CO12 3 postcode sector in the CO12 district

CO12 3 is a sector of the CO12 district: every postcode that starts CO12 3. It has 226 postcodes in use, 6 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 CO12 3 sector, and which are new since 2020

Map of every postcode in the CO12 3 sector, by new since 2020 Of the 226 postcodes in the CO12 3 sector that ONS places, 1 are new since 2020 and 225 were in use before 2020. Places named: Harwich. Drawn over roads, rivers and built-up areas. North is up; the scale bar is 500 m. A120 CO12 3AA: before 2020CO12 3AB: before 2020CO12 3AG: before 2020CO12 3AH: before 2020CO12 3AJ: before 2020CO12 3AL: before 2020CO12 3AP: before 2020CO12 3AR: before 2020CO12 3AS: before 2020CO12 3AT: before 2020CO12 3AU: before 2020CO12 3AW: before 2020CO12 3AX: before 2020CO12 3BA: before 2020CO12 3BB: before 2020CO12 3BD: before 2020CO12 3BG: before 2020CO12 3BH: before 2020CO12 3BJ: before 2020CO12 3BN: before 2020CO12 3BP: before 2020CO12 3BQ: before 2020CO12 3BS: before 2020CO12 3BW: before 2020CO12 3BZ: before 2020CO12 3DA: before 2020CO12 3DB: before 2020CO12 3DD: before 2020CO12 3DE: before 2020CO12 3DF: before 2020CO12 3DG: before 2020CO12 3DJ: before 2020CO12 3DL: before 2020CO12 3DP: before 2020CO12 3DQ: before 2020CO12 3DR: before 2020CO12 3DS: before 2020CO12 3DT: before 2020CO12 3DU: before 2020CO12 3DX: before 2020CO12 3DY: before 2020CO12 3EA: before 2020CO12 3ED: before 2020CO12 3EE: before 2020CO12 3EF: before 2020CO12 3EG: before 2020CO12 3EJ: before 2020CO12 3EL: before 2020CO12 3EN: before 2020CO12 3EQ: before 2020CO12 3ER: before 2020CO12 3ES: before 2020CO12 3ET: before 2020CO12 3EU: before 2020CO12 3EX: before 2020CO12 3EY: before 2020CO12 3EZ: before 2020CO12 3FD: before 2020CO12 3FF: before 2020CO12 3FG: before 2020CO12 3FH: before 2020CO12 3FJ: before 2020CO12 3FL: before 2020CO12 3FN: before 2020CO12 3FP: before 2020CO12 3FR: before 2020CO12 3FS: before 2020CO12 3GS: before 2020CO12 3GT: before 2020CO12 3HA: before 2020CO12 3HB: before 2020CO12 3HF: before 2020CO12 3HG: before 2020CO12 3HH: before 2020CO12 3HJ: before 2020CO12 3HL: before 2020CO12 3HN: before 2020CO12 3HP: before 2020CO12 3HQ: before 2020CO12 3HR: before 2020CO12 3HS: before 2020CO12 3HT: before 2020CO12 3HU: before 2020CO12 3HW: before 2020CO12 3HX: before 2020CO12 3HY: before 2020CO12 3HZ: before 2020CO12 3JA: before 2020CO12 3JB: before 2020CO12 3JD: before 2020CO12 3JE: before 2020CO12 3JG: before 2020CO12 3JJ: before 2020CO12 3JQ: before 2020CO12 3JR: before 2020CO12 3JT: before 2020CO12 3JW: before 2020CO12 3JX: before 2020CO12 3JY: before 2020CO12 3JZ: before 2020CO12 3LA: before 2020CO12 3LB: before 2020CO12 3LD: before 2020CO12 3LF: before 2020CO12 3LG: before 2020CO12 3LH: before 