Prior to 1930, the recommended route by the Automobile Association, from Whangārei to Kaitaia was via Mangakahia and was named Highway 1.

Formerly administered by the Far North District Council and Whangarei District Council, in May 2015 the NZ Transport Agency agreed to include it to the state highway network after lobbying from the local authorities and industries given its significance to the regional forestry industry and its connectivity to the regions port near Marsden Point.

The route had its highway status revoked in December 2003, as part of the closure of Port Whangārei to commercial shipping and the opening of Northport at Marsden Point.

Six months later, in June 2004, SH 15A was gazetted to provide a highway link to the new port facilities at Marsden Point.

[7] SH 15A was created six months later, in June 2004, to provide a highway connection to the new site of the port at Marsden Point.