Pinehurst is an unincorporated village and census-designated place in the town of Billerica, Middlesex County, Massachusetts, United States. The population was 7,368 at the 2020 census. It is in the southeastern part of town along Massachusetts Route 3A. Pinehurst's zip code is 01866 and is for mail delivery to the Pinehurst PO Station only. Home and office mail delivery in Pinehurst must use the Billerica, MA zip code.