2020CO12 3LJ: before 2020CO12 3LL: before 2020CO12 3LP: before 2020CO12 3LR: before 2020CO12 3LS: before 2020CO12 3LT: before 2020CO12 3LU: before 2020CO12 3LX: before 2020CO12 3LY: before 2020CO12 3LZ: before 2020CO12 3ND: before 2020CO12 3NE: before 2020CO12 3NF: before 2020CO12 3NG: before 2020CO12 3NH: before 2020CO12 3NJ: before 2020CO12 3NL: before 2020CO12 3NN: before 2020CO12 3NP: before 2020CO12 3NQ: before 2020CO12 3NR: before 2020CO12 3NS: before 2020CO12 3NW: before 2020CO12 3NY: before 2020CO12 3PA: before 2020CO12 3PB: before 2020CO12 3PD: before 2020CO12 3PF: before 2020CO12 3PH: before 2020CO12 3PL: before 2020CO12 3PN: before 2020CO12 3PP: before 2020CO12 3PQ: before 2020CO12 3PR: before 2020CO12 3PS: before 2020CO12 3PT: before 2020CO12 3PU: before 2020CO12 3PW: before 2020CO12 3PY: before 2020CO12 3PZ: before 2020CO12 3QA: before 2020CO12 3QB: before 2020CO12 3QE: before 2020CO12 3QF: before 2020CO12 3QG: before 2020CO12 3QH: before 2020CO12 3QJ: before 2020CO12 3QL: before 2020CO12 3QN: before 2020CO12 3QP: before 2020CO12 3QQ: before 2020CO12 3QT: before 2020CO12 3QU: before 2020CO12 3QW: before 2020CO12 3RA: before 2020CO12 3RD: before 2020CO12 3RF: before 2020CO12 3RG: before 2020CO12 3RH: before 2020CO12 3RJ: before 2020CO12 3RL: before 2020CO12 3RN: before 2020CO12 3RP: before 2020CO12 3RR: before 2020CO12 3RS: before 2020CO12 3RW: before 2020CO12 3RX: before 2020CO12 3RY: before 2020CO12 3RZ: before 2020CO12 3SA: before 2020CO12 3SB: before 2020CO12 3SD: before 2020CO12 3SE: before 2020CO12 3SF: before 2020CO12 3SG: before 2020CO12 3SH: before 2020CO12 3SJ: before 2020CO12 3SL: before 2020CO12 3SN: before 2020CO12 3SP: before 2020CO12 3SQ: before 2020CO12 3SR: before 2020CO12 3SS: before 2020CO12 3ST: before 2020CO12 3SU: before 2020CO12 3SW: before 2020CO12 3SX: before 2020CO12 3SZ: before 2020CO12 3TA: before 2020CO12 3TB: before 2020CO12 3TD: before 2020CO12 3TE: before 2020CO12 3TG: before 2020CO12 3TH: before 2020CO12 3TJ: before 2020CO12 3TL: before 2020CO12 3TN: before 2020CO12 3TP: before 2020CO12 3TQ: before 2020CO12 3TR: before 2020CO12 3TS: before 2020CO12 3TT: before 2020CO12 3TW: before 2020CO12 3TX: before 2020CO12 3TZ: before 2020CO12 3UA: before 2020CO12 3UB: before 2020CO12 3UD: before 2020CO12 3UE: before 2020CO12 3UF: before 2020CO12 3UH: before 2020CO12 3UJ: before 2020CO12 3UL: before 2020CO12 3FQ: new since 2020 Harwich Map of every postcode in the CO12 3 sector, by new since 2020 Of the 226 postcodes in the CO12 3 sector that ONS places, 1 are new since 2020 and 225 were in use before 2020. Places named: Harwich. Drawn over roads, rivers and built-up areas. North is up; the scale bar is 500 m. A120 Harwich
  • New since 2020: 1
  • In use before 2020: 225

