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SO4 postcode district

SO4, in the SO (Southampton) postcode area, has 0 live and 3,223 terminated postcodes in the ONS Postcode Directory of August 2026, and OS Open Names files no road under it.

postcode areaSO (Southampton)
live postcodes0
terminated postcodes3,223
sectors10
roads listed0
companies registered15
directory release2026-08

Postcodes and sectors

0 of the district's 3,223 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.

sector live terminated
SO4 00344
SO4 10357
SO4 20309
SO4 30383
SO4 40283
SO4 50336
SO4 60325
SO4 70297
SO4 80259
SO4 90330

Companies registered in SO4

Companies House lists 15 companies with a registered office in SO4 (1 October 2026 snapshot).

Places OS Open Names lists for SO4

No places have been applied to the district's postcodes on this server yet.

Roads filed under SO4

OS Open Names files no road under SO4, so a street here cannot be confirmed from the register and the lookup answers about the postcode alone.

Check an address in SO4

Check an address in SO4

Common questions about SO4

What does an SO4 postcode tell you?
That the address lies in the SO4 district of the SO (Southampton) postcode area. The district alone does not place a street, and none of its postcodes is live in the ONS Postcode Directory of August 2026.

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.

Other districts in SO

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