As a box code, 4156 is used for 9 post office box locations.
PO Boxes using 4156
| Suburb | Town | Province |
|---|---|---|
| Broadlands | Mount Edgecombe | KwaZulu-Natal |
| Kindlewood | Mount Edgecombe | KwaZulu-Natal |
| Clayfield | Phoenix | KwaZulu-Natal |
| Clayfield Phase 1 | Phoenix | KwaZulu-Natal |
| Clayfield Phase 4 | Phoenix | KwaZulu-Natal |
| New Cottages | Phoenix | KwaZulu-Natal |
| Phoenix Industrial Area | Phoenix | KwaZulu-Natal |
| Phoenix Industrial Park | Phoenix | KwaZulu-Natal |
| Saccarine | Phoenix | KwaZulu-Natal |