SL4 1 postcode sector in the SL4 district

SL4 1 is a sector of the SL4 district: every postcode that starts SL4 1. It has 158 postcodes in use, 18 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 SL4 1 sector, by flood risk

Map of every postcode in the SL4 1 sector, by flood risk Of the 158 postcodes in the SL4 1 sector that ONS places, 4 have a home or business at high risk, 9 are at medium risk at worst, 37 are at low risk at worst, 4 are at very low risk only and 104 are not on the Environment Agency's at-risk list. One group of postcodes at high or medium risk is outlined: 6 postcodes at high or medium risk. Places named: Eton & Castle. Drawn over roads, rivers and built-up areas. North is up; the scale bar is 250 m. A308 SL4 1AA: not on the flood risk listSL4 1AF: not on the flood risk listSL4 1AG: not on the flood risk listSL4 1AT: not on the flood risk listSL4 1BA: not on the flood risk listSL4 1BB: not on the flood risk listSL4 1BE: not on the flood risk listSL4 1BG: not on the flood risk listSL4 1BH: not on the flood risk listSL4 1BN: not on the flood risk listSL4 1BP: not on the flood risk listSL4 1BQ: not on the flood risk listSL4 1BY: not on the flood risk listSL4 1BZ: not on the flood risk listSL4 1DA: not on the flood risk listSL4 1DD: not on the flood risk listSL4 1DG: not on the flood risk listSL4 1DH: not on the flood risk listSL4 1DL: not on the flood risk listSL4 1DN: not on the flood risk listSL4 1DS: not on the flood risk listSL4 1DT: not on the flood risk listSL4 1DU: not on the flood risk listSL4 1DW: not on the flood risk listSL4 1EA: not on the flood risk listSL4 1ED: not on the flood risk listSL4 1EF: not on the flood risk listSL4 1EG: not on the flood risk listSL4 1EH: not on the flood risk listSL4 1EL: not on the flood risk listSL4 1EN: not on the flood risk listSL4 1EP: not on the flood risk listSL4 1EQ: not on the flood risk listSL4 1ER: not on the flood risk listSL4 1ET: not on the flood risk listSL4 1EU: not on the flood risk listSL4 1EW: not on the flood risk listSL4 1FA: not on the flood risk listSL4 1GF: not on the flood risk listSL4 1HA: not on the flood risk listSL4 1HB: not on the flood risk listSL4 1HD: not on the flood risk listSL4 1HE: not on the flood risk listSL4 1HF: not on the flood risk listSL4 1HG: not on the flood risk listSL4 1HH: not on the flood risk listSL4 1HJ: not on the flood risk listSL4 1HL: not on the flood risk listSL4 1HN: not on the flood risk listSL4 1HP: not on the flood risk listSL4 1HQ: not on the flood risk listSL4 1HR: not on the flood risk listSL4 1HS: not on the flood risk listSL4 1HT: not on the flood risk listSL4 1HU: not on the flood risk listSL4 1HW: not on the flood risk listSL4 1HX: not on the flood risk listSL4 1HY: not on the flood risk listSL4 1HZ: not on the flood risk listSL4 1JA: not on the flood risk listSL4 1JB: not on the flood risk listSL4 1JD: not on the flood risk listSL4 1JG: not on the flood risk listSL4 1JH: not on the flood risk listSL4 1JJ: not on the flood risk listSL4 1JL: not on the flood risk listSL4 1JN: not on the flood risk listSL4 1JP: not on the flood risk listSL4 1JQ: not on the flood risk listSL4 1JU: not on the flood risk listSL4 1LA: not on the flood risk listSL4 1LB: not on the flood risk listSL4 1LD: not on the flood risk listSL4 1LH: not on the flood risk listSL4 1LJ: not on the flood risk listSL4 1LP: not on the flood risk listSL4 1LR: not on the flood risk listSL4 1LS: not on the flood risk listSL4 1LU: not on the flood risk listSL4 1LY: not on the flood risk listSL4 1NA: not on the flood risk listSL4 1NG: not on the