| Country: | NZL |
| Type: | SH |
| Route: | 12 |
| Map: | NZ-SH12 map.png |
| Length Km: | 217 |
| Direction A: | North |
| Terminus A: | at Ōhaeawai |
| Junction: | near Kaikohe at Kaikohe at Dargaville |
| Direction B: | South |
| Terminus B: | at Brynderwyn |
| Destinations: | Dargaville, Kaikohe, Hokianga Harbour |
| Previous Type: | SH |
| Previous Route: | 11 |
| Next Type: | SH |
| Next Route: | 14 |
State Highway 12 (SH 12) is a New Zealand state highway in the far north of the North Island. It connects with at both its northern and southern end. It runs close to the west coast of the Northland Region of New Zealand.
SH 12 starts in Ōhaeawai, running initially southwest to Kaikohe, during which it shares a short section of road with . It then turns roughly westwards, reaching the Hokianga harbour at its Omanaia River arm. It continues west, reaching Opononi and Ōmāpere at the mouth of the harbour, before turning southeast to parallel the coast. The highway briefly follows the valley of the Waimamaku River before winding through the Waipoua Kauri Forest, then follows the valley of the Kaihu River to Dargaville. At Dargaville, the highway meets, and continues southeastwards along the edge of the Wairoa River to Ruawai before turning eastwards. It briefly skirts the edge of the Arapaoa River arm of the Kaipara Harbour before passing through Paparoa and Maungaturoto and ending at its junction with SH 1 at Brynderwyn, 15km (09miles) south of Waipu.[1]