WD18 postcode district: Watford and around, Hertfordshire

WD18 is a postcode district in Hertfordshire, with 714 postcodes in use in 6 sectors. It has postcodes in Watford and Rickmansworth. It is split between 2 councils: Watford (655 postcodes) and Three Rivers (59).

Postcodes in use
714
Sectors
6
Councils
2 councils
Places
2 places

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

Every postcode in WD18, by flood risk

Map of every postcode in WD18, by flood risk Of the 714 postcodes in WD18 that ONS places, 11 have a home or business at high risk, 2 are at medium risk at worst, 4 are at low risk at worst and 697 are not on the Environment Agency's at-risk list. One group of postcodes at high or medium risk is outlined: 7 postcodes at high or medium risk. Places named: Watford. Drawn over roads, rivers and built-up areas. North is up; the scale bar is 500 m. WD18 0AA: not on the flood risk listWD18 0AD: not on the flood risk listWD18 0AE: not on the flood risk listWD18 0AF: not on the flood risk listWD18 0AG: not on the flood risk listWD18 0AH: not on the flood risk listWD18 0AJ: not on the flood risk listWD18 0AL: not on the flood risk listWD18 0AQ: not on the flood risk listWD18 0AT: not on the flood risk listWD18 0AU: not on the flood risk listWD18 0AX: not on the flood risk listWD18 0AY: not on the flood risk listWD18 0AZ: not on the flood risk listWD18 0BA: not on the flood risk listWD18 0BB: not on the flood risk listWD18 0BD: not on the flood risk listWD18 0BE: not on the flood risk listWD18 0BF: not on the flood risk listWD18 0BG: not on the flood risk listWD18 0BH: not on the flood risk listWD18 0BJ: not on the flood risk listWD18 0BN: not on the flood risk listWD18 0BQ: not on the flood risk listWD18 0BS: not on the flood risk listWD18 0BT: not on the flood risk listWD18 0BU: not on the flood risk listWD18 0BW: not on the flood risk listWD18 0BX: not on the flood risk listWD18 0DB: not on the flood risk listWD18 0DD: not on the flood risk listWD18 0DE: not on the flood risk listWD18 0DF: not on the flood risk listWD18 0DH: not on the flood risk listWD18 0DJ: not on the flood risk listWD18 0DL: not on the flood risk listWD18 0DN: not on the flood risk listWD18 0DQ: not on the flood risk listWD18 0DT: not on the flood risk listWD18 0DU: not on the flood risk listWD18 0DW: not on the flood risk listWD18 0DX: not on the flood risk listWD18 0DY: not on the flood risk listWD18 0DZ: not on the flood risk listWD18 0EA: not on the flood risk listWD18 0EB: not on the flood risk listWD18 0EE: not on the flood risk listWD18 0EF: not on the flood risk listWD18 0EG: not on the flood risk listWD18 0EH: not on the flood risk listWD18 0EJ: not on the flood risk listWD18 0EN: not on the flood risk listWD18 0EQ: not on the flood risk listWD18 0ER: not on the flood risk listWD18 0ES: not on the flood risk listWD18 0ET: not on the flood risk listWD18 0EU: not on the flood risk listWD18 0EX: not on the flood risk listWD18 0EY: not on the flood risk listWD18 0EZ: not on the flood risk listWD18 0FB: not on the flood risk listWD18 0FJ: not on the flood risk listWD18 0GA: not on the flood risk listWD18 0GB: not on the flood risk listWD18 0GE: not on the flood risk listWD18 0GF: not on the flood risk listWD18 0GJ: not on the flood risk listWD18 0GN: not on the flood risk listWD18 0GP: not on the flood risk listWD18 0GQ: not on the flood risk listWD18 0GR: not on the flood risk listWD18 0GX: not on the flood risk listWD18 0GY: not on the flood risk listWD18 0HA: not on the flood risk listWD18 0HB: not on the flood risk listWD18 0HD: not on the flood risk listWD18 0HE: not on the flood risk listWD18 0HF: not on the flood risk listWD18 0HG: not on the flood risk listWD18 0HH: not on the flood risk