Hainesville is an unincorporated community located within Sandyston Township, in Sussex County, New Jersey, United States.

It is adjacent to the Delaware Water Gap National Recreation Area, and near the towns of Shaytown and Layton.

[2] Named for Daniel Haines, governor of New Jersey from 1843 to 1844 and from 1845 to 1848,[3] it is in Area code 973, and ZIP Code 07826, both of which it shares with Branchville, New Jersey.

[6] The Catholic parish St. Thomas the Apostle is actually located in nearby Layton.

[7] People who were born in, residents of, or otherwise closely associated with Hainesville include: