AL5 4 postcode sector in the AL5 district

AL5 4 is a sector of the AL5 district: every postcode that starts AL5 4. It has 252 postcodes in use, 12 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 AL5 4 sector, by flood risk

Map of every postcode in the AL5 4 sector, by flood risk Of the 252 postcodes in the AL5 4 sector that ONS places, 1 have a home or business at high risk, 1 are at low risk at worst, 2 are at very low risk only and 248 are not on the Environment Agency's at-risk list. One postcode lies beyond the edge and is listed under the map. Places named: Harpenden. Drawn over roads, rivers and built-up areas. North is up; the scale bar is 250 m. AL5 4AA: not on the flood risk listAL5 4AB: not on the flood risk listAL5 4AD: not on the flood risk listAL5 4AE: not on the flood risk listAL5 4AF: not on the flood risk listAL5 4AG: not on the flood risk listAL5 4AH: not on the flood risk listAL5 4AJ: not on the flood risk listAL5 4AL: not on the flood risk listAL5 4AN: not on the flood risk listAL5 4AP: not on the flood risk listAL5 4AQ: not on the flood risk listAL5 4AR: not on the flood risk listAL5 4AS: not on the flood risk listAL5 4AT: not on the flood risk listAL5 4AU: not on the flood risk listAL5 4AW: not on the flood risk listAL5 4AX: not on the flood risk listAL5 4AY: not on the flood risk listAL5 4BA: not on the flood risk listAL5 4BB: not on the flood risk listAL5 4BD: not on the flood risk listAL5 4BE: not on the flood risk listAL5 4BG: not on the flood risk listAL5 4BH: not on the flood risk listAL5 4BJ: not on the flood risk listAL5 4BP: not on the flood risk listAL5 4BQ: not on the flood risk listAL5 4BS: not on the flood risk listAL5 4BT: not on the flood risk listAL5 4BU: not on the flood risk listAL5 4BW: not on the flood risk listAL5 4BX: not on the flood risk listAL5 4BZ: not on the flood risk listAL5 4DB: not on the flood risk listAL5 4DD: not on the flood risk listAL5 4DE: not on the flood risk listAL5 4DF: not on the flood risk listAL5 4DG: not on the flood risk listAL5 4DH: not on the flood risk listAL5 4DJ: not on the flood risk listAL5 4DN: not on the flood risk listAL5 4DQ: not on the flood risk listAL5 4DU: not on the flood risk listAL5 4DZ: not on the flood risk listAL5 4EA: not on the flood risk listAL5 4EB: not on the flood risk listAL5 4ED: not on the flood risk listAL5 4EE: not on the flood risk listAL5 4EF: not on the flood risk listAL5 4EG: not on the flood risk listAL5 4EL: not on the flood risk listAL5 4EP: not on the flood risk listAL5 4EQ: not on the flood risk listAL5 4ES: not on the flood risk listAL5 4ET: not on the flood risk listAL5 4EU: not on the flood risk listAL5 4EW: not on the flood risk listAL5 4EX: not on the flood risk listAL5 4EY: not on the flood risk listAL5 4EZ: not on the flood risk listAL5 4FB: not on the flood risk listAL5 4FE: not on the flood risk listAL5 4FF: not on the flood risk listAL5 4FG: not on the flood risk listAL5 4FH: not on the flood risk listAL5 4FJ: not on the flood risk listAL5 4FL: not on the flood risk listAL5 4FN: not on the flood risk listAL5 4FP: not on the flood risk listAL5 4FQ: not on the flood risk listAL5 4FR: not on the flood risk listAL5 4FS: not on the flood risk listAL5 4FU: not on the flood risk listAL5 4FW: not on the flood risk listAL5 4FX: not on the flood risk listAL5 4GA: not on the flood risk listAL5 4GB: not on the flood risk listAL5 4GJ: not on the flood risk listAL5 4GW: not on the flood risk listAL5 4GX: not on the flood risk listAL5 4GZ: not on the flood risk listAL5 4HA: not on the flood risk listAL5 4HB: not on the flood risk listAL5 4HD: not on the flood risk listAL5 4HE: not on the flood risk listAL5 4HF: not on the flood risk listAL5 4HG: not on the flood risk listAL5 4HH: not on the flood risk listAL5 4HJ: not on the flood risk listAL5 4HL: not on the flood risk listAL5 4HN: not on the flood risk listAL5 4HP: not on the flood risk listAL5 4HQ: not on the flood risk listAL5 4HR: not on the flood risk listAL5 4HS: not on the flood risk listAL5 4HT: not on the flood risk listAL5 4HW: not on the flood risk listAL5 4HX: not on the flood risk listAL5 4HY: not on the flood risk listAL5 4JA: not on the flood risk listAL5 4JB: not on the flood risk listAL5 4JD: not on the flood risk listAL5 4JE: not on the flood risk listAL5 4JF: not on the flood risk listAL5 4JN: not on the flood risk listAL5 4JP: not on the flood risk listAL5 4JR: not on the flood risk listAL5 4JS: not on the flood risk listAL5 4JT: not on the flood risk listAL5 4JU: not on the flood risk listAL5 4JW: not on the flood risk listAL5 4JX: not on the flood risk listAL5 4JY: not on the flood risk listAL5 4JZ: not on the flood risk listAL5 4LA: not on the flood risk listAL5 4LB: not on the flood risk listAL5 4LD: not on the flood risk listAL5 4LE: not on the flood risk listAL5 4LF: not on the flood risk listAL5 4LG: not on the flood risk listAL5 4LH: not on the flood risk listAL5 4LJ: not on the flood risk listAL5 4LL: not on the flood risk listAL5 4LN: not on the flood risk listAL5 4LP: not on the flood risk listAL5 4LQ: not on the flood risk listAL5 4LR: not on the flood risk listAL5 4LS: not on the flood risk listAL5 4LT: not on the flood risk listAL5 4LU: not on the flood risk listAL5 4LW: not on the flood risk listAL5 4LX: not on the flood risk listAL5 4LY: not on the flood risk listAL5 4LZ: not on the flood risk listAL5 4NA: not on the flood risk listAL5 4NB: not on the flood risk listAL5 4ND: not on the flood risk listAL5 4NF: not on the flood risk listAL5 4NG: not on the flood risk listAL5 4NL: not on the flood risk listAL5 4NS: not on the flood risk listAL5 4NT: not on the flood risk listAL5 4NX: not on the flood risk listAL5 4NY: not on the flood risk listAL5 4NZ: not on the flood risk listAL5 4PA: not on the flood risk listAL5 4PB: not on the flood risk listAL5 4PD: not on the flood risk listAL5 4PE: not on the flood risk listAL5 4PF: not on the flood risk listAL5 4PG: not on the flood risk listAL5 4PH: not on the flood risk listAL5 4PJ: not on the flood risk listAL5 4PL: not on the flood risk listAL5 4PN: not on the flood risk listAL5 4PP: not on the flood risk listAL5 4PQ: not on the flood risk listAL5 4PR: not on the flood risk listAL5 4PT: not on the flood risk listAL5 4PW: not on the flood risk listAL5 4QA: not on the flood risk listAL5 4QB: not on the flood risk listAL5 4QD: not on the flood risk listAL5 4QE: not on the flood risk listAL5 4QF: not on the flood risk listAL5 4QG: not on the flood risk listAL5 4QH: not on the flood risk listAL5 4QJ: not on the flood risk listAL5 4QL: not on the flood risk listAL5 4QN: not on the flood risk listAL5 4QP: not on the flood