The 03 number range is the backbone of modern UK business telephony. Whether you’re calling a bank on 0345, a telecoms provider on 0333, or a charity on 0300, you’re using the same family of numbers — all governed by the same simple Ofcom rule: they cost no more than a geographic call, and they must be included in your bundled minutes. This guide brings together everything you need to know about the entire 03 range.
What Are 03 Numbers?
03 numbers are a family of UK non-geographic telephone numbers introduced by Ofcom. “Non-geographic” means they are not linked to any city, town, or region — unlike 01 and 02 numbers that identify a specific area (0121 = Birmingham, 020 = London, etc.).
The 03 range was created with one core principle: calls to 03 numbers must always cost the same as calls to geographic 01/02 numbers. This means they’re included in your mobile plan’s bundled minutes, making them effectively free for the vast majority of UK phone users.
The three main 03 prefixes are:
- 0300 — reserved for charities, non-profits, and public-sector bodies
- 0333 — available to all businesses, the most widely used 03 prefix
- 0345 — available to all businesses, commonly used by banks and utilities that migrated from 0845
Why Did Ofcom Create 03 Numbers?
Before 03 numbers existed, businesses that wanted a non-geographic phone number had limited choices — mainly 0845 and 0870. Both of these carried problems:
- 0845 and 0870 were expensive from mobiles — callers could be charged up to 72p per minute, often without realising it
- Revenue sharing meant businesses profited from incoming calls — creating a perverse incentive to keep callers on hold or in long queues
- Not included in bundled minutes — even customers with “unlimited calls” plans were charged extra for 08 numbers
- Public distrust — surveys showed UK consumers actively avoided calling 0845/0870 numbers due to cost concerns
Ofcom launched the 03 range in 2007 to solve all of these problems at once. The rules are clear and non-negotiable:
- 03 calls must cost no more than a geographic (01/02) call
- 03 calls must be included in inclusive minutes bundles
- Revenue sharing is completely banned on 03 numbers
- Phone providers must not charge more for 03 than for 01/02
Get a 03 business number with cloud VoIP — plans from £12/user/month
How Much Does It Cost to Call 03 Numbers?
All 03 numbers — whether 0300, 0333, or 0345 — follow the same pricing:
- From a mobile with inclusive minutes: Free — uses your bundled minutes
- From a mobile without inclusive minutes: Same rate as a geographic 01/02 call
- From a UK landline: Included in call packages or charged at standard rates
- From abroad: Charged as a UK call by your international provider (dial +44 3xx)
Given that over 95% of UK mobile plans include bundled minutes, calling any 03 number is free for the vast majority of people.
The Three 03 Prefixes Compared
0300 — For Charities and Public Bodies
0300 numbers are restricted to registered charities, not-for-profit organisations, and public-sector bodies. Used by NHS 111, HMRC, Action Fraud, Citizens Advice, local councils, and many charities. The restriction creates implicit trust — callers know they’re dealing with a non-commercial organisation. Read our full 0300 guide.
0333 — For All Businesses
0333 is the most common 03 prefix and is available to any UK business. It’s used by telecoms providers (including Connection Technologies), insurers, retailers, SaaS companies, professional services firms, and startups. The largest range of available numbers, including memorable “gold” numbers. Read our full 0333 guide.
0345 — Popular with Banks and Utilities
0345 was positioned as the direct replacement for 0845. Identical pricing and rules to 0333. Commonly used by HSBC, Barclays, British Gas, Scottish Power, DVLA, and other large organisations that migrated from 0845. Read our full 0345 guide.
03 Numbers vs Other UK Number Types
03 vs 0845
03 numbers replaced 0845 as the recommended non-geographic choice. The differences are dramatic: 03 is included in bundled minutes (0845 is not), 03 bans revenue sharing (0845 allows it), and 03 costs geographic rate (0845 costs up to 72p/min from mobiles). See our 0845 guide.
03 vs 0800
0800 is completely free for callers — the business pays per minute. 03 numbers are geographic rate (free from bundled minutes) and the business does not pay per minute for inbound calls. Both are good choices; 0800 maximises inbound calls at a cost to the business, while 03 gives a customer-friendly experience with no per-call charge to the business. See our 0800 guide.
03 vs 01/02 Geographic
Same cost for callers. The choice is about branding: 01/02 ties you to a specific city (great for local businesses), while 03 is location-neutral (great for national businesses or remote teams). Many businesses use both — a 0333 for national marketing and an 01/02 number for local presence. Our area code guides explain geographic numbers in detail.
How to Get a 03 Number for Your Business
Getting a 03 number is quick and easy in 2026:
- Choose your prefix: 0333 for commercial businesses, 0300 for charities/public bodies, or 0345 if you prefer
- Sign up with a VoIP provider:Hypercloud from Connection Technologies includes your choice of 03 number with hosted phone plans from £12 per user per month
- Select your specific number: Browse available numbers and choose a memorable sequence
- Configure call routing: Route calls to desk phones, mobiles, ring groups, auto-attendants, or call queues
- Go live: Your 03 number can be active within 24 hours. Porting an existing number takes 5–10 working days
Get your 03 business number today — VoIP plans from £12/user/month
Frequently Asked Questions
03 numbers cost the same as a standard 01/02 geographic call. Since virtually all UK mobile and landline plans include geographic numbers in their bundled minutes, calling a 03 number is effectively free for most people. They are not premium rate and revenue sharing is banned.
All three cost the same to call and follow the same Ofcom rules. 0300 is restricted to charities, non-profits, and public-sector organisations. 0333 is the most common prefix and available to any business. 0345 is also available to any business and is commonly used by those that migrated from 0845 (banks, utilities).
Yes. Ofcom requires that all 03 numbers are included in inclusive minute bundles on the same basis as 01/02 geographic numbers. If your mobile plan includes calls to UK landlines, it includes calls to 03 numbers.
03 numbers are included in bundled minutes (0845 is not), cost geographic rate rather than up to 72p/min, and ban revenue sharing. Consumers trust 03 numbers and are more likely to call them. Ofcom actively recommends migrating from 0845 to 03.
Unlike 0800 freephone numbers, businesses don’t pay a per-minute charge for inbound calls to their 03 number. The only cost is your phone system or VoIP plan. With Hypercloud from Connection Technologies, plans including a 03 number start from £12 per user per month.
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