SL1 postcode district

Postcodes and sectors

1,654 of the district's 2,879 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 51.51783, -0.62217, which locates the district, not a building.

Companies registered in SL1

Companies House lists 9,303 companies with a registered office in SL1; 1,694 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 SL1

• South East
• Slough
• Buckinghamshire
• Hitchambury
• Rose Hill
• Littleworth Corner

Roads filed under SL1

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.

• Abbey Close
• Abbey Court
• Abbey Park Lane
• Abbotts Way
• Aberdeen Avenue
• Adam Close
• Adelaide Close
• Adelphi Gardens
• Ajax Avenue
• Albert Close
• Albert Street
• Aldborough Spur
• Aldbourne Road
• Alder Close
• Aldin Avenue North
• Aldin Avenue South
• Alexandra Road
• Alice Lane
• Allendale Close
• Almond Road
• Alpha Street North
• Alpha Street South
• Altwood Close
• Amerden Way
• Amesbury Road
• Anslow Place
• Anthony Way
• Arborfield Close
• Argyll Avenue
• Arthur Road
• Ashcroft Court
• Ashmount Crescent
• Aspery Place
• Australia Road
• Autumn Close
• Avebury
• Avon Close
• Aylesbury Crescent
• Bader Gardens
• Baird Close
• Baldwin Road
• Balmoral Close
• Banbury Avenue
• Banks Spur
• Bantry Road
• Barnfield
• Bath Road
• Baxter Close
• Bayley Crescent
• Baylis Road
• Bay Tree Court
• Beckwell Road
• Bedford Avenue
• Beechwood Gardens
• Belfast Avenue
• Belgrave Road
• Bellefield
• Bennetts Close
• Bentley Park
• Bentley Road

Check an address in SL1

Check an address in SL1

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

curl "https://spaw.co/api/v1/address/streets?country=GB&postal_code=SL1" \
  -H "Authorization: Bearer $SPAW_KEY"

Common questions about SL1

What does an SL1 postcode tell you?

That the address lies in the SL1 district of the SL (Slough) postcode area, and the place OS Open Names most often lists first for its postcodes is Slough. The district alone does not place a street: the inward half of the full postcode narrows the address to one of the district's 1,654 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 SL1

• SL22.3 km
• SL44.7 km
• SL35.3 km
• SL606.4 km
• SL07.3 km
• SL67.4 km
• SL89.0 km
• SL910.0 km
• HP910.3 km
• UB810.5 km
• UB710.7 km
• TW1911.1 km
• Every district
• How a British address is written
• Check any address

distance between the districts' centroids