flood risk listSL4 1NJ: not on the flood risk listSL4 1NQ: not on the flood risk listSL4 1PA: not on the flood risk listSL4 1PB: not on the flood risk listSL4 1PD: not on the flood risk listSL4 1PE: not on the flood risk listSL4 1PF: not on the flood risk listSL4 1PQ: not on the flood risk listSL4 1PR: not on the flood risk listSL4 1PW: not on the flood risk listSL4 1QD: not on the flood risk listSL4 1QG: not on the flood risk listSL4 1RL: not on the flood risk listSL4 1RQ: not on the flood risk listSL4 1SN: not on the flood risk listSL4 1TE: not on the flood risk listSL4 1UT: not on the flood risk listSL4 1YA: not on the flood risk listSL4 1DP: very low flood risk onlySL4 1PS: very low flood risk onlySL4 1QB: very low flood risk onlySL4 1TF: very low flood risk onlySL4 1BF: low flood risk at worstSL4 1JF: low flood risk at worstSL4 1PJ: low flood risk at worstSL4 1PL: low flood risk at worstSL4 1PU: low flood risk at worstSL4 1PX: low flood risk at worstSL4 1QL: low flood risk at worstSL4 1QP: low flood risk at worstSL4 1QW: low flood risk at worstSL4 1QZ: low flood risk at worstSL4 1RD: low flood risk at worstSL4 1RH: low flood risk at worstSL4 1RT: low flood risk at worstSL4 1RU: low flood risk at worstSL4 1RX: low flood risk at worstSL4 1RY: low flood risk at worstSL4 1RZ: low flood risk at worstSL4 1SA: low flood risk at worstSL4 1SB: low flood risk at worstSL4 1SH: low flood risk at worstSL4 1SJ: low flood risk at worstSL4 1SP: low flood risk at worstSL4 1SR: low flood risk at worstSL4 1SS: low flood risk at worstSL4 1ST: low flood risk at worstSL4 1SU: low flood risk at worstSL4 1SX: low flood risk at worstSL4 1SY: low flood risk at worstSL4 1SZ: low flood risk at worstSL4 1TA: low flood risk at worstSL4 1TB: low flood risk at worstSL4 1TD: low flood risk at worstSL4 1TH: low flood risk at worstSL4 1TQ: low flood risk at worstSL4 1TX: low flood risk at worstSL4 1AN: medium flood risk at worstSL4 1QT: medium flood risk at worstSL4 1QY: medium flood risk at worstSL4 1RB: medium flood risk at worstSL4 1RF: medium flood risk at worstSL4 1RS: medium flood risk at worstSL4 1SE: medium flood risk at worstSL4 1SQ: medium flood risk at worstSL4 1TG: medium flood risk at worstSL4 1QN: high flood riskSL4 1JE: high flood riskSL4 1QE: high flood riskSL4 1QX: high flood risk Eton & Castle 6 postcodes at high or medium risk, outlined: this goes to SL4 1QX, the one with most homes and businesses at high risk6 postcodes at high or medium risk Map of every postcode in the SL4 1 sector, by flood risk Of the 158 postcodes in the SL4 1 sector that ONS places, 4 have a home or business at high risk, 9 are at medium risk at worst, 37 are at low risk at worst, 4 are at very low risk only and 104 are not on the Environment Agency's at-risk list. One group of postcodes at high or medium risk is outlined: 6 postcodes at high or medium risk. Places named: Eton & Castle. Drawn over roads, rivers and built-up areas. North is up; the scale bar is 250 m. Eton & Castle
  • A home or business at high risk: 4
  • At medium risk at worst: 9
  • At low risk at worst: 37
  • At very low risk only: 4
  • Not on the at-risk list: 104
  • Outline: where 5 or more postcodes at high or medium risk lie together

Of the 158 postcodes in the SL4 1 sector that ONS places, 4 have a home or business at high risk, 9 are at medium risk at worst, 37 are at low risk at worst, 4 are at very low risk only and 104 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 150 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; 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.

