Whitinsville is an unincorporated village within the town of Northbridge in Worcester County, Massachusetts, United States. Whitinsville is a census-designated place and its population was 6,750 at the 2020 census. Whitinsville is pronounced as if it were spelled "White-ins-ville". It was founded by the Whitin family, after whom it is also named. It is a post …Whitinsville is an unincorporated village within the town of Northbridge in Worcester County, Massachusetts, United States. Whitinsville is a census-designated place and its population was 6,750 at the 2020 census. Whitinsville is pronounced as if it were spelled "White-ins-ville". It was founded by the Whitin family, after whom it is also named. It is a post office jurisdiction, with a ZIP Code of 01588. It is located on the Mumford River, a tributary of the Blackstone River.