CM1 postcode district: Chelmsford and around, Essex

CM1 is a postcode district in Essex, with 1,561 postcodes in use in 7 sectors. It has postcodes in Chelmsford, Writtle, Broomfield and 1 more place. It is split between 2 councils: Chelmsford (1,535 postcodes) and Uttlesford (26).

Postcodes in use
1,561
Sectors
7
Councils
2 councils
Places
4 places

Source: Office for National Statistics (ONS) Postcode Directory, August 2026, loaded 20 October 2026. See all our data sources

Every postcode in CM1, by flood risk

Map of every postcode in CM1, by flood risk Of the 1,561 postcodes in CM1 that ONS places, 23 have a home or business at high risk, 22 are at medium risk at worst, 36 are at low risk at worst, 5 are at very low risk only and 1,475 are not on the Environment Agency's at-risk list. One group of postcodes at high or medium risk is outlined: 8 postcodes at high or medium risk. Places named: Chelmsford, Galleywood, Writtle, Broomfield. Drawn over roads, rivers and built-up areas. North is up; the scale bar is 2.5 km. A130A131A1114 CM1 1AF: not on the flood risk listCM1 1AG: not on the flood risk listCM1 1AH: not on the flood risk listCM1 1AN: not on the flood risk listCM1 1AU: not on the flood risk listCM1 1AW: not on the flood risk listCM1 1BA: not on the flood risk listCM1 1BB: not on the flood risk listCM1 1DD: not on the flood risk listCM1 1DG: not on the flood risk listCM1 1DW: not on the flood risk listCM1 1EA: not on the flood risk listCM1 1EW: not on the flood risk listCM1 1FH: not on the flood risk listCM1 1FR: not on the flood risk listCM1 1FW: not on the flood risk listCM1 1GJ: not on the flood risk listCM1 1GN: not on the flood risk listCM1 1GR: not on the flood risk listCM1 1GU: not on the flood risk listCM1 1HF: not on the flood risk listCM1 1HH: not on the flood risk listCM1 1HU: not on the flood risk listCM1 1LR: not on the flood risk listCM1 1NL: not on the flood risk listCM1 1NY: not on the flood risk listCM1 1PE: not on the flood risk listCM1 1PH: not on the flood risk listCM1 1PY: not on the flood risk listCM1 1PZ: not on the flood risk listCM1 1QA: not on the flood risk listCM1 1QD: not on the flood risk listCM1 1QG: not on the flood risk listCM1 1QL: not on the flood risk listCM1 1QT: not on the flood risk listCM1 1RG: not on the flood risk listCM1 1RH: not on the flood risk listCM1 1RL: not on the flood risk listCM1 1RN: not on the flood risk listCM1 1RR: not on the flood risk listCM1 1RT: not on the flood risk listCM1 1RU: not on the flood risk listCM1 1RX: not on the flood risk listCM1 1RY: not on the flood risk listCM1 1SA: not on the flood risk listCM1 1SE: not on the flood risk listCM1 1SR: not on the flood risk listCM1 1TD: not on the flood risk listCM1 1TE: not on the flood risk listCM1 1TG: not on the flood risk listCM1 1WB: not on the flood risk listCM1 2AA: not on the flood risk listCM1 2AB: not on the flood risk listCM1 2AD: not on the flood risk listCM1 2AE: not on the flood risk listCM1 2AF: not on the flood risk listCM1 2AG: not on the flood risk listCM1 2AJ: not on the flood risk listCM1 2AL: not on the flood risk listCM1 2AN: not on the flood risk listCM1 2AP: not on the flood risk listCM1 2AQ: not on the flood risk listCM1 2AR: not on the flood risk listCM1 2AS: not on the flood risk listCM1 2AT: not on the flood risk listCM1 2BA: not on the flood risk listCM1 2BB: not on the flood risk listCM1 2BD: not on the flood risk listCM1 2BE: not on the flood risk listCM1 2BH: not on the flood risk listCM1 2BP: not on the flood risk listCM1 2BQ: not on the flood risk listCM1 2BS: not on the flood risk listCM1 2BT: not on the flood risk listCM1 2BW: not on the flood risk listCM1 2BZ: not on the flood risk listCM1 2DA: not on the flood risk listCM1 2DE: not on the flood risk listCM1 2DF: not on the flood risk listCM1 2DJ: not on the flood risk listCM1 2DL: not on the flood risk listCM1 2DN: not on the flood risk listCM1 2DP: not on the flood risk listCM1 2DT: not on the flood risk listCM1 2DW: not on the flood risk listCM1 2DZ: not on the flood risk listCM1 2EA: not on the flood risk listCM1 2EB: not on the flood risk listCM1 2EF: not on the flood risk listCM1 2EG: not on the flood risk listCM1 2EH: not on the flood risk listCM1 2EJ: not on the flood risk listCM1 2EL: not on the flood risk listCM1 2EU: not on the flood risk listCM1 2EW: not on the flood risk listCM1 2EX: not on the flood risk listCM1 2EY: not on the flood risk listCM1 2FN: not on the flood risk listCM1 2FU: not on the flood risk listCM1 2FZ: not on the flood risk listCM1 2GA: not on the flood risk listCM1 2GE: not on the flood risk listCM1 2GF: not on the flood risk listCM1 2GG: not on the flood risk listCM1 2GJ: not on the flood risk listCM1 2GL: not on the flood risk listCM1 2GN: not on the flood risk listCM1 2GQ: not on the flood risk listCM1 2HA: not on the flood risk listCM1 2HB: not on the flood risk listCM1 