U
| Town name | Postal code |
| Ubombo | 3970 |
| Uitenhage | 6021 |
| Uitenhage | 6229 |
| Uitenhage | 6230 |
| Uitenhage | 6231 |
| Uitenhage | 6232 |
| Uitenhage | 6234 |
| Uitenhage | 6238 |
| Uitenhage | 6242 |
| Ulundi | 3838 |
| Umbogintwini | 4126 |
| Umbumbulu | 4105 |
| Umbumbulu | 4106 |
| Umhlali | 4391 |
| Umhlali | 4420 |
| Umhlanga Rocks | 4021 |
| Umhlanga Rocks | 4319 |
| Umhlanga Rocks | 4321 |
| Umhlanga Rocks | 4350 |
| Umkomaas | 4170 |
| Umkomaas | 4171 |
| Umlazi | 4031 |
| Umlazi | 4066 |
| Umlazi | 4089 |
| Umlazi | 4144 |
| Umlazi | 4148 |
| Umtata | 4740 |
| Umtata | 5035 |
| Umtata | 5100 |
| Umtata | 5101 |
| Umtata | 5102 |
| Umtata | 5103 |
| Umtata | 5104 |
| Umtata | 5105 |
| Umtata | 5106 |
| Umtata | 5107 |
| Umtata | 5108 |
| Umtata | 5109 |
| Umtata | 5111 |
| Umtata | 5113 |
| Umtata | 5114 |
| Umtata | 5115 |
| Umtata | 5116 |
| Umtata | 5117 |
| Umtata | 5127 |
| Umtata | 5180 |
| Umtentweni | 4235 |
| Umzimkulu | 3239 |
| Umzimkulu | 3298 |
| Umzimkulu | 3304 |
| Umzimkulu | 3307 |
| Umzinto | 3263 |
| Umzinto | 3266 |
| Umzinto | 4200 |
| Umzinto | 4201 |
| Umzinto | 4202 |
| Umzinto | 4204 |
| Umzinto | 4207 |
| Umzumbe | 4225 |
| Umzumbe | 4227 |
| Uniondale | 6460 |
| Uniondale | 6462 |
| Uniondale | 6463 |
| Uniondale | 6466 |
| Uniondale | 6467 |
| Uniondale | 6480 |
| Uniondale | 6490 |
| Upington | 8801 |
| Upington | 8805 |
| Upington | 8806 |
| Upington | 8807 |
| Upington | 8808 |
| Upington | 8809 |
| Upington | 8810 |
| Upington | 8813 |
| Upington | 8815 |
| Upington | 8816 |
| Upington | 8818 |
| Upington | 8820 |
| Upington | 8824 |
| Utrecht | 2980 |
| Uvongo | 4270 |