listWD18 0HJ: not on the flood risk listWD18 0HL: not on the flood risk listWD18 0HN: not on the flood risk listWD18 0HQ: not on the flood risk listWD18 0HR: not on the flood risk listWD18 0HS: not on the flood risk listWD18 0HT: not on the flood risk listWD18 0HU: not on the flood risk listWD18 0HW: not on the flood risk listWD18 0HY: not on the flood risk listWD18 0JA: not on the flood risk listWD18 0JB: not on the flood risk listWD18 0JD: not on the flood risk listWD18 0JF: not on the flood risk listWD18 0JL: not on the flood risk listWD18 0JP: not on the flood risk listWD18 0JQ: not on the flood risk listWD18 0JR: not on the flood risk listWD18 0JS: not on the flood risk listWD18 0JU: not on the flood risk listWD18 0JW: not on the flood risk listWD18 0JX: not on the flood risk listWD18 0JY: not on the flood risk listWD18 0JZ: not on the flood risk listWD18 0LA: not on the flood risk listWD18 0LD: not on the flood risk listWD18 0LG: not on the flood risk listWD18 0LH: not on the flood risk listWD18 0LJ: not on the flood risk listWD18 0LN: not on the flood risk listWD18 0LQ: not on the flood risk listWD18 0LS: not on the flood risk listWD18 0LT: not on the flood risk listWD18 0LW: not on the flood risk listWD18 0LX: not on the flood risk listWD18 0LY: not on the flood risk listWD18 0NB: not on the flood risk listWD18 0ND: not on the flood risk listWD18 0NG: not on the flood risk listWD18 0NQ: not on the flood risk listWD18 0PA: not on the flood risk listWD18 0PB: not on the flood risk listWD18 0PD: not on the flood risk listWD18 0PJ: not on the flood risk listWD18 0PL: not on the flood risk listWD18 0PN: not on the flood risk listWD18 0PP: not on the flood risk listWD18 0PR: not on the flood risk listWD18 0PT: not on the flood risk listWD18 0PX: not on the flood risk listWD18 0PY: not on the flood risk listWD18 0QA: not on the flood risk listWD18 0QB: not on the flood risk listWD18 0QD: not on the flood risk listWD18 0QE: not on the flood risk listWD18 0QF: not on the flood risk listWD18 0QL: not on the flood risk listWD18 0QN: not on the flood risk listWD18 0QP: not on the flood risk listWD18 0QQ: not on the flood risk listWD18 0QR: not on the flood risk listWD18 0QS: not on the flood risk listWD18 0QU: not on the flood risk listWD18 0QX: not on the flood risk listWD18 0QY: not on the flood risk listWD18 0RA: not on the flood risk listWD18 0RB: not on the flood risk listWD18 0RD: not on the flood risk listWD18 0RE: not on the flood risk listWD18 0RG: not on the flood risk listWD18 0RH: not on the flood risk listWD18 0RL: not on the flood risk listWD18 0RN: not on the flood risk listWD18 0RP: not on the flood risk listWD18 0RQ: not on the flood risk listWD18 0RW: not on the flood risk listWD18 0SH: not on the flood risk listWD18 0SQ: not on the flood risk listWD18 0TG: not on the flood risk listWD18 0UB: not on the flood risk listWD18 0WA: not on the flood risk listWD18 0WB: not on the flood risk listWD18 0WF: not on the flood risk listWD18 0WJ: not on the flood risk listWD18 0WN: not on the flood risk listWD18 0WQ: not on the flood risk listWD18 0WR: not on the flood risk listWD18 0WU: not on the flood risk listWD18 0WY: not on the flood risk listWD18 0XP: not on the flood risk listWD18 0XQ: not on the flood risk listWD18 0XZ: not on the flood risk listWD18 1SA: not on the flood risk listWD18 6AA: not on the flood risk listWD18 6AB: not on the flood risk listWD18 6AD: not on the flood risk listWD18 6AE: not on the flood risk listWD18 6AF: not on the flood risk listWD18 6AG: not on the flood risk listWD18 6AH: not on the flood risk listWD18 6BW: not on the flood risk listWD18 6FU: not on the flood risk listWD18 6GB: not on the flood risk listWD18 6GD: not on the flood risk listWD18 6GE: not