01923 area code — Watford

01923 is Ofcom's Watford numbering area, in Hertfordshire, East of England England. Its exchange town is in Hertfordshire. From abroad, drop the 0 and dial +44 1923.

Traditionally not from another 01923 landline, but it now depends on your provider: Ofcom stopped requiring providers to offer local (code-free) dialling on 11 March 2022. Dialling 01923 first always works, and mobiles always need it.

Numbers on 01923 use Ofcom's 4+6 format: the 5-digit code (including the leading 0) followed by a 6-digit local number — written like 01923 234 567. From abroad the leading zero is dropped: +44 1923 then the local number.

01923 took its current form at PhONEday on 16 April 1995, when a "1" was inserted into every UK geographic code — before that the area dialled 0923. Old signage or stationery showing 0923 refers to the same Watford numbers.

Ofcom lists 117 providers with allocated blocks on 01923. The largest are BT with 41 of the 300 allocated blocks, Gamma Telecom Holdings Limited with 30 of the 300 allocated blocks and Virgin Media Limited with 24 of the 300 allocated blocks. Numbers can be ported, so a number's current provider may differ from the block's holder.

By distance between exchange towns, the nearest other codes are 01727 St Albans (12 km), 01442 Hemel Hempstead (12 km), 01895 Uxbridge (13 km) and 01707 Welwyn Garden City (21 km).

On a mobile, text the caller's number to 7726 (free). If you lost money or shared details, call your bank and report it to Report Fraud (0300 123 2040), which replaced Action Fraud in December 2025. Unwanted sales calls go to the ICO after registering with the Telephone Preference Service.