2HF: not on the flood risk listCM1 2HH: not on the flood risk listCM1 2HL: not on the flood risk listCM1 2HP: not on the flood risk listCM1 2HS: not on the flood risk listCM1 2JA: not on the flood risk listCM1 2JD: not on the flood risk listCM1 2JE: not on the flood risk listCM1 2JF: not on the flood risk listCM1 2JG: not on the flood risk listCM1 2JH: not on the flood risk listCM1 2JJ: not on the flood risk listCM1 2JL: not on the flood risk listCM1 2JP: not on the flood risk listCM1 2JX: not on the flood risk listCM1 2JY: not on the flood risk listCM1 2LA: not on the flood risk listCM1 2LB: not on the flood risk listCM1 2LD: not on the flood risk listCM1 2LF: not on the flood risk listCM1 2LH: not on the flood risk listCM1 2LJ: not on the flood risk listCM1 2LN: not on the flood risk listCM1 2LR: not on the flood risk listCM1 2LU: not on the flood risk listCM1 2LY: not on the flood risk listCM1 2NB: not on the flood risk listCM1 2ND: not on the flood risk listCM1 2NE: not on the flood risk listCM1 2NF: not on the flood risk listCM1 2NG: not on the flood risk listCM1 2NQ: not on the flood risk listCM1 2PA: not on the flood risk listCM1 2PB: not on the flood risk listCM1 2PD: not on the flood risk listCM1 2PE: not on the flood risk listCM1 2PJ: not on the flood risk listCM1 2PL: not on the flood risk listCM1 2PN: not on the flood risk listCM1 2PP: not on the flood risk listCM1 2PR: not on the flood risk listCM1 2PU: not on the flood risk listCM1 2PZ: not on the flood risk listCM1 2QE: not on the flood risk listCM1 2QH: not on the flood risk listCM1 2QL: not on the flood risk listCM1 2QU: not on the flood risk listCM1 2QZ: not on the flood risk listCM1 2RA: not on the flood risk listCM1 2RB: not on the flood risk listCM1 2RF: not on the flood risk listCM1 2RN: not on the flood risk listCM1 2RR: not on the flood risk listCM1 2RZ: not on the flood risk listCM1 2SA: not on the flood risk listCM1 2SB: not on the flood risk listCM1 2SD: not on the flood risk listCM1 2SE: not on the flood risk listCM1 2SL: not on the flood risk listCM1 2SP: not on the flood risk listCM1 2SR: not on the flood risk listCM1 2ST: not on the flood risk listCM1 2SU: not on the flood risk listCM1 2SX: not on the flood risk listCM1 2TE: not on the flood risk listCM1 2TF: not on the flood risk listCM1 2TH: not on the flood risk listCM1 2TJ: not on the flood risk listCM1 2TL: not on the flood risk listCM1 2TP: not on the flood risk listCM1 2TR: not on the flood risk listCM1 2TS: not on the flood risk listCM1 2TT: not on the flood risk listCM1 2TU: not on the flood risk listCM1 2TX: not on the flood risk listCM1 2TY: not on the flood risk listCM1 2UA: not on the flood risk listCM1 2UP: not on the flood risk listCM1 2UY: not on the flood risk listCM1 2WT: not on the flood risk listCM1 2XA: not on the flood risk listCM1 2XD: not on the flood risk listCM1 2XN: not on the flood risk listCM1 2XR: not on the flood risk listCM1 2XT: not on the flood risk listCM1 2XW: not on the flood risk listCM1 3AA: not on the flood risk listCM1 3AE: not on the flood risk listCM1 3AF: not on the flood risk listCM1 3AG: not on the flood risk listCM1 3AR: not on the flood risk listCM1 3AT: not on the flood risk listCM1 3AX: not on the flood risk listCM1 3BH: not on the flood risk listCM1 3BJ: not on the flood risk listCM1 3BL: not on the flood risk listCM1 3BP: not on the flood risk listCM1 3BS: not on the flood risk listCM1 3BT: not on the flood risk listCM1 3BX: not on the flood risk listCM1 3BZ: not on the flood risk listCM1 3DA: not on the flood risk listCM1 3DB: not on the flood risk listCM1 3DE: not on the flood risk listCM1 3DJ: not on the flood risk listCM1 3DL: not on the flood risk listCM1 3DP: not on the flood risk listCM1 3DR: not on the flood risk listCM1 3DT: not on the flood risk listCM1 3DU: not on the flood risk listCM1 3DX: not on the flood risk listCM1 3DY: not on the flood risk listCM1 3DZ: not on the flood risk listCM1 3EB: not on the flood risk listCM1 3ED: not on the flood risk listCM1 3EG: not on the flood risk listCM1 3EH: not on the flood risk listCM1 3EJ: not on the flood risk listCM1 3EL: not on the flood risk listCM1 3EQ: not on the flood risk listCM1 3EW: not on the flood risk listCM1 3EZ: not on the flood risk listCM1 3FE: not on the flood risk listCM1 3FF: not on the flood risk listCM1 3FH: not on the flood risk listCM1 3FJ: not on the flood risk listCM1 3FL: not on the flood risk listCM1 3FN: not on the flood risk listCM1 3GD: not on the flood risk listCM1 3GF: not on the flood risk listCM1 3GH: not on the flood risk listCM1 3GJ: not on the flood risk listCM1 3GL: not on the flood risk listCM1 3GR: not on the flood risk listCM1 3GS: not on the flood risk listCM1 3HD: not on the flood risk listCM1 3HE: not on the flood risk listCM1 3HF: not on the flood risk listCM1 3HG: not on the flood risk listCM1 3HH: not on the flood risk listCM1 3HJ: not on the flood risk listCM1 3HP: not on the flood risk listCM1 3HW: not on the flood risk listCM1 3HY: not on the flood risk listCM1 3JA: not on the flood risk listCM1 3JB: not on the flood risk listCM1 3JE: not on the flood risk listCM1 3JF: not on the flood risk listCM1 3JG: not on the flood risk listCM1 3JH: not on the flood risk listCM1 3JJ: not on the flood risk listCM1 3JL: not on the flood risk listCM1 3JQ: not on the flood risk listCM1 3JT: not on the flood risk listCM1 3JW: not on the flood risk listCM1 3JX: not on the flood risk listCM1 3JZ: not on the flood risk listCM1 3LF: not on the flood risk listCM1 3LG: not on the flood risk listCM1 3LJ: not on the flood risk listCM1 3LP: not on the flood risk listCM1 3LQ: not on the flood risk listCM1 3LT: not on the flood risk listCM1 3LY: not on the flood risk listCM1 3NB: not on the flood risk listCM1 3ND: not on the flood risk listCM1 3NE: not on the flood risk listCM1 3NF: not on the flood risk listCM1 3NJ: not on the flood risk listCM1 3NN: not on the flood risk listCM1 3NP: not on the flood risk listCM1 3NT: not on the flood risk listCM1 3NX: not on the flood risk listCM1 3NZ: not on the flood risk listCM1 3PA: not on the flood risk listCM1 3PB: not on the flood risk listCM1 3PE: not on the flood risk listCM1 3PF: not on the flood risk listCM1 3PH: not on the flood risk listCM1 3PJ: not on the flood risk listCM1 3PN: not on the flood risk listCM1 3PQ: not on the flood risk listCM1 3PR: not on the flood risk listCM1 3PS: not on the flood risk listCM1 3PU: not on the flood risk listCM1 3PX: not on the flood risk listCM1 3PZ: not on the flood risk listCM1 3QD: not on the flood risk listCM1 3QF: not on the flood risk listCM1 3QG: not on the flood risk listCM1 3QH: not on the flood risk listCM1 3QJ: not on the flood risk listCM1 3QL: not on the flood risk listCM1 3QP: not on the flood risk listCM1 3QR: not on the flood risk listCM1 3QS: not on the flood risk listCM1 3QT: not on the flood risk listCM1 3QU: not on the flood risk listCM1 3QW: not on the flood risk listCM1 3QY: not on the flood risk listCM1 3QZ: not on the flood risk listCM1 3RA: not on the flood risk listCM1 3RB: not on the flood risk listCM1 3RE: not on the flood risk listCM1 3RF: not on the flood risk listCM1 3RG: not on the flood risk listCM1 3RP: not on the flood risk listCM1 3RS: not on the flood risk listCM1 3RT: not on the flood risk listCM1 3RU: not on the flood risk listCM1 3RY: not on the flood risk listCM1 3SB: not on the flood risk listCM1 3SD: not on the flood risk listCM1 3SE: not on the flood risk listCM1 3SF: not on the flood risk listCM1 3SG: not on the flood risk listCM1 3SH: not on the flood risk listCM1 3SJ: not on the flood risk listCM1 3SL: not on the flood risk listCM1 3SN: not on the flood risk listCM1 3SP: not on the flood risk listCM1 3SQ: not on the flood risk listCM1 3SR: not on the flood risk listCM1 3SS: not on the flood risk listCM1 3ST: not on the flood risk listCM1 3TH: not on the flood risk listCM1 3UB: not on the flood risk listCM1 3US: not on the flood risk listCM1 3WR: not on the flood risk listCM1 3WS: not on the flood risk listCM1 3WT: not on the flood risk listCM1 4AA: not on the flood risk listCM1 4AB: not on the flood risk listCM1 4AD: not on the flood risk listCM1 4AJ: not on the flood risk listCM1 4AL: not on the flood risk listCM1 4AN: not on the flood risk listCM1 4AS: not on the flood risk listCM1 4AT: not on the flood risk listCM1 4AU: not on the flood risk listCM1 4AW: not on the flood risk listCM1 4AY: not on the flood risk listCM1 4BA: not on the flood risk listCM1 4BB: not on the flood risk listCM1 4BD: not on the flood risk listCM1 4BH: not on the flood risk listCM1 4BJ: not on the flood risk listCM1 4BS: not on the flood risk listCM1 4BT: not on the flood risk listCM1 4BW: not on the flood risk listCM1 4BX: not on the flood risk listCM1 4BY: not on the flood risk listCM1 4DA: not on the flood risk listCM1 4DB: not on the flood risk listCM1 4DD: not on the flood risk listCM1 4DE: not on the flood risk listCM1 4DF: not on the flood risk listCM1 4DG: not on the flood risk listCM1 4DP: not on the flood risk listCM1 4DQ: not on the flood risk listCM1 4DU: not on the flood risk listCM1 4DX: not on the flood risk listCM1 4DY: not on the flood risk listCM1 4DZ: not on the flood risk listCM1 4EB: not on the flood risk listCM1 4EE: not on the flood risk listCM1 4EF: not on the flood risk listCM1 4EG: not on the flood risk listCM1 4EP: not on the flood risk listCM1 4EX: not on the flood risk listCM1 4FD: not on the flood risk listCM1 4FF: not on the flood risk listCM1 4FJ: not on the flood risk listCM1 4FL: not on the flood risk listCM1 4FN: not on the flood risk listCM1 4FP: not on the flood risk listCM1 4FQ: not on the flood risk listCM1 4FR: not on the flood risk listCM1 4FT: not on the flood risk listCM1 4FW: not on the flood risk listCM1 4FX: not