on the flood risk listWD18 6GF: not on the flood risk listWD18 6GG: not on the flood risk listWD18 6GH: not on the flood risk listWD18 6GJ: not on the flood risk listWD18 6GL: not on the flood risk listWD18 6GN: not on the flood risk listWD18 6GQ: not on the flood risk listWD18 6GR: not on the flood risk listWD18 6GS: not on the flood risk listWD18 6GT: not on the flood risk listWD18 6GU: not on the flood risk listWD18 6GW: not on the flood risk listWD18 6GY: not on the flood risk listWD18 6JD: not on the flood risk listWD18 6JG: not on the flood risk listWD18 6JH: not on the flood risk listWD18 6JJ: not on the flood risk listWD18 6JL: not on the flood risk listWD18 6JN: not on the flood risk listWD18 6JP: not on the flood risk listWD18 6JQ: not on the flood risk listWD18 6JR: not on the flood risk listWD18 6JS: not on the flood risk listWD18 6JT: not on the flood risk listWD18 6JU: not on the flood risk listWD18 6JW: not on the flood risk listWD18 6JX: not on the flood risk listWD18 6JY: not on the flood risk listWD18 6JZ: not on the flood risk listWD18 6LA: not on the flood risk listWD18 6LB: not on the flood risk listWD18 6LD: not on the flood risk listWD18 6LE: not on the flood risk listWD18 6LF: not on the flood risk listWD18 6LG: not on the flood risk listWD18 6LJ: not on the flood risk listWD18 6LL: not on the flood risk listWD18 6NP: not on the flood risk listWD18 6NS: not on the flood risk listWD18 6NT: not on the flood risk listWD18 6NU: not on the flood risk listWD18 6NW: not on the flood risk listWD18 6NX: not on the flood risk listWD18 6NY: not on the flood risk listWD18 6NZ: not on the flood risk listWD18 6PA: not on the flood risk listWD18 6PB: not on the flood risk listWD18 6PD: not on the flood risk listWD18 6PE: not on the flood risk listWD18 6PF: not on the flood risk listWD18 6PG: not on the flood risk listWD18 6PH: not on the flood risk listWD18 6PJ: not on the flood risk listWD18 6PL: not on the flood risk listWD18 6PN: not on the flood risk listWD18 6PP: not on the flood risk listWD18 6PQ: not on the flood risk listWD18 6PR: not on the flood risk listWD18 6PS: not on the flood risk listWD18 6PT: not on the flood risk listWD18 6PU: not on the flood risk listWD18 6PW: not on the flood risk listWD18 6PX: not on the flood risk listWD18 6PY: not on the flood risk listWD18 6PZ: not on the flood risk listWD18 6QF: not on the flood risk listWD18 6QG: not on the flood risk listWD18 6QS: not on the flood risk listWD18 6SD: not on the flood risk listWD18 6SF: not on the flood risk listWD18 6ST: not on the flood risk listWD18 6SU: not on the flood risk listWD18 6TA: not on the flood risk listWD18 6TQ: not on the flood risk listWD18 6UP: not on the flood risk listWD18 6UQ: not on the flood risk listWD18 6UR: not on the flood risk listWD18 6US: not on the flood risk listWD18 6UT: not on the flood risk listWD18 6UW: not on the flood risk listWD18 6UZ: not on the flood risk listWD18 6XE: not on the flood risk listWD18 6XL: not on the flood risk listWD18 6XR: not on the flood risk listWD18 7AD: not on the flood risk listWD18 7AE: not on the flood risk listWD18 7AF: not on the flood risk listWD18 7AG: not on the flood risk listWD18 7AH: not on the flood risk listWD18 7AJ: not on the flood risk listWD18 7AL: not on the flood risk listWD18 7AN: not on the flood risk listWD18 7AP: not on the flood risk listWD18 7AQ: not on the flood risk listWD18 7AR: not on the flood risk listWD18 7AS: not on the flood risk listWD18 7AT: not on the flood risk listWD18 7AX: not on the flood risk listWD18 7AZ: not on the flood risk listWD18 7BD: not on the flood risk listWD18 7BE: not on the flood risk listWD18 7BG: not on the flood risk listWD18 7BH: not on the flood risk listWD18 7BJ: not on the flood risk