State Highway 16 is a New Zealand state highway linking central Auckland with Wellsford, via Auckland's Northwestern Motorway, Helensville and Kaukapakapa. It provides an alternative to SH 1 for traffic travelling between Auckland and parts of Northland from Wellsford northwards.

The New Zealand state highway network is the major national highway network in New Zealand. Nearly 100 roads in the North and South Islands are state highways. All state highways are administered by the NZ Transport Agency.