GU21 4 postcode sector in the GU21 district

GU21 4 is a sector of the GU21 district: every postcode that starts GU21 4. It has 259 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 GU21 4 sector, by flood risk

Map of every postcode in the GU21 4 sector, by flood risk Of the 259 postcodes in the GU21 4 sector that ONS places, 3 have a home or business at high risk, 1 are at low risk at worst and 255 are not on the Environment Agency's at-risk list. One postcode lies beyond the edge and is listed under the map. Places named: Horsell. Drawn over roads, rivers and built-up areas. North is up; the scale bar is 500 m. A320A3046A245 GU21 4AA: not on the flood risk listGU21 4AB: not on the flood risk listGU21 4AE: not on the flood risk listGU21 4AF: not on the flood risk listGU21 4AG: not on the flood risk listGU21 4AJ: not on the flood risk listGU21 4AL: not on the flood risk listGU21 4AN: not on the flood risk listGU21 4AP: not on the flood risk listGU21 4AQ: not on the flood risk listGU21 4AS: not on the flood risk listGU21 4AT: not on the flood risk listGU21 4AU: not on the flood risk listGU21 4AW: not on the flood risk listGU21 4AX: not on the flood risk listGU21 4AY: not on the flood risk listGU21 4AZ: not on the flood risk listGU21 4BA: not on the flood risk listGU21 4BB: not on the flood risk listGU21 4BD: not on the flood risk listGU21 4BE: not on the flood risk listGU21 4BF: not on the flood risk listGU21 4BG: not on the flood risk listGU21 4BH: not on the flood risk listGU21 4BJ: not on the flood risk listGU21 4BL: not on the flood risk listGU21 4BN: not on the flood risk listGU21 4BP: not on the flood risk listGU21 4BS: not on the flood risk listGU21 4BT: not on the flood risk listGU21 4BU: not on the flood risk listGU21 4BW: not on the flood risk listGU21 4BX: not on the flood risk listGU21 4BY: not on the flood risk listGU21 4BZ: not on the flood risk listGU21 4DA: not on the flood risk listGU21 4DB: not on the flood risk listGU21 4DD: not on the flood risk listGU21 4DE: not on the flood risk listGU21 4DH: not on the flood risk listGU21 4DJ: not on the flood risk listGU21 4DL: not on the flood risk listGU21 4DN: not on the flood risk listGU21 4DP: not on the flood risk listGU21 4DR: not on the flood risk listGU21 4DS: not on the flood risk listGU21 4DT: not on the flood risk listGU21 4DU: not on the flood risk listGU21 4DW: not on the flood risk listGU21 4DX: not on the flood risk listGU21 4DY: not on the flood risk listGU21 4DZ: not on the flood risk listGU21 4ED: not on the flood risk listGU21 4EE: not on the flood risk listGU21 4EF: not on the flood risk listGU21 4EH: not on the flood risk listGU21 4EL: not on the flood risk listGU21 4EN: not on the flood risk listGU21 4EQ: not on the flood risk listGU21 4ER: not on the flood risk listGU21 4ES: not on the flood risk listGU21 4ET: not on the flood risk listGU21 4EU: not on the flood risk listGU21 4EW: not on the flood risk listGU21 4EX: not on the flood risk listGU21 4HA: not on the flood risk listGU21 4HE: not on the flood risk listGU21 4HG: not on the flood risk listGU21 4HH: not on the flood risk listGU21 4HJ: not on the flood risk listGU21 4HL: not on the flood risk listGU21 4HN: not on the flood risk listGU21 4HP: not on the flood risk listGU21 4HQ: not on the flood risk listGU21 4HT: not on the flood risk listGU21 4HW: not on the flood risk listGU21 4HX: not on the flood risk listGU21 4HY: not on the