Blackwells Mills is an unincorporated community and census-designated place (CDP)[7] located in Franklin Township in Somerset County, in the U.S. state of New Jersey.

[11] Blackwells Mills is on the east side of the Millstone River in Franklin Township, Somerset County, New Jersey.

William Blackwell built a fine Federal period house on the land across the road on the Hillsborough side.

Following the death of William Blackwell in the 1850s, his son John came into possession of the mill.

John Blackwell died early in life, and his widow sold the mill to Augustus VanZant in 1872.

[1][2] The 2010 United States census counted 803 people, 238 households, and 218 families in the CDP.