In the 1950 U.S. Census, Phillipsburg was part of the census-defined Unionville-Phillipsburg unincorporated place with population of 2,770. In the 1960 U.S. Census, the two communities were separated with Phillipsburg listed as an unincorporated place with a population of 2,037. Phillipsburg was redesignated as a census designated place in the 1980 U.S. Census.
In the 1950 U.S. Census, Phillipsburg was part of the census-defined Unionville-Phillipsburg unincorporated place with population of 2,770. In the 1960 U.S. Census, the two communities were separated with Phillipsburg listed as an unincorporated place with a population of 2,037. Phillipsburg was redesignated as a census designated place in the 1980 U.S. Census.