listWD18 7BL: not on the flood risk listWD18 7BP: not on the flood risk listWD18 7BQ: not on the flood risk listWD18 7BS: not on the flood risk listWD18 7BU: not on the flood risk listWD18 7BW: not on the flood risk listWD18 7BX: not on the flood risk listWD18 7BY: not on the flood risk listWD18 7BZ: not on the flood risk listWD18 7DA: not on the flood risk listWD18 7DB: not on the flood risk listWD18 7DD: not on the flood risk listWD18 7DE: not on the flood risk listWD18 7DG: not on the flood risk listWD18 7DH: not on the flood risk listWD18 7DN: not on the flood risk listWD18 7DP: not on the flood risk listWD18 7DR: not on the flood risk listWD18 7DS: not on the flood risk listWD18 7DT: not on the flood risk listWD18 7DU: not on the flood risk listWD18 7DX: not on the flood risk listWD18 7DY: not on the flood risk listWD18 7DZ: not on the flood risk listWD18 7EA: not on the flood risk listWD18 7EB: not on the flood risk listWD18 7ED: not on the flood risk listWD18 7EE: not on the flood risk listWD18 7EF: not on the flood risk listWD18 7EG: not on the flood risk listWD18 7EH: not on the flood risk listWD18 7EJ: not on the flood risk listWD18 7EL: not on the flood risk listWD18 7EN: not on the flood risk listWD18 7EP: not on the flood risk listWD18 7EQ: not on the flood risk listWD18 7ER: not on the flood risk listWD18 7ES: not on the flood risk listWD18 7ET: not on the flood risk listWD18 7EU: not on the flood risk listWD18 7EW: not on the flood risk listWD18 7EX: not on the flood risk listWD18 7EY: not on the flood risk listWD18 7FA: not on the flood risk listWD18 7FH: not on the flood risk listWD18 7FR: not on the flood risk listWD18 7GA: not on the flood risk listWD18 7GE: not on the flood risk listWD18 7GF: not on the flood risk listWD18 7GR: not on the flood risk listWD18 7HA: not on the flood risk listWD18 7HB: not on the flood risk listWD18 7HF: not on the flood risk listWD18 7HG: not on the flood risk listWD18 7HJ: not on the flood risk listWD18 7HL: not on the flood risk listWD18 7HN: not on the flood risk listWD18 7HP: not on the flood risk listWD18 7HQ: not on the flood risk listWD18 7HR: not on the flood risk listWD18 7HS: not on the flood risk listWD18 7HT: not on the flood risk listWD18 7HU: not on the flood risk listWD18 7HW: not on the flood risk listWD18 7HX: not on the flood risk listWD18 7HY: not on the flood risk listWD18 7HZ: not on the flood risk listWD18 7JA: not on the flood risk listWD18 7JB: not on the flood risk listWD18 7JD: not on the flood risk listWD18 7JE: not on the flood risk listWD18 7JF: not on the flood risk listWD18 7JG: not on the flood risk listWD18 7JH: not on the flood risk listWD18 7JJ: not on the flood risk listWD18 7JL: not on the flood risk listWD18 7JN: not on the flood risk listWD18 7JP: not on the flood risk listWD18 7JQ: not on the flood risk listWD18 7JS: not on the flood risk listWD18 7JT: not on the flood risk listWD18 7JU: not on the flood risk listWD18 7JX: not on the flood risk listWD18 7LA: not on the flood risk listWD18 7LB: not on the flood risk listWD18 7LD: not on the flood risk listWD18 7LE: not on the flood risk listWD18 7LF: not on the flood risk listWD18 7LG: not on the flood risk listWD18 7LH: not on the flood risk listWD18 7LJ: not on the flood risk listWD18 7LL: not on the flood risk listWD18 7LN: not on the flood risk listWD18 7LP: not on the flood risk listWD18 7LQ: not on the flood risk listWD18 7LR: not on the flood risk listWD18 7LT: not on the flood risk listWD18 7LU: not on the flood risk listWD18 7LW: not on the flood risk listWD18 7LY: not on the flood risk listWD18 7NA: not on the flood risk listWD18 7NB: not on the flood risk listWD18 7ND: not on the flood risk listWD18 7NE: not on the flood risk listWD18 7NH: not on the flood risk listWD18 7NJ: not on the flood risk listWD18 7NL: not on the flood risk listWD18 7NN: not on the flood risk listWD18 7NP: not on the flood risk listWD18 7NQ: not on the flood risk listWD18 7NR: not on the flood risk listWD18 7NS: not on the flood risk listWD18 7NT: not on the flood risk listWD18 7NU: not on the flood risk listWD18 7NY: not on the flood risk listWD18 7NZ: not on the flood risk listWD18 7PA: not on the flood risk listWD18 7PD: not on the flood risk listWD18 7PE: not on the flood risk listWD18 7PG: not on the flood risk listWD18 7PH: not on the flood risk listWD18 7PL: not on the flood risk listWD18 7PN: not on the flood risk listWD18 7PS: not on the flood risk listWD18 7PT: not on the flood risk listWD18 7PX: not on the flood risk listWD18 7PY: not on the flood risk listWD18 7QB: not on the flood risk listWD18 7QD: not on the flood risk listWD18 7QE: not on the flood risk listWD18 7QF: not on the flood risk listWD18 7QG: not on the flood risk listWD18 7QH: not on the flood risk listWD18 7QJ: not on the flood risk listWD18 7QL: not on the flood risk listWD18 7QN: not on the flood risk listWD18 7QP: not on the flood risk listWD18 7QQ: not on the flood risk listWD18 7QR: not on the flood risk listWD18 7QS: not on the flood risk listWD18 7QX: not on the flood risk listWD18 7RA: not on the flood risk listWD18 7RB: not on the flood risk listWD18 7RD: not on the flood risk listWD18 7RE: not on the flood risk listWD18 7RH: not on the flood risk listWD18 7RL: not on the flood risk listWD18 7RN: not on the flood risk listWD18 7RP: not on the flood risk listWD18 7RQ: not on the flood risk listWD18 7RR: not on the flood risk listWD18 7RS: not on the flood risk listWD18 7RT: not on the flood risk listWD18 7RU: not on the flood risk listWD18 7RW: not on the flood risk listWD18 7RX: not on the flood risk listWD18 7RY: not on the flood risk listWD18 7RZ: not on the flood risk listWD18 7SA: not on the flood risk listWD18 7SB: not on the flood risk listWD18 7SH: not on the flood risk listWD18 7SJ: not on the flood risk listWD18 7SN: not on the flood risk listWD18 7SQ: not on the flood risk listWD18 7SR: not on the flood risk listWD18 7SS: not on the flood risk listWD18 7ST: not on the flood risk listWD18 7SX: not on the flood risk listWD18 7SY: not on the flood risk listWD18 7SZ: not on the flood risk listWD18 7TA: not on the flood risk listWD18 7TD: not on the flood risk listWD18 7UA: not on the flood risk listWD18 7UD: not on the flood risk listWD18 7UE: not on the flood risk listWD18 7UF: not on the flood risk listWD18 7UH: not on the flood risk listWD18 7UJ: not on the flood risk listWD18 7UL: not on the flood risk listWD18 7UN: not on the flood risk listWD18 7WR: not on the flood risk listWD18 8AD: not on the flood risk listWD18 8AG: not on the flood risk listWD18 8AJ: not on the flood risk listWD18 8AL: not on the flood risk listWD18 8AN: not on the flood risk listWD18 8AP: not on the flood risk listWD18 8AQ: not on the flood risk listWD18 8AR: not on the flood risk listWD18 8AS: not on the flood risk listWD18 8AT: not on the flood risk listWD18 8AU: not on the flood risk listWD18 8AX: not on the flood risk listWD18 8AY: not on the flood risk listWD18 8AZ: not on the flood risk listWD18 8BD: not on the flood risk listWD18 8BE: not on the flood risk listWD18 8BF: not on the flood risk listWD18 8GA: not on the flood risk listWD18 8JA: not on the flood risk listWD18 8JB: not on the flood risk listWD18 8JF: not on the flood risk listWD18 8JG: not on the flood risk listWD18 8JU: not on the flood risk listWD18 8PH: not on the flood risk listWD18 8PX: not on the flood risk listWD18 8QU: not on the flood risk listWD18 8QZ: not on the flood risk listWD18 8RH: not on the flood