Pinehurst is an unincorporated village and a census-designated place (CDP) in the town of Billerica, Middlesex County, Massachusetts, United States. The population was 6,941 at the 2000 census. It is located in the southeastern part of town along Route 3A between the Shawsheen River and the Burlington town line. 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 (01821).