SN3 4 postcode sector in the SN3 district
SN3 4 is a sector of the SN3 district: every postcode that starts SN3 4. It has 332 postcodes in use, 7 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 SN3 4 sector, and which are new since 2020
- New since 2020: 21
- In use before 2020: 311
- Outline: where 5 or more new postcodes since 2020 lie together
Of the 332 postcodes in the SN3 4 sector that ONS places, 21 are new since 2020 and 311 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 160 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. Names in italics are council wards: we hold no town or village names here.
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
2 further out, not drawn
These postcodes lie well apart from the rest, so the map is drawn without them to show the rest closer; they are in every count.
What do homes sell for in SN3 4?
Homes in SN3 4 sold for a typical £300,000 in the 12 months to August 2026, across 178 sales, no change on the 12 months before, HM Land Registry's figures show.
- Detached £422,500 32 sales
- Semi-detached £310,000 80 sales
- Terraced £280,000 43 sales
- Flat or maisonette £143,000 23 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 SN3 4. 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 SN3 4
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 SN3
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