01403 Area Code
The dialling code for Horsham: what 01403 numbers are, who holds them, and what to do about a call you don't recognise.
What Is the 01403 Area Code?
Horsham landline number. 01403 is the dialling code for Horsham. Numbers starting 01403 are landline numbers for that area. Internet phone services can use them too, so a caller is not necessarily in Horsham.
Who was the range allocated to?
Ofcom has allocated 01403 numbers to 98 providers. The largest holders are BT, Vodafone Ltd (C&W) and Gamma Telecom Holdings Limited.
Numbers can be moved (ported) between networks, so the network a caller uses today may not be the one Ofcom allocated the block to. The allocation does not identify the person or business using a number.
Had a call from a 01403 number you don't recognise?
We can't tell you who called: an area code only shows the type of number and the provider Ofcom allocated the range to.
- Don't call back in a hurry, even if a message says it's urgent. Never give bank details or security codes on a call you didn't expect.
- Block the number from your phone's recent calls list.
- Forward scam texts free to 7726. Report unwanted marketing calls to the ICO, and see Ofcom's advice on scam calls.
- Register your number with the Telephone Preference Service to opt out of sales calls.
About the 01403 Range
| Number type | Horsham landline number |
|---|---|
| Area | Horsham |
| Number format | 01403 XXXXXX |
| Allocated by Ofcom | 49% of the range, to 98 providers |
| First allocation on record | 15 July 1994 |
| Most recent allocation | 17 March 2026 |
Largest holders of 01403 numbers
| Provider (as allocated by Ofcom) | Share of range | First allocated |
|---|---|---|
| BT | 22% | 15 July 1994 |
| Vodafone Ltd (C&W) | 5% | 6 September 2013 |
| Gamma Telecom Holdings Limited | 2% | 1 March 2004 |
| GCI Network Solutions Limited | 1% | 25 April 2017 |
| AQL Wholesale Ltd | 1% | 1 November 2004 |
| Barritel Limited | 1% | 2 November 2006 |
92 more providers hold smaller blocks.
Allocation data: Ofcom numbering data, as published 28 October 2026.
Get Your Own 01403 Number
Want a Horsham number for your business? DigitalNumbers gives you one that rings on your existing mobile, with its own app, voicemail and WhatsApp Business support. 100+ numbers currently available.
- Make and receive calls using our included app
- Forwards calls to your existing mobile
- Works with WhatsApp Business
- Includes professional voicemail
- Lets you set working hours
Common Questions About 01403 Numbers
Where is the 01403 area code?
01403 is the dialling code for Horsham. Numbers starting 01403 are landline numbers for that area. Internet phone services can use them too, so a caller is not necessarily in Horsham.
Is 01403 a mobile number?
No. 01403 is a landline (geographic) area code for Horsham. UK mobile numbers start with 07.
Who does the 01403 range belong to?
Ofcom has allocated 01403 numbers to 98 providers. The largest holders are BT, Vodafone Ltd (C&W) and Gamma Telecom Holdings Limited. Numbers can be moved (ported) between networks, so the network a caller uses today may not be the one Ofcom allocated the block to. The allocation does not identify the person or business using a number.
Who called me from a 01403 number?
We can't tell you who called. An area code only shows the type of number and which provider Ofcom allocated the range to. If you don't recognise a 01403 number, don't call back in a hurry, and never give out bank details or security codes on a call you didn't expect.
Block the number from your phone's recent calls list. Forward scam texts free to 7726, report unwanted marketing calls to the ICO, and see Ofcom's advice on scam calls.