London and Home Counties (Hertfordshire, Bedfordshire, Buckinghamshire, Essex, Middlesex)

Barnet, Borehamwood, Brookmans Park, Bushey, Cricklewood, Cuffley, Edgware, Elstree, Enfield, Finchley, Harlow, Harpenden, Harrow, Hatfield, Hatfield, Hertford, Little Heath, London Colney, Muswell Hill, Palmers Green, Pinner, Potters Bar, Radlett, Rickmansworth, St Albans, Stanmore, Stevenage, Waltham Abbey, Waltham Cross, Ware, Watford, Welham Green, Welwyn, Welwyn Garden City, Winchmore Hill,

Postcodes: AL1,AL2, AL3, AL4, AL5, AL6, AL7, AL8, AL9, AL10, EN1, EN2, EN3, EN4, EN5, EN6, EN7, EN8, EN9, EN10, EN11, HA1, HA2, HA3, HA4, HA5, HA7, HA8, HA9, N1, N2, N3, N4, N5, N6, N7, N8, N9, N10, N11, N12, N13, N14, N18, N19, N20, N21, SG1, SG2, SG3, SG4, SG5, SG6, SG7, SG8, SG9, SG10, SG11, WD1,WD2, WD3, WD4, WD5, WD6, WD7, WD8, WD9, WD10.