SL4 1QX2 at high riskSL4 1JE1 at high riskSL4 1QE1 at high riskSL4 1QN1 at high risk

Where the postcodes at high or medium risk lie together

  • 6 postcodes at high or medium risk, outlined on the map. SL4 1QX, is the one with most homes and businesses at high risk.

What do homes sell for in SL4 1?

Homes in SL4 1 sold for a typical £468,000 in the 12 months to August 2026, across 35 sales, down 10.4% on the 12 months before, HM Land Registry's figures show.

£468,000 typical price, the 12 months to August 2026
£522,100 12 months to August 2025
▼ down 10.4% on the 12 months before
  • Detached 2 sales, too few to price
  • Semi-detached 4 sales, too few to price
  • Terraced £617,500 14 sales
  • Flat or maisonette £310,000 15 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 SL4 1. 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 SL4 1

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.

SL4 1AASL4 1AESL4 1AFSL4 1AGSL4 1ANSL4 1ATSL4 1BASL4 1BBSL4 1BESL4 1BFSL4 1BGSL4 1BHSL4 1BNSL4 1BPSL4 1BQSL4 1BYSL4 1BZSL4 1DASL4 1DDSL4 1DESL4 1DGSL4 1DHSL4 1DLSL4 1DNSL4 1DPSL4 1DSSL4 1DTSL4 1DUSL4 1DWSL4 1EASL4 1EDSL4 1EFSL4 1EGSL4 1EHSL4 1ELSL4 1ENSL4 1EPSL4 1EQSL4 1ERSL4 1ETSL4 1EUSL4 1EWSL4 1FASL4 1GFSL4 1GTSL4 1HASL4 1HBSL4 1HDSL4 1HESL4 1HFSL4 1HGSL4 1HHSL4 1HJSL4 1HLSL4 1HNSL4 1HPSL4 1HQSL4 1HRSL4 1HSSL4 1HTSL4 1HUSL4 1HWSL4 1HXSL4 1HYSL4 1HZSL4 1JASL4 1JBSL4 1JDSL4 1JESL4 1JFSL4 1JGSL4 1JHSL4 1JJSL4 1JLSL4 1JNSL4 1JPSL4 1JQSL4 1JUSL4 1LASL4 1LBSL4 1LDSL4 1LHSL4 1LJSL4 1LPSL4 1LRSL4 1LSSL4 1LUSL4 1LYSL4 1NASL4 1NGSL4 1NJSL4 1NQSL4 1PASL4 1PBSL4 1PDSL4 1PESL4 1PFSL4 1PJSL4 1PLSL4 1PQSL4 1PRSL4 1PSSL4 1PUSL4 1PWSL4 1PXSL4 1QBSL4 1QDSL4 1QESL4 1QFSL4 1QGSL4 1QLSL4 1QNSL4 1QPSL4 1QTSL4 1QWSL4 1QXSL4 1QYSL4 1QZSL4 1RBSL4 1RDSL4 1RFSL4 1RHSL4 1RLSL4 1RQSL4 1RSSL4 1RTSL4 1RUSL4 1RXSL4 1RYSL4 1RZSL4 1SASL4 1SBSL4 1SESL4 1SHSL4 1SJSL4 1SNSL4 1SPSL4 1SQSL4 1SRSL4 1SSSL4 1STSL4 1SUSL4 1SXSL4 1SYSL4 1SZSL4 1TASL4 1TBSL4 1TDSL4 1TESL4 1TFSL4 1TGSL4 1THSL4 1TQSL4 1TXSL4 1UTSL4 1WZSL4 1YASL4 1ZN

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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