Of the 226 postcodes in the CO12 3 sector that ONS places, 1 are new since 2020 and 225 were in use before 2020.

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. New since 2020 means it came into use in January 2020 or later. 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; when each came into use: the same directory; 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 newest postcode

CO12 3FQApril 2021

What do homes sell for in CO12 3?

Homes in CO12 3 sold for a typical £226,250 in the 12 months to August 2026, across 92 sales, down 3.7% on the 12 months before, HM Land Registry's figures show.

£226,250 typical price, the 12 months to August 2026
£235,000 12 months to August 2025
▼ down 3.7% on the 12 months before
  • Detached £340,000 25 sales
  • Semi-detached £235,000 10 sales
  • Terraced £191,250 42 sales
  • Flat or maisonette £133,000 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 CO12 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 CO12 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.

CO12 3AACO12 3ABCO12 3AGCO12 3AHCO12 3AJCO12 3ALCO12 3APCO12 3ARCO12 3ASCO12 3ATCO12 3AUCO12 3AWCO12 3AXCO12 3BACO12 3BBCO12 3BDCO12 3BECO12 3BGCO12 3BHCO12 3BJCO12 3BNCO12 3BPCO12 3BQCO12 3BSCO12 3BWCO12 3BZCO12 3DACO12 3DBCO12 3DDCO12 3DECO12 3DFCO12 3DGCO12 3DJCO12 3DLCO12 3DPCO12 3DQCO12 3DRCO12 3DSCO12 3DTCO12 3DUCO12 3DXCO12 3DYCO12 3EACO12 3EBCO12 3EDCO12 3EECO12 3EFCO12 3EGCO12 3EJCO12 3ELCO12 3ENCO12 3EQCO12 3ERCO12 3ESCO12 3ETCO12 3EUCO12 3EXCO12 3EYCO12 3EZCO12 3FDCO12 3FFCO12 3FGCO12 3FHCO12 3FJCO12 3FLCO12 3FNCO12 3FPCO12 3FQCO12 3FRCO12 3FSCO12 3GSCO12 3GTCO12 3HACO12 3HBCO12 3HFCO12 3HGCO12 3HHCO12 3HJCO12 3HLCO12 3HNCO12 3HPCO12 3HQCO12 3HRCO12 3HSCO12 3HTCO12 3HUCO12 3HWCO12 3HXCO12 3HYCO12 3HZCO12 3JACO12 3JBCO12 3JDCO12 3JECO12 3JFCO12 3JGCO12 3JJCO12 3JQCO12 3JRCO12 3JTCO12 3JWCO12 3JXCO12 3JYCO12 3JZCO12 3LACO12 3LBCO12 3LDCO12 3LFCO12 3LGCO12 3LHCO12 3LJCO12 3LLCO12 3LPCO12 3LRCO12 3LSCO12 3LTCO12 3LUCO12 3LXCO12 3LYCO12 3LZCO12 3NDCO12 3NECO12 3NFCO12 3NGCO12 3NHCO12 3NJCO12 3NLCO12 3NNCO12 3NPCO12 3NQCO12 3NRCO12 3NSCO12 3NWCO12 3NYCO12 3PACO12 3PBCO12 3PDCO12 3PECO12 3PFCO12 3PHCO12 3PJCO12 3PLCO12 3PNCO12 3PPCO12 3PQCO12 3PRCO12 3PSCO12 3PTCO12 3PUCO12 3PWCO12 3PXCO12 3PYCO12 3PZCO12 3QACO12 3QBCO12 3QECO12 3QFCO12 3QGCO12 3QHCO12 3QJCO12 3QLCO12 3QNCO12 3QPCO12 3QQCO12 3QTCO12 3QUCO12 3QWCO12 3RACO12 3RDCO12 3RFCO12 3RGCO12 3RHCO12 3RJCO12 3RLCO12 3RNCO12 3RPCO12 3RRCO12 3RSCO12 3RWCO12 3RXCO12 3RYCO12 3RZCO12 3SACO12 3SBCO12 3SDCO12 3SECO12 3SFCO12 3SGCO12 3SHCO12 3SJCO12 3SLCO12 3SNCO12 3SPCO12 3SQCO12 3SRCO12 3SSCO12 3STCO12 3SUCO12 3SWCO12 3SXCO12 3SZCO12 3TACO12 3TBCO12 3TDCO12 3TECO12 3TGCO12 3THCO12 3TJCO12 3TLCO12 3TNCO12 3TPCO12 3TQCO12 3TRCO12 3TSCO12 3TTCO12 3TWCO12 3TXCO12 3TZCO12 3UACO12 3UBCO12 3UDCO12 3UECO12 3UFCO12 3UHCO12 3UJCO12 3UL

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.

Check a postcode

Something wrong on this page? Report an error and we will check it against the source.