SO40 4 postcode sector in the SO40 district

SO40 4 is a sector of the SO40 district: every postcode that starts SO40 4. It has 143 postcodes in use, 2 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 SO40 4 sector, by flood risk

Map of every postcode in the SO40 4 sector, by flood risk Of the 143 postcodes in the SO40 4 sector that ONS places, 19 have a home or business at high risk, 11 are at medium risk at worst, 14 are at low risk at worst, 2 are at very low risk only and 97 are not on the Environment Agency's at-risk list. 2 groups of postcodes at high or medium risk are outlined: 11 postcodes at high or medium risk; 6 postcodes at high or medium risk. Places named: Marchwood. Drawn over roads, rivers and built-up areas. North is up; the scale bar is 1 km. A326A33A35 SO40 4AE: not on the flood risk listSO40 4AZ: not on the flood risk listSO40 4BF: not on the flood risk listSO40 4BY: not on the flood risk listSO40 4DA: not on the flood risk listSO40 4JW: not on the flood risk listSO40 4JY: not on the flood risk listSO40 4JZ: not on the flood risk listSO40 4PA: not on the flood risk listSO40 4PB: not on the flood risk listSO40 4PD: not on the flood risk listSO40 4SB: not on the flood risk listSO40 4SF: not on the flood risk listSO40 4SG: not on the flood risk listSO40 4SH: not on the flood risk listSO40 4SJ: not on the flood risk listSO40 4SL: not on the flood risk listSO40 4SN: not on the flood risk listSO40 4SR: not on the flood risk listSO40 4SS: not on the flood risk listSO40 4ST: not on the flood risk listSO40 4SU: not on the flood risk listSO40 4SW: not on the flood risk listSO40 4SX: not on the flood risk listSO40 4TE: not on the flood risk listSO40 4TS: not on the flood risk listSO40 4TU: not on the flood risk listSO40 4TW: not on the flood risk listSO40 4UA: not on the flood risk listSO40 4UE: not on the flood risk listSO40 4UF: not on the flood risk listSO40 4UG: not on the flood risk listSO40 4UH: not on the flood risk listSO40 4UJ: not on the flood risk listSO40 4UL: not on the flood risk listSO40 4UN: not on the flood risk listSO40 4UP: not on the flood risk listSO40 4UQ: not on the flood risk listSO40 4US: not on the flood risk listSO40 4UT: not on the flood risk listSO40 4UU: not on the flood risk listSO40 4UW: not on the flood risk listSO40 4UZ: not on the flood risk listSO40 4WA: not on the flood risk listSO40 4WB: not on the flood risk listSO40 4WD: not on the flood risk listSO40 4WE: not on the flood risk listSO40 4WF: not on the flood risk listSO40 4WG: not on the flood risk listSO40 4WJ: not on the flood risk listSO40 4WL: not on the flood risk listSO40 4WN: not on the flood risk listSO40 4WP: not on the flood risk listSO40 4WQ: not on the flood risk listSO40 4WR: not on the flood risk listSO40 4WS: not on the flood risk listSO40 4WX: not on the flood risk listSO40 4WY: not on the flood risk listSO40 4WZ: not on the flood risk listSO40 4XA: not on the flood risk listSO40 4XB: not on the flood risk listSO40 4XD: not on the flood risk listSO40 4XF: not on the flood risk listSO40 4XH: not on the flood risk listSO40 4XJ: not on the flood risk listSO40 4XL: not on the flood risk listSO40 4XN: not on the flood risk listSO40 4XQ: not on the flood risk listSO40 4XW: not on the flood risk listSO40 4XX: not on the flood risk listSO40 4XY: not on the flood risk listSO40 4XZ: not on the flood risk listSO40 4YA: not on the flood risk listSO40 4YB: not on the flood risk listSO40 4YD: not on the flood risk listSO40 4YE: not on the flood risk listSO40 4YF: not on the flood risk listSO40 4YG: not on the flood risk listSO40 4YH: not on the flood risk listSO40 4YJ: not on the flood risk listSO40 4YL: not on the flood risk listSO40 4YN: not on the flood risk listSO40 4YP: not on the flood risk listSO40 4YQ: not on the flood risk listSO40 4YS: not on the flood risk listSO40 4YT: not on the flood risk listSO40 4YU: not on the flood risk listSO40 4YW: not on the flood risk listSO40 4YX: not on the flood risk listSO40 4YY: not on the flood risk listSO40 4YZ: not on the flood risk listSO40 4ZE: not on the flood risk listSO40 4ZG: not on the flood risk listSO40 4ZH: not on the flood risk listSO40 4AA: very low flood risk onlySO40 4AB: very low flood risk onlySO40 4AG: low flood risk at worstSO40 4AJ: low flood risk at worstSO40 4AN: low flood risk at worstSO40 4AP: low flood risk at worstSO40 4AT: low flood risk at worstSO40 4BJ: low flood risk at worstSO40 4JX: low flood risk at worstSO40 4SE: low flood risk at worstSO40 4UB: low flood risk at worstSO40 4WH: low flood risk at worstSO40 4XR: low flood risk at worstSO40 4XT: low flood risk at worstSO40 4XU: low flood risk at worstSO40 4YR: low flood risk at worstSO40 4AD: medium flood risk at worstSO40 4AL: medium flood risk at worstSO40 4AQ: medium flood risk at worstSO40 4AS: medium flood risk at worstSO40 4AW: medium flood risk at worstSO40 4AX: medium flood risk at worstSO40 4BX: medium flood risk at worstSO40 4LE: medium flood risk at worstSO40 4SQ: medium flood risk at worstSO40 4UY: medium flood risk at worstSO40 4WU: medium flood risk at worstSO40 4AF: high flood riskSO40 4AH: high flood riskSO40 4AR: high flood riskSO40 4SY: high flood riskSO40 4BD: high flood riskSO40 4BE: high flood riskSO40 4BL: high flood riskSO40 4LB: high flood riskSO40 4SD: high flood riskSO40 4UD: high flood riskSO40 4UR: high flood riskSO40 4UX: high flood riskSO40 4WT: high flood riskSO40 4WW: high flood riskSO40 4XE: high flood riskSO40 4XG: high flood riskSO40 4XS: high flood riskSO40 4ZD: high flood risk Marchwood 11 postcodes at high or medium risk, outlined: this goes to SO40 4UX, the one with most homes and businesses at high risk11 postcodes at high or medium risk6 postcodes at high or medium risk, outlined: this goes to SO40 4LB, the one with most homes and businesses at high risk6 postcodes at high or medium risk Map of every postcode in the SO40 4 sector, by flood risk Of the 143 postcodes in the SO40 4 sector that ONS places, 19 have a home or business at high risk, 11 are at medium risk at worst, 14 are at low risk at worst, 2 are at very low risk only and 97 are not on the Environment Agency's at-risk list. 2 groups of postcodes at high or medium risk are outlined: 11 postcodes at high or medium risk; 6 postcodes at high or medium risk. Places named: Marchwood. Drawn over roads, rivers and built-up areas. North is up; the scale bar is 1 km. A33 Marchwood
  • A home or business at high risk: 19
  • At medium risk at worst: 11
  • At low risk at worst: 14
  • At very low risk only: 2
  • Not on the at-risk list: 97
  • Outline: where 5 or more postcodes at high or medium risk lie together

