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SO3 postcode district

SO3, in the SO (Southampton) postcode area, has 0 live and 2,273 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 postcodes2,273
sectors9
roads listed0
companies registered17
directory release2026-08

Postcodes and sectors

0 of the district's 2,273 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
SO3 10288
SO3 20320
SO3 30262
SO3 40369
SO3 50260
SO3 60396
SO3 70109
SO3 80128
SO3 90141

Companies registered in SO3

Companies House lists 17 companies with a registered office in SO3 (1 October 2026 snapshot).

Places OS Open Names lists for SO3

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

Roads filed under SO3

OS Open Names files no road under SO3, so a street here cannot be confirmed from the register and the lookup answers about the postcode alone.

Check an address in SO3

Check an address in SO3

Common questions about SO3

What does an SO3 postcode tell you?
That the address lies in the SO3 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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