risk listWD18 8RL: not on the flood risk listWD18 8SA: not on the flood risk listWD18 8TF: not on the flood risk listWD18 8UA: not on the flood risk listWD18 8UJ: not on the flood risk listWD18 8UW: not on the flood risk listWD18 8WH: not on the flood risk listWD18 8WJ: not on the flood risk listWD18 8WL: not on the flood risk listWD18 8WN: not on the flood risk listWD18 8WP: not on the flood risk listWD18 8WQ: not on the flood risk listWD18 8WR: not on the flood risk listWD18 8WS: not on the flood risk listWD18 8WW: not on the flood risk listWD18 8XN: not on the flood risk listWD18 8XU: not on the flood risk listWD18 8YA: not on the flood risk listWD18 8YB: not on the flood risk listWD18 8YE: not on the flood risk listWD18 8YF: not on the flood risk listWD18 8YG: not on the flood risk listWD18 8YH: not on the flood risk listWD18 8YN: not on the flood risk listWD18 8YS: not on the flood risk listWD18 8YU: not on the flood risk listWD18 8YW: not on the flood risk listWD18 8YX: not on the flood risk listWD18 8YZ: not on the flood risk listWD18 9AA: not on the flood risk listWD18 9AB: not on the flood risk listWD18 9AD: not on the flood risk listWD18 9AE: not on the flood risk listWD18 9AF: not on the flood risk listWD18 9AG: not on the flood risk listWD18 9DA: not on the flood risk listWD18 9ER: not on the flood risk listWD18 9ET: not on the flood risk listWD18 9EU: not on the flood risk listWD18 9EZ: not on the flood risk listWD18 9HG: not on the flood risk listWD18 9JE: not on the flood risk listWD18 9NA: not on the flood risk listWD18 9PX: not on the flood risk listWD18 9QA: not on the flood risk listWD18 9QD: not on the flood risk listWD18 9QN: not on the flood risk listWD18 9QP: not on the flood risk listWD18 9QQ: not on the flood risk listWD18 9QR: not on the flood risk listWD18 9RE: not on the flood risk listWD18 9RF: not on the flood risk listWD18 9RS: not on the flood risk listWD18 9RU: not on the flood risk listWD18 9SB: not on the flood risk listWD18 9SP: not on the flood risk listWD18 9SR: not on the flood risk listWD18 9SS: not on the flood risk listWD18 9SW: not on the flood risk listWD18 9TB: not on the flood risk listWD18 9TD: not on the flood risk listWD18 9TL: not on the flood risk listWD18 9TS: not on the flood risk listWD18 9UD: not on the flood risk listWD18 9UN: not on the flood risk listWD18 9XG: not on the flood risk listWD18 9XT: not on the flood risk listWD18 0GS: low flood risk at worstWD18 0HZ: low flood risk at worstWD18 0LF: low flood risk at worstWD18 0LU: low flood risk at worstWD18 0DS: medium flood risk at worstWD18 6QE: medium flood risk at worstWD18 0DP: high flood riskWD18 0FE: high flood riskWD18 0FL: high flood riskWD18 0FN: high flood riskWD18 0FS: high flood riskWD18 0FT: high flood riskWD18 0LE: high flood riskWD18 6QT: high flood riskWD18 8SL: high flood riskWD18 8SN: high flood riskWD18 9QG: high flood risk Watford 7 postcodes at high or medium risk, outlined: this goes to WD18 0FN, the one with most homes and businesses at high risk7 postcodes at high or medium risk Map of every postcode in WD18, by flood risk Of the 714 postcodes in WD18 that ONS places, 11 have a home or business at high risk, 2 are at medium risk at worst, 4 are at low risk at worst and 697 are not on the Environment Agency's at-risk list. One group of postcodes at high or medium risk is outlined: 7 postcodes at high or medium risk. Places named: Watford. Drawn over roads, rivers and built-up areas. North is up; the scale bar is 1 km. A4125 Watford
  • A home or business at high risk: 11
  • At medium risk at worst: 2
  • At low risk at worst: 4
  • At very low risk only: 0
  • Not on the at-risk list: 697
  • Outline: where 5 or more postcodes at high or medium risk lie together

