| PO Number | Town / Place name | Code |
|---|---|---|
| 800 | Tiverton | |
| 801 | Wimbledon | |
| Ton-y-refail | ||
| 802 | Bampton | |
| 803 | Dulverton | |
| 804 | Topsham | |
| 805 | Torquay | |
| 806 | Torrington | |
| 807 | Totness | |
| Totnes | ||
| 808 | Towcester | |
| 809 | Merton | |
| Eastgate | ||
| 810 | Tring | |
| 811 | Montford Bridge | |
| 812 | Risborough | |
| Princes Risborough | ||
| 813 | Trowbridge | |
| 814 | Truro | |
| 815 | Cambourne | |
| 816 | Sunbury Common | |
| 817 | St. Ives | |
| 818 | Tonbridge | |
| Tonbridge Station Office | ||
| 819 | Aspatria | |
| 820 | Tunbridge Wells | |
| High St. B.O. Tunbridge Wells | ||
| Calverley Tunbridge Wells | ||
| High St. Tunbridge Wells | ||
| 821 | Tuxford | |
| Ashford, Middx | ||
| 822 | Uckfield | |
| 823 | Hailsham | |
| 824 | Ulverstone | |
| 825 | Uppingham | |
| 826 | Usk | |
| 827 | Uttoxeter | |
| 828 | Abbot's Bromley | |
| Lanchester | ||
| 829 | Sudbury | |
| Crowborough | ||
| 830 | Uxbridge | |
| 831 | Wakefield | |
| 832 | Wallingford | |
| 833 | Benson | |
| Chingford | ||
| Cowshill | ||
| 834 | Walsall | |
| 835 | Waltham Cross | |
| 836 | Wangford | |
| 837 | Wrentham | |
| Reeth | ||
| 838 | Southwold | |
| 839 | Wansford | |
| 840 | Deane | |
| 841 | Weldon | |
| Hednesford | ||
| 842 | Ware | |
| 843 | Wareham | |
| 844 | Corfe Castle | |
| 845 | Swanage | |
| 846 | Warminister | |
| 847 | Warrington | |
| 848 | Warwick | |
| 849 | Watford | |
| 850 | Wednesbury | |
| 851 | Weedon | |
| 852 | Welshpool | |
| 853 | Machynlleth | |
| 854 | Montgomery | |
| 855 | Chirbury | |
| South Ferndale | ||
| Tylorstown | ||
| 856 | Churchstoke | |
| Pumpsaint | ||
| 857 | Welford | |
| Silloth | ||
| 858 | Wellingboro' | |
| 859 | Wellington, Salop | |
| 860 | Wellington, Som | |
| 861 | Onllwyn | |
| 862 | Milverton | |
| 863 | Wells, Norfolk | |
| 864 | Wells, Som | |
| 865 | Welwyn | |
| 866 | Crynant | |
| 867 | Wendover | |
| 868 | West Bromwich | |
| 869 | Port Dinorwic | |
| 870 | Westbury | |
| 871 | Weston-super-Mare | |
| 872 | Wetherby | |
| 873 | Weymouth | |
| 874 | Wheatley | |
| Godstone Station | ||
| South Godstone | ||
| 875 | Whitby | |
| 876 | Whitchurch, Salop | |
| 877 | Whitehaven | |
| 878 | Wigan | |
| 879 | Wigton | |
| 880 | Allonbury | |
| Didsbury | ||
| 881 | Swindon Station | |
| 882 | Wimbourne | |
| 883 | Wincanton | |
| 884 | Henstridge Ash | |
| Aberbeig | ||
| 885 | Milborne Port | |
| Abertillery | ||
| 886 | Crumlin | |
| 887 | Stalbridge | |
| Cwmtillery | ||
| 888 | Winchester | |
| 889 | Elland | |
| 890 | Windsor | |
| 891 | Godstone | |
| 892 | Eton | |
| Chatteris | ||
| 893 | Wingham | |
| 894 | Winslow | |
| 895 | Wirksworth | |
| 896 | Abbots Langley | |
| 897 | Wisbeach | |
| Wisbech | ||
| 898 | Brightlingsea | |
| 899 | Hunstanton St. Edmonds | |
| Hunstanton |