Since the first election to the council in 1973 political control of the council has been held by the following parties:
Non-metropolitan district
Unitary authority
Stockton-on-Tees Borough Council election, 1973Stockton-on-Tees Borough Council election, 1976Stockton-on-Tees Borough Council election, 1979 (New ward boundaries)Stockton-on-Tees Borough Council election, 1983 (Borough boundary changes took place but the number of seats remained the same)Stockton-on-Tees Borough Council election, 1987Stockton-on-Tees Borough Council election, 1991 (Borough boundary changes took place but the number of seats remained the same)Stockton-on-Tees Borough Council election, 1995Stockton-on-Tees Borough Council election, 1999Stockton-on-Tees Borough Council election, 2003Stockton-on-Tees Borough Council election, 2005 (New ward boundaries increased the number of seats by 1)Stockton-on-Tees Borough Council election, 2007Stockton-on-Tees Borough Council election, 2011Stockton-on-Tees Borough Council election, 2015