Who Called Me from 01833 (Barnard Castle)?
01833 is the Barnard Castle dialling code across 106 Ofcom-allocated number blocks. Look up who called from a 01833 number, identify the network operator, check against known scam patterns and report unwanted calls.
01833 is the UK dialling code for Barnard Castle, in the historic county of County Durham, covering an area with a population of approximately 5,610. Numbers in this area follow the format 018331234567 — the dialling code, followed by a local number assigned to a specific Communications Provider (CP).
Ofcom has allocated 106 number blocks within the 01833 range, spread across BT, Virgin Media, Sky, TalkTalk, Gamma and many smaller UK CPs. Each block of 1,000 (or sometimes 10,000) numbers is owned by a single CP, which may then assign individual numbers to its own customers or to resellers further down the chain. You can see the full block-by-block allocation list below.
Although 01833 originally indicated the geographic location of the line, UK number portability means a phone with this prefix can technically be located anywhere. For most landlines the geographic match still holds, but for VoIP-only numbers it does not. If you receive a call from a 01833 number and you don't recognise it, you can match the next four digits (the "block") against the table below to identify the originally-allocated network operator.
Ofcom-allocated blocks for 01833
These are the 106 currently-active number blocks Ofcom has allocated within the 01833 range, in order. Click any block to see the carrier, allocation date and recently-reported call patterns.
