 03 calls. The practical effect for most households on modern tariffs is that 03 calls come out of the same pot as any other landline call, and frequently cost nothing extra. The mechanism that makes this possible is the absence of a Service Charge: the organisation holding the 03 number receives no share of the call revenue, so there is nothing to pass on to the caller as a premium.
03 number rules compared with 01 and 02
The table below summarises how the 03 range is treated against ordinary geographic numbers and against the higher-rate 08 ranges, drawing on Ofcom's published numbering rules.
| Feature | 01 / 02 numbers | 03 numbers | 084 / 087 numbers |
|---|---|---|---|
| Tied to a geographic area | Yes | No | No |
| Cost to caller | Standard geographic rate | Same as 01 / 02 | Access Charge plus Service Charge |
| Counts towards inclusive minutes | Yes | Yes | No |
| Earns revenue for the holder | No | No | Yes, via Service Charge |
| Typical users | Local businesses, homes | Government, charities, national firms | Some commercial helplines |
Who uses 03 numbers and why
Central government has standardised heavily on the 0300 sub-range. Many GOV.UK contact lines, HM Revenue and Customs helplines, NHS services and local councils publish 0300 numbers precisely because Ofcom guarantees they will never cost a caller more than a normal landline call. For a public body, the appeal is reputational and practical: a single national number can be routed to whichever office or contact centre has capacity, while callers are reassured that they are not being charged a premium to reach a public service.
Charities and large national organisations follow the same logic. A helpline that wants to be reachable from across the UK, but that does not want to deter low-income callers with a premium rate, can take an 0345 or 0370 number and route incoming calls flexibly. Banks and utilities have also moved customer service lines onto 03 numbers in recent years, often replacing older 0845 lines after sustained public pressure about call costs. The common thread is that the holder values national reach and call routing flexibility but has no intention of profiting from inbound calls.
Why organisations prefer 03 over 08 numbers
The higher-rate 08 ranges split the cost of a call into two parts under Ofcom's unbundled tariff system: an Access Charge set by the caller's own phone company, and a Service Charge set by the organisation being called. Calls to 084 and 087 numbers can therefore be expensive and unpredictable, and they do not come out of inclusive minutes. This made them controversial, especially when used for essential services that callers could not easily avoid.
An 03 number sidesteps all of that. Because there is no Service Charge, the organisation earns nothing from the call, which removes any suggestion that it is profiting from people who need to get in touch. Crucially, the routing and non-geographic flexibility that organisations valued in 08 numbers is preserved: an 03 number can still be pointed at any office, queue or contact centre. For a charity, council or public-facing business, the 03 range offers the operational benefits of a national number without the public-relations cost of a premium tariff.
Things to check before switching a line to 03
For an organisation weighing up the 03 range, a few practical points are worth understanding. The first is that the price equivalence guarantee protects callers, not the holder: the organisation still pays its own provider for the inbound number service, and those wholesale costs vary between providers. The second is that an 03 number is fully portable and routable, so a single published number can be redirected between sites, queues or even out-of-hours answering arrangements without callers ever seeing a change. This makes the range well suited to organisations that reorganise their contact handling over time.
The third point concerns public perception. Because the 0300 sub-range in particular has become strongly associated with government and public services, some organisations choose it deliberately to signal that a call will not cost a premium. Others select 0330 or 0345 to achieve the same caller-cost outcome with a number that looks distinct from the public-sector ranges. For callers, none of these choices changes the price: every 03 number is capped at the geographic rate and included in inclusive minutes, so the sub-range is a branding decision rather than a cost one. Understanding this removes a common source of confusion, where people assume different 03 sub-ranges carry different charges.
Frequently Asked Questions
What is an 03 phone number?
An 03 number is a non-geographic UK telephone number that is not linked to any particular town or area. Ofcom created the range so organisations could publish a single national contact number while charging callers the same as a normal landline call. Sub-ranges include 0300, 0330, 0345 and 0370.
How much does it cost to call an 03 number?
A call to an 03 number costs no more than a call to an 01 or 02 landline from the same phone at the same time of day, because Ofcom caps the price at the geographic equivalent. On many tariffs this means the call is free if your geographic calls are free. The 03 prefix never carries a premium.
Are 03 numbers included in mobile minutes?
Yes. Under Ofcom's rules, any inclusive minutes or call allowance that covers 01 and 02 numbers must also cover 03 numbers. So if your mobile or landline plan includes minutes for ordinary landline calls, those minutes apply to 03 calls in the same way.
Why do organisations use 03 numbers?
Organisations use 03 numbers to have a single national contact number that can be routed flexibly between offices and contact centres, without charging callers a premium. Government departments, charities and large companies favour them because they reassure the public that there is no extra cost to call.
What is the difference between 03 and 0800 numbers?
An 0800 number is free to the caller, with the receiving organisation paying for the call. An 03 number is not free, but it costs the same as a normal landline call and comes out of inclusive minutes. Both avoid premium charges, but only 0800 is genuinely free at the point of calling.
