North London
N1, N1C, N2, N3, N4, N5, N6, N7, N8, N9, N10, N11, N12, N13, N14, N15, N16, N17, N18, N19, N20, N21, N22, NW1, NW2, NW3, NW4, NW5, NW6, NW7, NW8, NW9, NW10, NW11
South London
SE1, SE2, SE3, SE4, SE5, SE6, SE7, SE8, SE9, SE10, SE11, SE12, SE13, SE14, SE15, SE16, SE17, SE18, SE19, SE20, SE21, SE22, SE23, SE24, SE25, SE26, SE27, SE28, SW1, SW2, SW3, SW4, SW5, SW6, SW7, SW8, SW9, SW10, SW11, SW12, SW13, SW14, SW15, SW16, SW 17, SW18, SW19, SW20.
East London
E1, E2, E3, E4, E5, E6, E7, E8, E9, E10, E11, E12, E13, E14, E15, E16, E17, E18, E1W
West London
W1, W2, W3, W4, W5, W6, W7, W8, W9, W10, W11, W12, W13, W14, UB1, UB2, UB3, UB4, UB5, UB6, TW1, TW2, TW3, TW4, TW5, TW7, TW8, TW9
Central London
WC1, WC2, EC1, EC2, EC3, EC4
Harrow
HA0, HA1, HA2, HA3, HA4, HA5, HA6, HA7, HA8, HA9
Enfield
EN1, EN2, EN3, EN4, EN5, EN6, EN7, EN8, EN9, EN10, EN11
Essex
IG1, IG2, IG3, IG4, IG5, IG6, IG7, IG8, IG9, IG10, IG11, RM1, RM2, RM3, RM4, RM5, RM6, RM7, RM8, RM9, RM10, RM11, RM12, RM13, RM14
Chelmsford
CM5, CM16, CM17, CM18, CM19, CM20, CM21, CM22, CM23, CM24
Watford
WD3, WD4, WD5, WD6, WD7, WD17, WD18, WD19, WD23, WD24, WD25.
St. Albans/Hatfield
AL1, AL2, AL3, AL4, AL5, AL6, AL7 AL8, AL9, 10.
Uxbridge
UB1, UB2, UB3, UB4, UB5, UB6, UB7, UB8, UB9, UB10, UB11.