flood risk listGU21 4HZ: not on the flood risk listGU21 4JA: not on the flood risk listGU21 4JB: not on the flood risk listGU21 4JD: not on the flood risk listGU21 4JE: not on the flood risk listGU21 4JF: not on the flood risk listGU21 4JG: not on the flood risk listGU21 4JH: not on the flood risk listGU21 4JJ: not on the flood risk listGU21 4JL: not on the flood risk listGU21 4JN: not on the flood risk listGU21 4JP: not on the flood risk listGU21 4JQ: not on the flood risk listGU21 4JR: not on the flood risk listGU21 4JS: not on the flood risk listGU21 4JT: not on the flood risk listGU21 4JU: not on the flood risk listGU21 4JW: not on the flood risk listGU21 4JX: not on the flood risk listGU21 4JZ: not on the flood risk listGU21 4LB: not on the flood risk listGU21 4LH: not on the flood risk listGU21 4LJ: not on the flood risk listGU21 4LL: not on the flood risk listGU21 4LN: not on the flood risk listGU21 4LP: not on the flood risk listGU21 4LQ: not on the flood risk listGU21 4LR: not on the flood risk listGU21 4LS: not on the flood risk listGU21 4LT: not on the flood risk listGU21 4LU: not on the flood risk listGU21 4LW: not on the flood risk listGU21 4LX: not on the flood risk listGU21 4LY: not on the flood risk listGU21 4LZ: not on the flood risk listGU21 4NA: not on the flood risk listGU21 4NB: not on the flood risk listGU21 4ND: not on the flood risk listGU21 4NH: not on the flood risk listGU21 4NJ: not on the flood risk listGU21 4NN: not on the flood risk listGU21 4NQ: not on the flood risk listGU21 4NR: not on the flood risk listGU21 4NS: not on the flood risk listGU21 4NT: not on the flood risk listGU21 4NU: not on the flood risk listGU21 4NW: not on the flood risk listGU21 4NX: not on the flood risk listGU21 4PA: not on the flood risk listGU21 4PB: not on the flood risk listGU21 4PD: not on the flood risk listGU21 4PE: not on the flood risk listGU21 4PF: not on the flood risk listGU21 4PG: not on the flood risk listGU21 4PH: not on the flood risk listGU21 4PJ: not on the flood risk listGU21 4PL: not on the flood risk listGU21 4PN: not on the flood risk listGU21 4PP: not on the flood risk listGU21 4PQ: not on the flood risk listGU21 4PR: not on the flood risk listGU21 4PS: not on the flood risk listGU21 4PT: not on the flood risk listGU21 4PW: not on the flood risk listGU21 4PY: not on the flood risk listGU21 4PZ: not on the flood risk listGU21 4QA: not on the flood risk listGU21 4QD: not on the flood risk listGU21 4QE: not on the flood risk listGU21 4QF: not on the flood risk listGU21 4QG: not on the flood risk listGU21 4QH: not on the flood risk listGU21 4QJ: not on the flood risk listGU21 4QL: not on the flood risk listGU21 4QN: not on the flood risk listGU21 4QP: not on the flood risk listGU21 4QQ: not on the flood risk listGU21 4QR: not on the flood risk listGU21 4QS: not on the flood risk listGU21 4QT: not on the flood risk listGU21 4QU: not on the flood risk listGU21 4QW: not on the flood risk listGU21 4QX: not on the flood risk listGU21 4QY: not on the flood risk listGU21 4QZ: not on the flood risk listGU21 4RA: not on the flood risk listGU21 4RB: not on the flood risk listGU21 4RD: not on the flood risk listGU21 4RE: not on the flood risk listGU21 4RF: not on the flood risk listGU21 4RG: not on the flood risk listGU21 4RH: not on the flood risk listGU21 4RJ: not on the flood risk listGU21 4RL: not on the flood risk listGU21 4RN: not on the flood risk listGU21 