on the flood risk listCM1 4GD: not on the flood risk listCM1 4GF: not on the flood risk listCM1 4GH: not on the flood risk listCM1 4GJ: not on the flood risk listCM1 4GN: not on the flood risk listCM1 4GP: not on the flood risk listCM1 4GR: not on the flood risk listCM1 4GS: not on the flood risk listCM1 4HE: not on the flood risk listCM1 4HH: not on the flood risk listCM1 4HJ: not on the flood risk listCM1 4HL: not on the flood risk listCM1 4HN: not on the flood risk listCM1 4HT: not on the flood risk listCM1 4HW: not on the flood risk listCM1 4HX: not on the flood risk listCM1 4HZ: not on the flood risk listCM1 4JF: not on the flood risk listCM1 4JG: not on the flood risk listCM1 4JL: not on the flood risk listCM1 4JN: not on the flood risk listCM1 4JQ: not on the flood risk listCM1 4JT: not on the flood risk listCM1 4JU: not on the flood risk listCM1 4JX: not on the flood risk listCM1 4LB: not on the flood risk listCM1 4LD: not on the flood risk listCM1 4LE: not on the flood risk listCM1 4LF: not on the flood risk listCM1 4LG: not on the flood risk listCM1 4LJ: not on the flood risk listCM1 4LN: not on the flood risk listCM1 4LP: not on the flood risk listCM1 4LQ: not on the flood risk listCM1 4LR: not on the flood risk listCM1 4LS: not on the flood risk listCM1 4LU: not on the flood risk listCM1 4LW: not on the flood risk listCM1 4LX: not on the flood risk listCM1 4LY: not on the flood risk listCM1 4LZ: not on the flood risk listCM1 4NA: not on the flood risk listCM1 4NB: not on the flood risk listCM1 4NF: not on the flood risk listCM1 4NH: not on the flood risk listCM1 4NJ: not on the flood risk listCM1 4NL: not on the flood risk listCM1 4NN: not on the flood risk listCM1 4NP: not on the flood risk listCM1 4NQ: not on the flood risk listCM1 4NR: not on the flood risk listCM1 4NS: not on the flood risk listCM1 4NT: not on the flood risk listCM1 4NU: not on the flood risk listCM1 4NW: not on the flood risk listCM1 4NY: not on the flood risk listCM1 4PH: not on the flood risk listCM1 4PP: not on the flood risk listCM1 4PQ: not on the flood risk listCM1 4PR: not on the flood risk listCM1 4PS: not on the flood risk listCM1 4PT: not on the flood risk listCM1 4PU: not on the flood risk listCM1 4PX: not on the flood risk listCM1 4PY: not on the flood risk listCM1 4QA: not on the flood risk listCM1 4QB: not on the flood risk listCM1 4QD: not on the flood risk listCM1 4QH: not on the flood risk listCM1 4QJ: not on the flood risk listCM1 4QP: not on the flood risk listCM1 4QR: not on the flood risk listCM1 4QS: not on the flood risk listCM1 4QT: not on the flood risk listCM1 4QU: not on the flood risk listCM1 4QW: not on the flood risk listCM1 4QX: not on the flood risk listCM1 4QY: not on the flood risk listCM1 4QZ: not on the flood risk listCM1 4RA: not on the flood risk listCM1 4RB: not on the flood risk listCM1 4RD: not on the flood risk listCM1 4RE: not on the flood risk listCM1 4RG: not on the flood risk listCM1 4RL: not on the flood risk listCM1 4RN: not on the flood risk listCM1 4RQ: not on the flood risk listCM1 4RR: not on the flood risk listCM1 4RU: not on the flood risk listCM1 4RW: not on the flood risk listCM1 4RX: not on the flood risk listCM1 4SB: not on the flood risk listCM1 4SD: not on the flood risk listCM1 4SE: not on the flood risk listCM1 4SF: not on the flood risk listCM1 4SG: not on the flood risk listCM1 4SH: not on the flood risk listCM1 4SJ: not on the flood risk listCM1 4SQ: not on the flood risk listCM1 4SS: not on the flood risk listCM1 4ST: not on the flood risk listCM1 4SU: not on the flood risk listCM1 4SZ: not on the flood risk listCM1 4TA: not on the flood risk listCM1 4TB: not on the flood risk listCM1 4TD: not on the flood risk listCM1 4TE: not on the flood risk listCM1 4TF: not on the flood risk listCM1 4TG: not on the flood risk listCM1 4TJ: not on the flood risk listCM1 4TL: not on the flood risk listCM1 4TN: not on the flood risk listCM1 4TP: not on the flood risk listCM1 4TR: not on the flood risk listCM1 4TS: not on the flood risk listCM1 4TT: not on the flood risk listCM1 4TX: not on the flood risk listCM1 4TY: not on the flood risk listCM1 4UB: not on the flood risk listCM1 4UE: not on the flood risk listCM1 4UH: not on the flood risk listCM1 4UN: not on the flood risk listCM1 4UP: not on the flood risk listCM1 4UQ: not on the flood risk listCM1 4UR: not on the flood risk listCM1 4US: not on the flood risk listCM1 4UT: not on the flood risk listCM1 4UU: not on the flood risk listCM1 4UW: not on the flood risk listCM1 4UY: not on the flood risk listCM1 4WA: not on the flood risk listCM1 4WB: not on the flood risk listCM1 4WF: not on the flood risk listCM1 4WH: not on the flood risk listCM1 4WT: not on the flood risk listCM1 4XA: not on the flood risk listCM1 4XD: not on the flood risk listCM1 4XG: not on the flood risk listCM1 4XH: not on the flood risk listCM1 4XL: not on