SO1 postcode district
SO1, in the SO (Southampton) postcode area, has 0 live and 2,501 terminated postcodes in the ONS Postcode Directory of August 2026, and OS Open Names files no road under it.
| postcode area | SO (Southampton) |
|---|---|
| live postcodes | 0 |
| terminated postcodes | 2,501 |
| sectors | 10 |
| roads listed | 0 |
| companies registered | 41 |
| directory release | 2026-08 |
Postcodes and sectors
0 of the district's 2,501 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 |
|---|---|---|
| SO1 0 | 0 | 227 |
| SO1 1 | 0 | 274 |
| SO1 2 | 0 | 285 |
| SO1 3 | 0 | 276 |
| SO1 4 | 0 | 240 |
| SO1 5 | 0 | 270 |
| SO1 6 | 0 | 278 |
| SO1 7 | 0 | 195 |
| SO1 8 | 0 | 171 |
| SO1 9 | 0 | 285 |
Companies registered in SO1
Companies House lists 41 companies with a registered office in SO1 (1 October 2026 snapshot).
Places OS Open Names lists for SO1
No places have been applied to the district's postcodes on this server yet.
Roads filed under SO1
OS Open Names files no road under SO1, so a street here cannot be confirmed from the register and the lookup answers about the postcode alone.
Check an address in SO1
Common questions about SO1
- What does an SO1 postcode tell you?
- That the address lies in the SO1 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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