SO17 3 postcode sector in the SO17 district

SO17 3 is a sector of the SO17 district: every postcode that starts SO17 3. It has 74 postcodes in use, one of them a large-user postcode. 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 SO17 3 sector, by flood risk

Map of every postcode in the SO17 3 sector, by flood risk Of the 74 postcodes in the SO17 3 sector that ONS places, 1 are at medium risk at worst and 73 are not on the Environment Agency's at-risk list. One postcode lies beyond the edge and is listed under the map. Places named: Swaythling. Drawn over roads, rivers and built-up areas. North is up; the scale bar is 250 m. A335 SO17 3AA: not on the flood risk listSO17 3AB: not on the flood risk listSO17 3AD: not on the flood risk listSO17 3AE: not on the flood risk listSO17 3AF: not on the flood risk listSO17 3AG: not on the flood risk listSO17 3AH: not on the flood risk listSO17 3AJ: not on the flood risk listSO17 3AP: not on the flood risk listSO17 3AQ: not on the flood risk listSO17 3AR: not on the flood risk listSO17 3AS: not on the flood risk listSO17 3AT: not on the flood risk listSO17 3AU: not on the flood risk listSO17 3AW: not on the flood risk listSO17 3AX: not on the flood risk listSO17 3BD: not on the flood risk listSO17 3EA: not on the flood risk listSO17 3ED: not on the flood risk listSO17 3ES: not on the flood risk listSO17 3QY: not on the flood risk listSO17 3QZ: not on the flood risk listSO17 3RA: not on the flood risk listSO17 3RB: not on the flood risk listSO17 3RD: not on the flood risk listSO17 3RE: not on the flood risk listSO17 3RF: not on the flood risk listSO17 3RG: not on the flood risk listSO17 3RH: not on the flood risk listSO17 3RJ: not on the flood risk listSO17 3RL: not on the flood risk listSO17 3RN: not on the flood risk listSO17 3RP: not on the flood risk listSO17 3RQ: not on the flood risk listSO17 3RS: not on the flood risk listSO17 3RT: not on the flood risk listSO17 3RU: not on the flood risk listSO17 3RW: not on the flood risk listSO17 3RX: not on the flood risk listSO17 3RY: not on the flood risk listSO17 3RZ: not on the flood risk listSO17 3SA: not on the flood risk listSO17 3SB: not on the flood risk listSO17 3SD: not on the flood risk listSO17 3SE: not on the flood risk listSO17 3SF: not on the flood risk listSO17 3SG: not on the flood risk listSO17 3SH: not on the flood risk listSO17 3SJ: not on the flood risk listSO17 3SL: not on the flood risk listSO17 3SN: not on the flood risk listSO17 3SP: not on the flood risk listSO17 3SQ: not on the flood risk listSO17 3SS: not on the flood risk listSO17 3ST: not on the flood risk listSO17 3SU: not on the flood risk listSO17 3SW: not on the flood risk listSO17 3SX: not on the flood risk listSO17 3SY: not on the flood risk listSO17 3SZ: not on the flood risk listSO17 3TA: not on the flood risk listSO17 3TB: not on the flood risk listSO17 3TD: not on the flood risk listSO17 3TE: not on the flood risk listSO17 3TF: not on the flood risk listSO17 3TG: not on the flood risk listSO17 3TH: not on the flood risk listSO17 3TJ: not on the flood risk listSO17 3TL: not on the flood risk listSO17 3TN: not on the flood risk listSO17 3TW: not on the flood risk listSO17 3UA: not on the flood risk listSO17 3AN: medium flood risk at worst Swaythling Map of every postcode in the SO17 3 sector, by flood risk Of the 74 postcodes in the SO17 3 sector that ONS places, 1 are at medium risk at worst and 73 are not on the Environment Agency's at-risk list. One postcode lies beyond the edge and is listed under the map. Places named: Swaythling. Drawn over roads, rivers and built-up areas. North is up; the scale bar is 250 m. Swaythling
  • A home or business at high risk: 0
  • At medium risk at worst: 1
  • At low risk at worst: 0
  • At very low risk only: 0
  • Not on the at-risk list: 73

Of the 74 postcodes in the SO17 3 sector that ONS places, 1 are at medium risk at worst and 73 are not on the Environment Agency's at-risk list.

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. 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; flood risk: Environment Agency, published 6 July 2026; 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 postcodes at medium risk at worst

Beside each: how many of its homes and businesses the Environment Agency puts at that risk.

SO17 3AN1 at medium risk

Further out, not drawn

This postcode lies well apart from the rest, so the map is drawn without it to show the rest closer; it is in every count.

SO17 3WF

What do homes sell for in SO17 3?

Homes in SO17 3 sold for a typical £295,000 in the 12 months to August 2026, across 17 sales, down 3.9% on the 12 months before, HM Land Registry's figures show.

£295,000 typical price, the 12 months to August 2026
£307,000 12 months to August 2025
▼ down 3.9% on the 12 months before
  • Semi-detached £320,000 12 sales
  • Terraced 3 sales, too few to price
  • Flat or maisonette 2 sales, too few to price

Standard sales of homes at market value at the postcodes that start SO17 3. A typical price is the median, the middle sale, given from 5 sales or more.

How we work this out: house prices by postcode

Source: 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 SO17 3

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.

SO17 3AASO17 3ABSO17 3ADSO17 3AESO17 3AFSO17 3AGSO17 3AHSO17 3AJSO17 3ANSO17 3APSO17 3AQSO17 3ARSO17 3ASSO17 3ATSO17 3AUSO17 3AWSO17 3AXSO17 3BDSO17 3EASO17 3EDSO17 3ESSO17 3QYSO17 3QZSO17 3RASO17 3RBSO17 3RDSO17 3RESO17 3RFSO17 3RGSO17 3RHSO17 3RJSO17 3RLSO17 3RNSO17 3RPSO17 3RQSO17 3RSSO17 3RTSO17 3RUSO17 3RWSO17 3RXSO17 3RYSO17 3RZSO17 3SASO17 3SBSO17 3SDSO17 3SESO17 3SFSO17 3SGSO17 3SHSO17 3SJSO17 3SLSO17 3SNSO17 3SPSO17 3SQSO17 3SSSO17 3STSO17 3SUSO17 3SWSO17 3SXSO17 3SYSO17 3SZSO17 3TASO17 3TBSO17 3TDSO17 3TESO17 3TFSO17 3TGSO17 3THSO17 3TJSO17 3TLSO17 3TNSO17 3TWSO17 3UASO17 3WF

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

What council am I in? The council, borough or local authority for a postcode, and the county council where there is one. What ward am I in? The ward for a postcode, with its council, constituency and parish.

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