the flood risk listCM1 4XN: not on the flood risk listCM1 4XQ: not on the flood risk listCM1 4XR: not on the flood risk listCM1 4XW: not on the flood risk listCM1 4XX: not on the flood risk listCM1 4XY: not on the flood risk listCM1 4YA: not on the flood risk listCM1 4YD: not on the flood risk listCM1 4YE: not on the flood risk listCM1 4YG: not on the flood risk listCM1 4YJ: not on the flood risk listCM1 4YL: not on the flood risk listCM1 4YP: not on the flood risk listCM1 4YR: not on the flood risk listCM1 4ZB: not on the flood risk listCM1 6AF: not on the flood risk listCM1 6AG: not on the flood risk listCM1 6AJ: not on the flood risk listCM1 6AL: not on the flood risk listCM1 6AN: not on the flood risk listCM1 6AP: not on the flood risk listCM1 6AQ: not on the flood risk listCM1 6AR: not on the flood risk listCM1 6AS: not on the flood risk listCM1 6AT: not on the flood risk listCM1 6AU: not on the flood risk listCM1 6AX: not on the flood risk listCM1 6AY: not on the flood risk listCM1 6AZ: not on the flood risk listCM1 6BA: not on the flood risk listCM1 6BB: not on the flood risk listCM1 6BD: not on the flood risk listCM1 6BE: not on the flood risk listCM1 6BF: not on the flood risk listCM1 6BG: not on the flood risk listCM1 6BJ: not on the flood risk listCM1 6BL: not on the flood risk listCM1 6BN: not on the flood risk listCM1 6BP: not on the flood risk listCM1 6BQ: not on the flood risk listCM1 6BS: not on the flood risk listCM1 6BT: not on the flood risk listCM1 6BU: not on the flood risk listCM1 6BW: not on the flood risk listCM1 6BX: not on the flood risk listCM1 6BY: not on the flood risk listCM1 6BZ: not on the flood risk listCM1 6DA: not on the flood risk listCM1 6DB: not on the flood risk listCM1 6DE: not on the flood risk listCM1 6DG: not on the flood risk listCM1 6DL: not on the flood risk listCM1 6DN: not on the flood risk listCM1 6DP: not on the flood risk listCM1 6DR: not on the flood risk listCM1 6DS: not on the flood risk listCM1 6DT: not on the flood risk listCM1 6DU: not on the flood risk listCM1 6DW: not on the flood risk listCM1 6DY: not on the flood risk listCM1 6EA: not on the flood risk listCM1 6EB: not on the flood risk listCM1 6ED: not on the flood risk listCM1 6EE: not on the flood risk listCM1 6EG: not on the flood risk listCM1 6EH: not on the flood risk listCM1 6EJ: not on the flood risk listCM1 6EN: not on the flood risk listCM1 6ER: not on the flood risk listCM1 6EU: not on the flood risk listCM1 6EY: not on the flood risk listCM1 6EZ: not on the flood risk listCM1 6FA: not on the flood risk listCM1 6FB: not on the flood risk listCM1 6FD: not on the flood risk listCM1 6FE: not on the flood risk listCM1 6FH: not on the flood risk listCM1 6FJ: not on the flood risk listCM1 6FL: not on the flood risk listCM1 6FN: not on the flood risk listCM1 6FP: not on the flood risk listCM1 6FQ: not on the flood risk listCM1 6FR: not on the flood risk listCM1 6FS: not on the flood risk listCM1 6FT: not on the flood risk listCM1 6FW: not on the flood risk listCM1 6FX: not on the flood risk listCM1 6GA: not on the flood risk listCM1 6GB: not on the flood risk listCM1 6GD: not on the flood risk listCM1 6GE: not on the flood risk listCM1 6GG: not on the flood risk listCM1 6GJ: not on the flood risk listCM1 6GL: not on the flood risk listCM1 6GP: not on the flood risk listCM1 6GQ: not on the flood risk listCM1 6GR: not on the flood risk listCM1 6GT: not on the flood risk listCM1 6GU: not on the flood risk listCM1 6GY: not on the flood risk listCM1 6GZ: not on the flood risk listCM1 6HA: not on the flood risk listCM1 6HE: not on the flood risk listCM1 6HJ: not on the flood risk listCM1 6HL: not on the flood risk listCM1 6HN: not on the flood risk listCM1 6HR: not on the flood risk listCM1 6HS: not on the flood risk listCM1 6HT: not on the flood risk listCM1 6HU: not on the flood risk listCM1 6HX: not on the flood risk listCM1 6HY: not on the flood risk listCM1 6HZ: not on the flood risk listCM1 6JA: not on the flood risk listCM1 6JB: not on the flood risk listCM1 6JD: not on the flood risk listCM1 6JE: not on the flood risk listCM1 6JF: not on the flood risk listCM1 6JH: not on the flood risk listCM1 6JJ: not on the flood risk listCM1 6JN: not on the flood risk listCM1 6JP: not on the flood risk listCM1 6JQ: not on the flood risk listCM1 6JR: not on the flood risk listCM1 6JS: not on the flood risk listCM1 6JX: not on the flood risk listCM1 6JY: not on the flood risk listCM1 6JZ: not on the flood risk listCM1 6LD: not on the flood risk listCM1 6LF: not on the flood risk listCM1 6LG: not on the flood risk listCM1 6LH: not on the flood risk listCM1 6LJ: not on the flood risk listCM1 6LL: not on the flood risk listCM1 6LP: not on the flood risk listCM1 6LR: not on the flood risk listCM1 6LS: not on the flood risk listCM1 6LU: not on the flood risk listCM1 6LX: not on the flood risk listCM1 6LY: not on the