Of the 143 postcodes in the SO40 4 sector that ONS places, 19 have a home or business at high risk, 11 are at medium risk at worst, 14 are at low risk at worst, 2 are at very low risk only and 97 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. A dashed outline shows where 5 or more lie within 190 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; 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 high risk

19 postcodes here have a home or business at high risk. These are the 12 with the most homes and businesses at that risk.

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

SO40 4ZD10 at high riskSO40 4UX8 at high riskSO40 4BL6 at high riskSO40 4AU4 at high riskSO40 4UR4 at high riskSO40 4LB4 at high riskSO40 4XG4 at high riskSO40 4WW4 at high riskSO40 4SD3 at high riskSO40 4XS2 at high riskSO40 4AR2 at high riskSO40 4UD2 at high risk

Where the postcodes at high or medium risk lie together

  • 11 postcodes at high or medium risk, outlined on the map. SO40 4UX, is the one with most homes and businesses at high risk.
  • 6 postcodes at high or medium risk, outlined on the map. SO40 4LB, is the one with most homes and businesses at high risk.

What do homes sell for in SO40 4?

Homes in SO40 4 sold for a typical £322,000 in the 12 months to August 2026, across 60 sales, down 4.6% on the 12 months before, HM Land Registry's figures show.

£322,000 typical price, the 12 months to August 2026
£337,500 12 months to August 2025
▼ down 4.6% on the 12 months before
  • Detached £465,000 17 sales
  • Semi-detached £365,000 11 sales
  • Terraced £302,500 18 sales
  • Flat or maisonette £171,475 14 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 SO40 4. 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 SO40 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.

SO40 4AASO40 4ABSO40 4ADSO40 4AESO40 4AFSO40 4AGSO40 4AHSO40 4AJSO40 4ALSO40 4ANSO40 4APSO40 4AQSO40 4ARSO40 4ASSO40 4ATSO40 4AUSO40 4AWSO40 4AXSO40 4AYSO40 4AZSO40 4BDSO40 4BESO40 4BFSO40 4BJSO40 4BLSO40 4BXSO40 4BYSO40 4DASO40 4JUSO40 4JWSO40 4JXSO40 4JYSO40 4JZSO40 4LBSO40 4LESO40 4PASO40 4PBSO40 4PDSO40 4SBSO40 4SDSO40 4SESO40 4SFSO40 4SGSO40 4SHSO40 4SJSO40 4SLSO40 4SNSO40 4SQSO40 4SRSO40 4SSSO40 4STSO40 4SUSO40 4SWSO40 4SXSO40 4SYSO40 4TESO40 4TSSO40 4TUSO40 4TWSO40 4UASO40 4UBSO40 4UDSO40 4UESO40 4UFSO40 4UGSO40 4UHSO40 4UJSO40 4ULSO40 4UNSO40 4UPSO40 4UQSO40 4URSO40 4USSO40 4UTSO40 4UUSO40 4UWSO40 4UXSO40 4UYSO40 4UZSO40 4WASO40 4WBSO40 4WDSO40 4WESO40 4WFSO40 4WGSO40 4WHSO40 4WJSO40 4WLSO40 4WNSO40 4WPSO40 4WQSO40 4WRSO40 4WSSO40 4WTSO40 4WUSO40 4WWSO40 4WXSO40 4WYSO40 4WZSO40 4XASO40 4XBSO40 4XDSO40 4XESO40 4XFSO40 4XGSO40 4XHSO40 4XJSO40 4XLSO40 4XNSO40 4XPSO40 4XQSO40 4XRSO40 4XSSO40 4XTSO40 4XUSO40 4XWSO40 4XXSO40 4XYSO40 4XZSO40 4YASO40 4YBSO40 4YDSO40 4YESO40 4YFSO40 4YGSO40 4YHSO40 4YJSO40 4YLSO40 4YNSO40 4YPSO40 4YQSO40 4YRSO40 4YSSO40 4YTSO40 4YUSO40 4YWSO40 4YXSO40 4YYSO40 4YZSO40 4ZDSO40 4ZESO40 4ZGSO40 4ZH

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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