risk listAL5 4QQ: not on the flood risk listAL5 4QR: not on the flood risk listAL5 4QS: not on the flood risk listAL5 4QT: not on the flood risk listAL5 4QU: not on the flood risk listAL5 4QW: not on the flood risk listAL5 4QX: not on the flood risk listAL5 4QY: not on the flood risk listAL5 4QZ: not on the flood risk listAL5 4RA: not on the flood risk listAL5 4RD: not on the flood risk listAL5 4RE: not on the flood risk listAL5 4RF: not on the flood risk listAL5 4RG: not on the flood risk listAL5 4RH: not on the flood risk listAL5 4RL: not on the flood risk listAL5 4RN: not on the flood risk listAL5 4RP: not on the flood risk listAL5 4RQ: not on the flood risk listAL5 4RR: not on the flood risk listAL5 4RU: not on the flood risk listAL5 4RW: not on the flood risk listAL5 4SA: not on the flood risk listAL5 4SD: not on the flood risk listAL5 4SE: not on the flood risk listAL5 4SJ: not on the flood risk listAL5 4SL: not on the flood risk listAL5 4SP: not on the flood risk listAL5 4SQ: not on the flood risk listAL5 4SS: not on the flood risk listAL5 4ST: not on the flood risk listAL5 4SU: not on the flood risk listAL5 4SW: not on the flood risk listAL5 4SX: not on the flood risk listAL5 4SY: not on the flood risk listAL5 4TA: not on the flood risk listAL5 4TB: not on the flood risk listAL5 4TD: not on the flood risk listAL5 4TE: not on the flood risk listAL5 4TF: not on the flood risk listAL5 4TG: not on the flood risk listAL5 4TH: not on the flood risk listAL5 4TJ: not on the flood risk listAL5 4TL: not on the flood risk listAL5 4TN: not on the flood risk listAL5 4TP: not on the flood risk listAL5 4TQ: not on the flood risk listAL5 4TR: not on the flood risk listAL5 4TS: not on the flood risk listAL5 4TT: not on the flood risk listAL5 4TU: not on the flood risk listAL5 4TW: not on the flood risk listAL5 4TX: not on the flood risk listAL5 4TY: not on the flood risk listAL5 4TZ: not on the flood risk listAL5 4UB: not on the flood risk listAL5 4UE: not on the flood risk listAL5 4UH: not on the flood risk listAL5 4UJ: not on the flood risk listAL5 4UL: not on the flood risk listAL5 4US: not on the flood risk listAL5 4UT: not on the flood risk listAL5 4UW: not on the flood risk listAL5 4UX: not on the flood risk listAL5 4UZ: not on the flood risk listAL5 4XA: not on the flood risk listAL5 4XB: not on the flood risk listAL5 4XD: not on the flood risk listAL5 4XE: not on the flood risk listAL5 4XF: not on the flood risk listAL5 4XG: not on the flood risk listAL5 4XH: not on the flood risk listAL5 4XS: not on the flood risk listAL5 4XT: not on the flood risk listAL5 4NQ: very low flood risk onlyAL5 4UU: very low flood risk onlyAL5 4NH: low flood risk at worstAL5 4UN: high flood risk Harpenden Map of every postcode in the AL5 4 sector, by flood risk Of the 252 postcodes in the AL5 4 sector that ONS places, 1 have a home or business at high risk, 1 are at low risk at worst, 2 are at very low risk only and 248 are not on the Environment Agency's at-risk list. One postcode lies beyond the edge and is listed under the map. Places named: Harpenden. Drawn over roads, rivers and built-up areas. North is up; the scale bar is 500 m. Harpenden
  • A home or business at high risk: 1
  • At medium risk at worst: 0
  • At low risk at worst: 1
  • At very low risk only: 2
  • Not on the at-risk list: 248