flood risk listCM1 6LZ: not on the flood risk listCM1 6ND: not on the flood risk listCM1 6NF: not on the flood risk listCM1 6NH: not on the flood risk listCM1 6NL: not on the flood risk listCM1 6NN: not on the flood risk listCM1 6NP: not on the flood risk listCM1 6NR: not on the flood risk listCM1 6NS: not on the flood risk listCM1 6NT: not on the flood risk listCM1 6NW: not on the flood risk listCM1 6NY: not on the flood risk listCM1 6PE: not on the flood risk listCM1 6PJ: not on the flood risk listCM1 6PR: not on the flood risk listCM1 6PS: not on the flood risk listCM1 6QR: not on the flood risk listCM1 6QS: not on the flood risk listCM1 6QT: not on the flood risk listCM1 6QX: not on the flood risk listCM1 6QY: not on the flood risk listCM1 6QZ: not on the flood risk listCM1 6SS: not on the flood risk listCM1 6ST: not on the flood risk listCM1 6SX: not on the flood risk listCM1 6SZ: not on the flood risk listCM1 6TA: not on the flood risk listCM1 6TB: not on the flood risk listCM1 6TN: not on the flood risk listCM1 6TR: not on the flood risk listCM1 6TT: not on the flood risk listCM1 6TU: not on the flood risk listCM1 6TW: not on the flood risk listCM1 6TX: not on the flood risk listCM1 6TZ: not on the flood risk listCM1 6UA: not on the flood risk listCM1 6UB: not on the flood risk listCM1 6UD: not on the flood risk listCM1 6UG: not on the flood risk listCM1 6UH: not on the flood risk listCM1 6UL: not on the flood risk listCM1 6UN: not on the flood risk listCM1 6UP: not on the flood risk listCM1 6UQ: not on the flood risk listCM1 6UU: not on the flood risk listCM1 6UX: not on the flood risk listCM1 6XB: not on the flood risk listCM1 6XE: not on the flood risk listCM1 6XF: not on the flood risk listCM1 6XH: not on the flood risk listCM1 6XR: not on the flood risk listCM1 6XS: not on the flood risk listCM1 6XT: not on the flood risk listCM1 6XZ: not on the flood risk listCM1 6YE: not on the flood risk listCM1 6YR: not on the flood risk listCM1 6YT: not on the flood risk listCM1 6YU: not on the flood risk listCM1 6ZG: not on the flood risk listCM1 6ZP: not on the flood risk listCM1 6ZQ: not on the flood risk listCM1 7AA: not on the flood risk listCM1 7AB: not on the flood risk listCM1 7AD: not on the flood risk listCM1 7AG: not on the flood risk listCM1 7AH: not on the flood risk listCM1 7AJ: not on the flood risk listCM1 7AL: not on the flood risk listCM1 7AN: not on the flood risk listCM1 7AP: not on the flood risk listCM1 7AS: not on the flood risk listCM1 7AT: not on the flood risk listCM1 7AU: not on the flood risk listCM1 7AX: not on the flood risk listCM1 7AZ: not on the flood risk listCM1 7BB: not on the flood risk listCM1 7BE: not on the flood risk listCM1 7BG: not on the flood risk listCM1 7BH: not on the flood risk listCM1 7BL: not on the flood risk listCM1 7BN: not on the flood risk listCM1 7BP: not on the flood risk listCM1 7BT: not on the flood risk listCM1 7BU: not on the flood risk listCM1 7BW: not on the flood risk listCM1 7BX: not on the flood risk listCM1 7BY: not on the flood risk listCM1 7DB: not on the flood risk listCM1 7DJ: not on the flood risk listCM1 7DN: not on the flood risk listCM1 7DP: not on the flood risk listCM1 7DR: not on the flood risk listCM1 7DS: not on the flood risk listCM1 7DT: not on the flood risk listCM1 7DX: not on the flood risk listCM1 7DY: not on the flood risk listCM1 7DZ: not on the flood risk listCM1 7EA: not on the flood risk listCM1 7EB: not on the flood risk listCM1 7ED: not on the flood risk listCM1 7EH: not on the flood risk listCM1 7EJ: not on the flood risk listCM1 7EN: not on the flood risk listCM1 7EQ: not on the flood risk listCM1 7ER: not on the flood risk listCM1 7ET: not on the flood risk listCM1 7EU: not on the flood risk listCM1 7EW: not on the flood risk listCM1 7EX: not on the flood risk listCM1 7EY: not on the flood risk listCM1 7EZ: not on the flood risk listCM1 7FA: not on the flood risk listCM1 7FE: not on the flood risk listCM1 7FG: not on the flood risk listCM1 7FH: not on the flood risk listCM1 7FJ: not on the flood risk listCM1 7FL: not on the flood risk listCM1 7FP: not on the flood risk listCM1 7FQ: not on the flood risk listCM1 7FS: not on the flood risk listCM1 7FT: not on the flood risk listCM1 7FU: not on the flood risk listCM1 7FY: not on the flood risk listCM1 7GD: not on the flood risk listCM1 7GE: not on the flood risk listCM1 7GU: not on the flood risk listCM1 7HA: not on the flood risk listCM1 7HF: not on the flood risk listCM1 7HG: not on the flood risk listCM1 7HH: not on the flood risk listCM1 7HN: not on the flood risk listCM1 7HT: not on the flood risk listCM1 7HU: not on the flood risk listCM1 7HZ: not on the flood risk listCM1 7LE: not on the flood risk listCM1 7LF: not on the flood risk listCM1 7NS: not on the flood risk listCM1 7NY: not on the flood risk listCM1 7NZ: not on the flood risk listCM1 7PA: not on the flood