W1W postcode district

Postcodes and sectors

621 of the district's 850 postcodes are live in the ONS Postcode Directory of August 2026. A postcode directory says whether a code is in use, never who is there. The live postcodes centre on 51.51921, -0.14087, which locates the district, not a building.

Companies registered in W1W

Companies House lists 49,106 companies with a registered office in W1W; 46,030 of them at addresses shared by 25 or more companies (1 October 2026 snapshot). 25 is the count at which the address lookup reports a company cluster.

Places OS Open Names lists for W1W

• Greater London
• London
• City of Westminster
• Islington

Roads filed under W1W

Named roads first, then numbered ones. A road is filed under one district even where it runs through several, so a street missing here may be listed under a neighbouring district — which is why the address lookup never calls a British street absent. Great Britain has no open register of buildings, so a listed road never means a building on it exists.

• Bolsover Street
• Bourlet Close
• Bridford Mews
• Candover Street
• Carburton Street
• Cavendish Mews North
• Cavendish Mews South
• Clipstone Mews
• Clipstone Street
• Devonshire Row Mews
• Foley Street
• Gildea Street
• Gosfield Street
• Grafton Way
• Great Castle Street
• Great Portland Street
• Great Titchfield Street
• Greenwell Street
• Hallam Mews
• Hallam Street
• Hanson Street
• Langham Street
• Little Portland Street
• Little Titchfield Street
• Margaret Court
• Margaret Street
• Market Court
• Market Place
• Marylebone Passage
• Middleton Place
• Mortimer Street
• Nassau Street
• New Cavendish Street
• Ogle Street
• Osnaburgh Street
• Park Crescent Mews East
• Riding House Street
• Winsley Street
• A4201
• B506

Check an address in W1W

Check an address in W1W

The same road list through the API, from the outward code alone:

curl "https://spaw.co/api/v1/address/streets?country=GB&postal_code=W1W" \
  -H "Authorization: Bearer $SPAW_KEY"

Common questions about W1W

What does a W1W postcode tell you?

That the address lies in the W1W district of the W (West London) postcode area, and the place OS Open Names most often lists first for its postcodes is City of Westminster. The district alone does not place a street: the inward half of the full postcode narrows the address to one of the district's 621 live postcodes.

Where the counts come from

• ons-postcode-directory · version 2026-08 · Contains ONS, OS and Royal Mail data © Crown copyright and database right 2026, Open Government Licence v3.0. Northern Ireland postcodes are excluded: their reuse needs a Land & Property Services licence.
• os-open-names · version 2026-11-01 · Contains OS data © Crown copyright and database right 2026, Open Government Licence v3.0.
• uk-companies-house · version 2026-10-01 · Companies House free company data product, Open Government Licence v3.0

What each figure means, and what a district page never says, is set out in Reading a British postcode district page; the glossary defines a postcode district, a postcode area, a postcode directory and a street register.

Data synced on 2026-11-01: the newest version among the datasets listed above.

Districts nearest W1W

• W1T0.3 km
• W1G0.5 km
• W1B0.5 km
• WC1E0.6 km
• W1F0.7 km
• W1C0.8 km
• W1D0.9 km
• W1U0.9 km
• W1S0.9 km
• WC1B1.0 km
• W1K1.1 km
• WC2H1.1 km
• Every district
• How a British address is written
• Check any address

distance between the districts' centroids