4RP: not on the flood risk listGU21 4RR: not on the flood risk listGU21 4RS: not on the flood risk listGU21 4RT: not on the flood risk listGU21 4RU: not on the flood risk listGU21 4RW: not on the flood risk listGU21 4RX: not on the flood risk listGU21 4RY: not on the flood risk listGU21 4RZ: not on the flood risk listGU21 4SB: not on the flood risk listGU21 4SD: not on the flood risk listGU21 4SE: not on the flood risk listGU21 4SF: not on the flood risk listGU21 4SG: not on the flood risk listGU21 4SH: not on the flood risk listGU21 4SJ: not on the flood risk listGU21 4SL: not on the flood risk listGU21 4SQ: not on the flood risk listGU21 4SS: not on the flood risk listGU21 4ST: not on the flood risk listGU21 4SU: not on the flood risk listGU21 4SY: not on the flood risk listGU21 4SZ: not on the flood risk listGU21 4TA: not on the flood risk listGU21 4TB: not on the flood risk listGU21 4TD: not on the flood risk listGU21 4TE: not on the flood risk listGU21 4TF: not on the flood risk listGU21 4TG: not on the flood risk listGU21 4TH: not on the flood risk listGU21 4TJ: not on the flood risk listGU21 4TL: not on the flood risk listGU21 4TN: not on the flood risk listGU21 4TP: not on the flood risk listGU21 4TQ: not on the flood risk listGU21 4TW: not on the flood risk listGU21 4UA: not on the flood risk listGU21 4UB: not on the flood risk listGU21 4UD: not on the flood risk listGU21 4UE: not on the flood risk listGU21 4UF: not on the flood risk listGU21 4UG: not on the flood risk listGU21 4UJ: not on the flood risk listGU21 4UL: not on the flood risk listGU21 4UN: not on the flood risk listGU21 4UP: not on the flood risk listGU21 4UQ: not on the flood risk listGU21 4UR: not on the flood risk listGU21 4US: not on the flood risk listGU21 4UT: not on the flood risk listGU21 4UU: not on the flood risk listGU21 4UW: not on the flood risk listGU21 4UX: not on the flood risk listGU21 4UY: not on the flood risk listGU21 4XA: not on the flood risk listGU21 4XB: not on the flood risk listGU21 4XD: not on the flood risk listGU21 4XE: not on the flood risk listGU21 4XF: not on the flood risk listGU21 4XG: not on the flood risk listGU21 4XH: not on the flood risk listGU21 4XP: not on the flood risk listGU21 4XQ: not on the flood risk listGU21 4XR: not on the flood risk listGU21 4XU: not on the flood risk listGU21 4XY: not on the flood risk listGU21 4XZ: not on the flood risk listGU21 4YA: not on the flood risk listGU21 4YD: not on the flood risk listGU21 4YE: not on the flood risk listGU21 4YF: not on the flood risk listGU21 4YL: not on the flood risk listGU21 4YP: not on the flood risk listGU21 4YQ: not on the flood risk listGU21 4YR: not on the flood risk listGU21 4ZA: not on the flood risk listGU21 4YB: low flood risk at worstGU21 4XS: high flood riskGU21 4XX: high flood riskGU21 4YH: high flood risk Horsell Map of every postcode in the GU21 4 sector, by flood risk Of the 259 postcodes in the GU21 4 sector that ONS places, 3 have a home or business at high risk, 1 are at low risk at worst and 255 are not on the Environment Agency's at-risk list. One postcode lies beyond the edge and is listed under the map. Places named: Horsell. Drawn over roads, rivers and built-up areas. North is up; the scale bar is 1 km. A3046 Horsell
  • A home or business at high risk: 3
  • At medium risk at worst: 0
  • At low risk at worst: 1
  • At very low risk only: 0
  • Not on the at-risk list: 255

