SO18 postcode district

Postcodes and sectors

940 of the district's 1,402 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 50.92417, -1.36198, which locates the district, not a building.

Companies registered in SO18

Companies House lists 1,294 companies with a registered office in SO18; 51 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 SO18

• South East
• Southampton
• City of Southampton
• Eastleigh
• Hampshire
• West End

Roads filed under SO18

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.

• Aberdour Close
• Adur Close
• Alfred Rose Court
• Almatade Road
• Alpine Close
• Alum Way
• Angel Crescent
• Appleton Road
• April Close
• Arden Close
• Arun Road
• Ash Tree Road
• Atlantic Park View
• Avon Road
• Bailey Green
• Balaclava Road
• Bank Side
• Barle Close
• Barnes Close
• Barton Crescent
• Beauworth Avenue
• Beech Avenue
• Beechwood Gardens
• Beechwood Rise
• Benhams Farm Close
• Benhams Road
• Bentley Green
• Beverley Heights
• Bitterne Park Triangle
• Bitterne Road
• Bitterne Road East
• Bitterne Road West
• Blendworth Lane
• Bond Road
• Bramble Mews
• Bramdean Road
• Breamore Road
• Brentwood Crescent
• Broadwater Road
• Bromley Road
• Brook Road
• Brookside Way
• Bullar Road
• Burnett Close
• Burnham Chase
• Camelia Gardens
• Candy Lane
• Capon Close
• Carpathia Close
• Castle Road
• Cerne Close
• Chafen Road
• Chalk Hill
• Chawton Close
• Cheriton Avenue
• Chester Road
• Chichester Road
• Chilcomb Road
• Clanfield Road
• Clark Mews

Check an address in SO18

Check an address in SO18

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

curl "https://spaw.co/api/v1/address/streets?country=GB&postal_code=SO18" \
  -H "Authorization: Bearer $SPAW_KEY"

Common questions about SO18

What does an SO18 postcode tell you?

That the address lies in the SO18 district of the SO (Southampton) postcode area, and the place OS Open Names most often lists first for its postcodes is Southampton. The district alone does not place a street: the inward half of the full postcode narrows the address to one of the district's 940 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 SO18

• SO172.2 km
• SO192.5 km
• SO143.1 km
• SO304.2 km
• SO154.4 km
• SO165.2 km
• SO505.2 km
• SO537.0 km
• SO317.4 km
• SO528.3 km
• SO458.9 km
• SO4010.0 km
• Every district
• How a British address is written
• Check any address

distance between the districts' centroids