As a box code, 6143 is used for 5 post office box locations.
PO Boxes using 6143
| Suburb | Town | Province |
|---|---|---|
| Grahamstown Ext 4 | Makhanda (Grahamstown) | Eastern Cape |
| Grahamstown Ext 5 | Makhanda (Grahamstown) | Eastern Cape |
| Grahamstown Ext 6 | Makhanda (Grahamstown) | Eastern Cape |
| Kwavukile | Makhanda (Grahamstown) | Eastern Cape |
| Siphiwo Mazwayi | Siphiwo Mazwayi | Eastern Cape |