risk listCM1 7PB: not on the flood risk listCM1 7PE: not on the flood risk listCM1 7PF: not on the flood risk listCM1 7PG: not on the flood risk listCM1 7PH: not on the flood risk listCM1 7PJ: not on the flood risk listCM1 7PL: not on the flood risk listCM1 7PT: not on the flood risk listCM1 7PU: not on the flood risk listCM1 7PZ: not on the flood risk listCM1 7QA: not on the flood risk listCM1 7QB: not on the flood risk listCM1 7QE: not on the flood risk listCM1 7QG: not on the flood risk listCM1 7QH: not on the flood risk listCM1 7QJ: not on the flood risk listCM1 7QP: not on the flood risk listCM1 7QW: not on the flood risk listCM1 7QY: not on the flood risk listCM1 7RB: not on the flood risk listCM1 7RE: not on the flood risk listCM1 7RF: not on the flood risk listCM1 7RL: not on the flood risk listCM1 7RP: not on the flood risk listCM1 7RR: not on the flood risk listCM1 7RS: not on the flood risk listCM1 7RT: not on the flood risk listCM1 7RU: not on the flood risk listCM1 7RW: not on the flood risk listCM1 7RY: not on the flood risk listCM1 7SA: not on the flood risk listCM1 7SB: not on the flood risk listCM1 7SD: not on the flood risk listCM1 7SE: not on the flood risk listCM1 7SF: not on the flood risk listCM1 7SJ: not on the flood risk listCM1 7SL: not on the flood risk listCM1 7SP: not on the flood risk listCM1 7SQ: not on the flood risk listCM1 7SS: not on the flood risk listCM1 7SW: not on the flood risk listCM1 7TA: not on the flood risk listCM1 7TE: not on the flood risk listCM1 7TG: not on the flood risk listCM1 7TP: not on the flood risk listCM1 7TQ: not on the flood risk listCM1 7TR: not on the flood risk listCM1 7WE: not on the flood risk listCM1 7ZA: not on the flood risk listCM1 7ZS: not on the flood risk listCM1 7ZT: not on the flood risk listCM1 9SX: not on the flood risk listCM1 2GR: very low flood risk onlyCM1 2NJ: very low flood risk onlyCM1 2NR: very low flood risk onlyCM1 2NT: very low flood risk onlyCM1 1BT: low flood risk at worstCM1 1EJ: low flood risk at worstCM1 1GL: low flood risk at worstCM1 1JF: low flood risk at worstCM1 1LG: low flood risk at worstCM1 1YQ: low flood risk at worstCM1 1RB: low flood risk at worstCM1 1SL: low flood risk at worstCM1 1WZ: low flood risk at worstCM1 1XF: low flood risk at worstCM1 1XG: low flood risk at worstCM1 2NS: low flood risk at worstCM1 2QT: low flood risk at worstCM1 2UD: low flood risk at worstCM1 2RS: low flood risk at worstCM1 2RX: low flood risk at worstCM1 2SJ: low flood risk at worstCM1 3EU: low flood risk at worstCM1 3SU: low flood risk at worstCM1 4EJ: low flood risk at worstCM1 4ED: low flood risk at worstCM1 4HB: low flood risk at worstCM1 4PF: low flood risk at worstCM1 4PE: low flood risk at worstCM1 4QL: low flood risk at worstCM1 4QN: low flood risk at worstCM1 4SA: low flood risk at worstCM1 4UA: low flood risk at worstCM1 1BD: medium flood risk at worstCM1 1GH: medium flood risk at worstCM1 1LE: medium flood risk at worstCM1 1FG: medium flood risk at worstCM1 1PB: medium flood risk at worstCM1 1PA: medium flood risk at worstCM1 1TW: medium flood risk at worstCM1 1TP: medium flood risk at worstCM1 2QR: medium flood risk at worstCM1 2QX: medium flood risk at worstCM1 2QY: medium flood risk at worstCM1 2RL: medium flood risk at worstCM1 3EA: medium flood risk at worstCM1 3RR: medium flood risk at worstCM1 4LT: medium flood risk at worstCM1 1AE: high flood riskCM1 1DH: high flood riskCM1 1GD: high flood riskCM1 1LQ: high flood riskCM1 1SQ: high flood riskCM1 2NX: high flood riskCM1 3ET: high flood riskCM1 3EX: high flood riskCM1 3RL: high flood riskCM1 3RN: high flood riskCM1 3RZ: high flood riskCM1 3SA: high flood riskCM1 4LH: high flood riskCM1 4LL: high flood riskCM1 4PB: high flood riskCM1 4PD: high flood riskCM1 4PZ: high flood riskCM1 4RY: high flood riskCM1 4RZ: high flood riskCM1 4SX: high flood riskCM1 4TZ: high flood riskCM1 7BQ: high flood risk ChelmsfordGalleywoodWrittleBroomfield 8 postcodes at high or medium risk, outlined: this goes to CM1 1AE, the one with most homes and businesses at high risk8 postcodes at high or medium risk Map of every postcode in CM1, by flood risk Of the 1,561 postcodes in CM1 that ONS places, 23 have a home or business at high risk, 22 are at medium risk at worst, 36 are at low risk at worst, 5 are at very low risk only and 1,475 are not on the Environment Agency's at-risk list. One group of postcodes at high or medium risk is outlined: 8 postcodes at high or medium risk. Places named: Chelmsford, Galleywood, Writtle, Broomfield. Drawn over roads, rivers and built-up areas. North is up; the scale bar is 2.5 km. A131 ChelmsfordGalleywoodWrittleBroomfield
  • A home or business at high risk: 23
  • At medium risk at worst: 22
  • At low risk at worst: 36
  • At very low risk only: 5
  • Not on the at-risk list: 1,475
  • Outline: where 5 or more postcodes at high or medium risk lie together