Of the 259 postcodes in the GU21 4 sector that ONS places, 3 have a home or business at high risk, 1 are at low risk at worst and 255 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 high risk

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

GU21 4XS1 at high riskGU21 4XX1 at high riskGU21 4YH1 at high 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.

GU21 4XT

What do homes sell for in GU21 4?

Homes in GU21 4 sold for a typical £725,000 in the 12 months to August 2026, across 111 sales, down 4.9% on the 12 months before, HM Land Registry's figures show.

£725,000 typical price, the 12 months to August 2026
£762,250 12 months to August 2025
▼ down 4.9% on the 12 months before
  • Detached £880,000 59 sales
  • Semi-detached £575,000 32 sales
  • Terraced £560,000 11 sales
  • Flat or maisonette £310,000 9 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 GU21 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 GU21 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.

GU21 4AAGU21 4ABGU21 4AEGU21 4AFGU21 4AGGU21 4AJGU21 4ALGU21 4ANGU21 4APGU21 4AQGU21 4ASGU21 4ATGU21 4AUGU21 4AWGU21 4AXGU21 4AYGU21 4AZGU21 4BAGU21 4BBGU21 4BDGU21 4BEGU21 4BFGU21 4BGGU21 4BHGU21 4BJGU21 4BLGU21 4BNGU21 4BPGU21 4BSGU21 4BTGU21 4BUGU21 4BWGU21 4BXGU21 4BYGU21 4BZGU21 4DAGU21 4DBGU21 4DDGU21 4DEGU21 4DHGU21 4DJGU21 4DLGU21 4DNGU21 4DPGU21 4DRGU21 4DSGU21 4DTGU21 4DUGU21 4DWGU21 4DXGU21 4DYGU21 4DZGU21 4EDGU21 4EEGU21 4EFGU21 4EHGU21 4ELGU21 4ENGU21 4EQGU21 4ERGU21 4ESGU21 4ETGU21 4EUGU21 4EWGU21 4EXGU21 4HAGU21 4HEGU21 4HGGU21 4HHGU21 4HJGU21 4HLGU21 4HNGU21 4HPGU21 4HQGU21 4HTGU21 4HWGU21 4HXGU21 4HYGU21 4HZGU21 4JAGU21 4JBGU21 4JDGU21 4JEGU21 4JFGU21 4JGGU21 4JHGU21 4JJGU21 4JLGU21 4JNGU21 4JPGU21 4JQGU21 4JRGU21 4JSGU21 4JTGU21 4JUGU21 4JWGU21 4JXGU21 4JYGU21 4JZGU21 4LAGU21 4LBGU21 4LDGU21 4LHGU21 4LJGU21 4LLGU21 4LNGU21 4LPGU21 4LQGU21 4LRGU21 4LSGU21 4LTGU21 4LUGU21 4LWGU21 4LXGU21 4LYGU21 4LZGU21 4NAGU21 4NBGU21 4NDGU21 4NHGU21 4NJGU21 4NNGU21 4NQGU21 4NRGU21 4NSGU21 4NTGU21 4NUGU21 4NWGU21 4NXGU21 4PAGU21 4PBGU21 4PDGU21 4PEGU21 4PFGU21 4PGGU21 4PHGU21 4PJGU21 4PLGU21 4PNGU21 4PPGU21 4PQGU21 4PRGU21 4PSGU21 4PTGU21 4PWGU21 4PYGU21 4PZGU21 4QAGU21 4QDGU21 4QEGU21 4QFGU21 4QGGU21 4QHGU21 4QJGU21 4QLGU21 4QNGU21 4QPGU21 4QQGU21 4QRGU21 4QSGU21 4QTGU21 4QUGU21 4QWGU21 4QXGU21 4QYGU21 4QZGU21 4RAGU21 4RBGU21 4RDGU21 4REGU21 4RFGU21 4RGGU21 4RHGU21 4RJGU21 4RLGU21 4RNGU21 4RPGU21 4RRGU21 4RSGU21 4RTGU21 4RUGU21 4RWGU21 4RXGU21 4RYGU21 4RZGU21 4SBGU21 4SDGU21 4SEGU21 4SFGU21 4SGGU21 4SHGU21 4SJGU21 4SLGU21 4SQGU21 4SSGU21 4STGU21 4SUGU21 4SXGU21 4SYGU21 4SZGU21 4TAGU21 4TBGU21 4TDGU21 4TEGU21 4TFGU21 4TGGU21 4THGU21 4TJGU21 4TLGU21 4TNGU21 4TPGU21 4TQGU21 4TWGU21 4UAGU21 4UBGU21 4UDGU21 4UEGU21 4UFGU21 4UGGU21 4UJGU21 4ULGU21 4UNGU21 4UPGU21 4UQGU21 4URGU21 4USGU21 4UTGU21 4UUGU21 4UWGU21 4UXGU21 4UYGU21 4XAGU21 4XBGU21 4XDGU21 4XEGU21 4XFGU21 4XGGU21 4XHGU21 4XPGU21 4XQGU21 4XRGU21 4XSGU21 4XTGU21 4XUGU21 4XXGU21 4XYGU21 4XZGU21 4YAGU21 4YBGU21 4YDGU21 4YEGU21 4YFGU21 4YGGU21 4YHGU21 4YLGU21 4YPGU21 4YQGU21 4YRGU21 4ZA

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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