SW1Y postcode district

Postcodes and sectors

183 of the district's 682 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 51.50763, -0.13454, which locates the district, not a building.

Companies registered in SW1Y

Companies House lists 5,249 companies with a registered office in SW1Y; 3,584 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 SW1Y

• Greater London
• London
• City of Westminster
• Wandsworth

Roads filed under SW1Y

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.

• Angel Court
• Apple Tree Yard
• Babmaes Street
• Bury Street
• Carlton Gardens
• Carlton House Terrace
• Carlton Street
• Charles Ii Street
• Church Place
• Cleveland Place
• Cockspur Court
• Cockspur Street
• Crown Passage
• Duke of York Street
• Duke Street St James's
• Embassy Boulevard
• Haymarket
• Jermyn Street
• King Street
• Masons Yard
• Norris Street
• Ormond Yard
• Oxendon Street
• Pall Mall
• Pall Mall East
• Pall Mall Place
• Panton Street
• Princes Arcade
• Rose and Crown Yard
• Royal Opera Arcade
• Ryder Street
• Ryder Yard
• Shavers Place
• St Alban's Street
• St James's Market
• St James's Square
• Suffolk Place
• Suffolk Street
• The Mall
• Trafalgar Square
• Warwick House Street
• Waterloo Place
• A4
• B327

Check an address in SW1Y

Check an address in SW1Y

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

curl "https://spaw.co/api/v1/address/streets?country=GB&postal_code=SW1Y" \
  -H "Authorization: Bearer $SPAW_KEY"

Common questions about SW1Y

What does an SW1Y postcode tell you?

That the address lies in the SW1Y district of the SW (South 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 183 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 SW1Y

• SW1A0.4 km
• W1D0.6 km
• W1F0.7 km
• W1S0.7 km
• WC2N0.7 km
• W1J0.7 km
• WC2H0.8 km
• W1B0.9 km
• WC2E0.9 km
• SW1H1.0 km
• SW1E1.1 km
• W1K1.2 km
• Every district
• How a British address is written
• Check any address

distance between the districts' centroids