Of the 252 postcodes in the AL5 4 sector that ONS places, 1 have a home or business at high risk, 1 are at low risk at worst, 2 are at very low risk only and 248 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.

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.

AL5 4UN11 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.

AL5 4ZJ

What do homes sell for in AL5 4?

Homes in AL5 4 sold for a typical £792,500 in the 12 months to August 2026, across 78 sales, up 22.8% on the 12 months before, HM Land Registry's figures show.

£792,500 typical price, the 12 months to August 2026
£645,250 12 months to August 2025
▲ up 22.8% on the 12 months before
  • Detached £1,377,500 20 sales
  • Semi-detached £865,000 26 sales
  • Terraced £625,000 12 sales
  • Flat or maisonette £335,000 20 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 AL5 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 AL5 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.

AL5 4AAAL5 4ABAL5 4ADAL5 4AEAL5 4AFAL5 4AGAL5 4AHAL5 4AJAL5 4ALAL5 4ANAL5 4APAL5 4AQAL5 4ARAL5 4ASAL5 4ATAL5 4AUAL5 4AWAL5 4AXAL5 4AYAL5 4BAAL5 4BBAL5 4BDAL5 4BEAL5 4BGAL5 4BHAL5 4BJAL5 4BPAL5 4BQAL5 4BSAL5 4BTAL5 4BUAL5 4BWAL5 4BXAL5 4BZAL5 4DBAL5 4DDAL5 4DEAL5 4DFAL5 4DGAL5 4DHAL5 4DJAL5 4DNAL5 4DQAL5 4DUAL5 4DZAL5 4EAAL5 4EBAL5 4EDAL5 4EEAL5 4EFAL5 4EGAL5 4ELAL5 4EPAL5 4EQAL5 4ESAL5 4ETAL5 4EUAL5 4EWAL5 4EXAL5 4EYAL5 4EZAL5 4FBAL5 4FEAL5 4FFAL5 4FGAL5 4FHAL5 4FJAL5 4FLAL5 4FNAL5 4FPAL5 4FQAL5 4FRAL5 4FSAL5 4FUAL5 4FWAL5 4FXAL5 4GAAL5 4GBAL5 4GJAL5 4GWAL5 4GXAL5 4GZAL5 4HAAL5 4HBAL5 4HDAL5 4HEAL5 4HFAL5 4HGAL5 4HHAL5 4HJAL5 4HLAL5 4HNAL5 4HPAL5 4HQAL5 4HRAL5 4HSAL5 4HTAL5 4HUAL5 4HWAL5 4HXAL5 4HYAL5 4JAAL5 4JBAL5 4JDAL5 4JEAL5 4JFAL5 4JNAL5 4JPAL5 4JRAL5 4JSAL5 4JTAL5 4JUAL5 4JWAL5 4JXAL5 4JYAL5 4JZAL5 4LAAL5 4LBAL5 4LDAL5 4LEAL5 4LFAL5 4LGAL5 4LHAL5 4LJAL5 4LLAL5 4LNAL5 4LPAL5 4LQAL5 4LRAL5 4LSAL5 4LTAL5 4LUAL5 4LWAL5 4LXAL5 4LYAL5 4LZAL5 4NAAL5 4NBAL5 4NDAL5 4NFAL5 4NGAL5 4NHAL5 4NLAL5 4NQAL5 4NSAL5 4NTAL5 4NXAL5 4NYAL5 4NZAL5 4PAAL5 4PBAL5 4PDAL5 4PEAL5 4PFAL5 4PGAL5 4PHAL5 4PJAL5 4PLAL5 4PNAL5 4PPAL5 4PQAL5 4PRAL5 4PTAL5 4PWAL5 4QAAL5 4QBAL5 4QDAL5 4QEAL5 4QFAL5 4QGAL5 4QHAL5 4QJAL5 4QLAL5 4QNAL5 4QPAL5 4QQAL5 4QRAL5 4QSAL5 4QTAL5 4QUAL5 4QWAL5 4QXAL5 4QYAL5 4QZAL5 4RAAL5 4RDAL5 4REAL5 4RFAL5 4RGAL5 4RHAL5 4RLAL5 4RNAL5 4RPAL5 4RQAL5 4RRAL5 4RUAL5 4RWAL5 4SAAL5 4SDAL5 4SEAL5 4SJAL5 4SLAL5 4SPAL5 4SQAL5 4SSAL5 4STAL5 4SUAL5 4SWAL5 4SXAL5 4SYAL5 4TAAL5 4TBAL5 4TDAL5 4TEAL5 4TFAL5 4TGAL5 4THAL5 4TJAL5 4TLAL5 4TNAL5 4TPAL5 4TQAL5 4TRAL5 4TSAL5 4TTAL5 4TUAL5 4TWAL5 4TXAL5 4TYAL5 4TZAL5 4UBAL5 4UEAL5 4UHAL5 4UJAL5 4ULAL5 4UNAL5 4USAL5 4UTAL5 4UUAL5 4UWAL5 4UXAL5 4UZAL5 4XAAL5 4XBAL5 4XDAL5 4XEAL5 4XFAL5 4XGAL5 4XHAL5 4XSAL5 4XTAL5 4ZJ

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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