Of the 714 postcodes in WD18 that ONS places, 11 have a home or business at high risk, 2 are at medium risk at worst, 4 are at low risk at worst and 697 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.

The middle of its postcodes: latitude 51.6491, longitude -0.4146. 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

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

WD18 0FN18 at high riskWD18 0DP12 at high riskWD18 8SN12 at high riskWD18 0FL10 at high riskWD18 8SL9 at high riskWD18 6QT1 at high riskWD18 9QG1 at high riskWD18 0FE1 at high riskWD18 0FS1 at high riskWD18 0FT1 at high riskWD18 0LE1 at high risk

Where the postcodes at high or medium risk lie together

  • 7 postcodes at high or medium risk, outlined on the map. WD18 0FN, is the one with most homes and businesses at high risk.

What broadband can you get in WD18?

Ofcom reports on 595 of the 714 postcodes in WD18. At 528 of them every home and business can get gigabit broadband.

Postcodes where every home can get gigabit528 of 595
Postcodes where every home can get superfast580 of 595

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 WD18 at risk of flooding?

17 of the 714 postcodes in WD18 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 82 homes and businesses in an area at high or medium risk.

Homes and businesses in an area at risk, at 17 of 714 postcodes High: 67Medium: 15Low: 201

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 WD18?

Homes in WD18 sold for a typical £370,000 in the 12 months to August 2026, across 188 sales, down 7.5% on the 12 months before, HM Land Registry's figures show.

£370,000 typical price, the 12 months to August 2026
£400,000 12 months to August 2025
▼ down 7.5% on the 12 months before
  • Detached £901,000 5 sales
  • Semi-detached £522,500 18 sales
  • Terraced £415,000 65 sales
  • Flat or maisonette £283,750 100 sales

Each bar is that kind's typical price, against the most expensive kind here.

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 WD18

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

WD18 0203 postcodesWD18 192 postcodesWD18 6103 postcodesWD18 7211 postcodesWD18 863 postcodesWD18 942 postcodes
UK postcode format explained

Places in WD18

Towns and villages with postcodes in WD18, and how many each has here.

Watford postcodes,703Rickmansworth postcodes,9

Who covers WD18

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

  • Watford655
  • South West Hertfordshire59

Police force areas

  • Hertfordshire714

Next to WD18

WD17 postcode district WD19 postcode district All WD districts Watford postcodes

"Next to" is by number: the districts before and after WD18 in the WD area.

Check a postcode

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