UK area code
01603 — Norwich
The 01603 dialling code covers Norwich in Norfolk. Approximate population of the area: 144,000. Below are the currently-allocated Ofcom number ranges and the Range Holders they are assigned to.
About the 01603 dialling code
01603 is the UK area code for Norwich and the surrounding Norfolk area, listed in Ofcom’s National Telephone Numbering Plan. When a UK landline calls you and the number begins +44 1603 the originating exchange is most likely physically located in or near Norwich. Numbers in this code are allocated to UK communications providers in 1,000- or 10,000-number blocks; the table below shows which Range Holder Ofcom assigned each block to.
This is the same data Ofcom publishes every Wednesday in the public UK Numbering Data feed. We re-ingest the snapshot weekly, so the allocations you see here are at most seven days old. Because UK numbers are portable, the current carrier of any specific number on 01603 can differ from the Range Holder shown — see Range Holder vs current provider for the full explanation.
To identify a specific 01603 number, paste it into the lookup form above. You will see the Range Holder, the allocation status, the area-code metadata for Norwich, and a live AI internet check summarising any public web reports about that exact number — useful when an unfamiliar 01603 caller turns out to be a legitimate local business, a national contact-centre, or a scam.
Range holders on 01603
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All allocated ranges on 01603
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Related lookups
FAQs about 01603
What does the 01603 area code cover?
01603 is the UK dialling code for Norwich and the wider Norfolk area. The area has a population of approximately 144,000. When you receive a call starting with 01603 from a UK landline, the originating exchange is likely in or near Norwich.
Is a 01603 number safe?
Most calls from 01603 are legitimate landlines. Scammers can however spoof any UK area code, so a 01603 prefix alone doesn't guarantee safety. Use the lookup above to see the Range Holder, then read the AI internet check for behavioural reports.
How many providers operate 01603 number ranges?
Across the 0 ranges currently visible, 0 different Range Holders are listed. The top allocations are typically held by Openreach (BT), Virgin Media O2 and Sky.