Of the 1,561 postcodes in CM1 that ONS places, 23 have a home or business at high risk, 22 are at medium risk at worst, 36 are at low risk at worst, 5 are at very low risk only and 1,475 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 160 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.

The middle of its postcodes: latitude 51.7475, longitude 0.4583. Open this area on OpenStreetMap

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

23 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.

CM1 3SA13 at high riskCM1 1DN8 at high riskCM1 1GD5 at high riskCM1 1LQ4 at high riskCM1 3RZ4 at high riskCM1 7BQ4 at high riskCM1 1AE3 at high riskCM1 3EX3 at high riskCM1 3RL3 at high riskCM1 3RN3 at high riskCM1 4RY2 at high riskCM1 1DH1 at high risk

Where the postcodes at high or medium risk lie together

  • 8 postcodes at high or medium risk, outlined on the map. CM1 1AE, is the one with most homes and businesses at high risk.

What broadband can you get in CM1?

Ofcom reports on 1,449 of the 1,561 postcodes in CM1. At 1,195 of them every home and business can get gigabit broadband, and at 4 some cannot get decent broadband (10 Mbit/s).

Postcodes where every home can get gigabit1,195 of 1,449
Postcodes where every home can get superfast1,373 of 1,449
Postcodes where some cannot get decent broadband4 of 1,449

Ofcom gives each postcode's share of homes and businesses, not how many there are, so these count postcodes. Each postcode page has its own figures. A provider's checker answers for one address.

Check one address on Ofcom's checker

Source: Ofcom, Connected Nations, Spring 2026, data for January 2026, Open Government Licence v3.0. How we use it

Is CM1 at risk of flooding?

86 of the 1,561 postcodes in CM1 have a home or business in an area at risk of flooding from rivers or the sea, the Environment Agency says. At those, it puts 314 homes and businesses in an area at high or medium risk.

Homes and businesses in an area at risk, at 86 of 1,561 postcodes High: 64Medium: 250Low: 662Very low: 101

High: 3.3% or more a year (1 in 30). Medium: 1% to 3.3% a year. Low: 0.1% to 1% a year. Very low: under 0.1% a year (1 in 1,000). Each band is the chance of flooding in any one year.

Homes and businesses in an area at risk of flooding from rivers or the sea, as the Environment Agency counts them, added up over the postcodes. It is for the land, not each building, and leaves out surface water, groundwater and sewers. Each postcode page has its own figures and its flood warning areas.

Source: Environment Agency, Risk of Flooding from Rivers and Sea (postcodes in areas at risk), published 6 July 2026, Open Government Licence v3.0. How we use it

What do homes sell for in CM1?

Homes in CM1 sold for a typical £395,000 in the 12 months to August 2026, across 739 sales, down 2.5% on the 12 months before, HM Land Registry's figures show.

£395,000 typical price, the 12 months to August 2026
12 months to August 2025
£405,000
12 months to August 2026
£395,000

▼ down 2.5% on the 12 months before

Detached£605,000 168 sales
Semi-detached£432,500 237 sales
Terraced£367,500 158 sales
Flat or maisonette£220,500 176 sales

Standard sales of homes at market value. A typical price is the median, the middle sale. Sales take weeks to be registered, so the last month or two are incomplete. Each postcode page gives the figure for its own postcode sector.

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 CM1

Pick a sector, then a postcode. A sector is the district plus the next digit.

CM1 1208 postcodesCM1 2253 postcodesCM1 3225 postcodesCM1 4313 postcodesCM1 6274 postcodesCM1 7208 postcodesCM1 980 postcodes
UK postcode format explained

Places in CM1

Towns and villages with postcodes in CM1, and how many each has here.

Chelmsford postcodes,1,148Writtle postcodes,114Broomfield postcodes,82Galleywood postcodes,1

Who covers CM1

How many of the district's postcodes in use fall under each council, constituency and police force area.

Councils

What council am I in?

Constituencies

  • Chelmsford1,080
  • North West Essex480
  • Maldon1

Police force areas

  • Essex1,561

Next to CM1

CM0 postcode district CM2 postcode district All CM districts Chelmsford postcodes

"Next to" is by number: the districts before and after CM1 in the CM area.

Check a postcode

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