SO21 1 postcode sector in the SO21 district
SO21 1 is a sector of the SO21 district: every postcode that starts SO21 1. It has 299 postcodes in use, 4 of them large-user postcodes. A large-user postcode is one Royal Mail gives to a single address that gets a lot of mail.
Not sure what a sector is? UK postcode format explained.
Every postcode in the SO21 1 sector, and which are new since 2020
- New since 2020: 11
- In use before 2020: 288
- Outline: where 5 or more new postcodes since 2020 lie together
Of the 299 postcodes in the SO21 1 sector that ONS places, 11 are new since 2020 and 288 were in use before 2020.
Each mark is a postcode's centre point as ONS gives it, not a building. Press one to see its postcode and open its page. New since 2020 means it came into use in January 2020 or later. A dashed outline shows where 5 or more lie within 210 metres of each other. It is not a boundary, and no boundary is drawn. Where marks overlap, the one first in the key is drawn; the counts include every postcode.
Source: Office for National Statistics (ONS) Postcode Directory, August 2026, loaded 20 October 2026, the centre point of each postcode; when each came into use: the same directory; roads, rivers and built-up areas: Contains OS data © Crown copyright and database right 2026. Drawn by us. Street map: Ordnance Survey, OS Open Zoomstack, Open Government Licence v3.0, drawn with MapLibre. How we use them
The 5 newest postcodes
Where the new postcodes lie together
- 6 new postcodes since 2020, outlined on the map. SO21 1GD, is the newest of them.
What do homes sell for in SO21 1?
Homes in SO21 1 sold for a typical £468,250 in the 12 months to August 2026, across 88 sales, down 5.8% on the 12 months before, HM Land Registry's figures show.
- Detached £597,500 30 sales
- Semi-detached £423,000 34 sales
- Terraced £362,500 18 sales
- Flat or maisonette £236,500 6 sales
Each bar is that kind's typical price, against the most expensive kind here.
Standard sales of homes at market value at the postcodes that start SO21 1. A typical price is the median, the middle sale, given from 5 sales or more.
How we work this out: house prices by postcodeSource: HM Land Registry Price Paid Data, files dated 28 September 2026. Contains HM Land Registry data © Crown copyright and database right 2021. This data is licensed under the Open Government Licence v3.0. How we use it
Postcodes in SO21 1
Pick a postcode to see its council and MP, broadband, flood risk, what homes sell for, council tax, the nearest schools and stations, and crime around it.
Source: Office for National Statistics (ONS) Postcode Directory, August 2026, loaded 20 October 2026. Postcodes that have ended are not listed. See all our data sources
Other sectors in SO21
Check a postcode
Something wrong on this page? Report an error and we will check it against the source.