NJSIAA for the 2019–20 school year as Group III for most athletic competition purposes, which included schools with an enrollment of 761 to 1,058 students in that grade range. The football team competes in Division 4 of the Big Central Football Conference, which includes 60 public and private high schools in Hunterdon, Middlesex, Somerset, Union and Warren counties, which are broken down into 10 divisions by size and location. The school was classified by the NJSIAA as Group IV North for football for 2018–2020. In the 07–08 school year, Colonia High School introduced three new sports: volleyball (boys and girls), ice hockey and swimming. The school has operated as the host school / lead agency for a cooperative ice hockey program with John F. Kennedy Memorial High School and Woodbridge High School, under an agreement scheduled to expire at the end of the 2023–24 school year. The girls bowling team won the overall state championship in 1981. The boys' bowling team won the overall state championship in 1984 and won the Group II title in 2012. Dagmara Wozniak was the state sabre champion in 2005. The boys basketball team won the 1985 Central Jersey, Group III Sectional Championship beating Franklin High School 53-51 in the finals. The team won the 2007 North II, Group III state sectional championship, edging Union Hill High School 84–83 in the tournament final. In 2008, the Patriots won 61-57 in the state semifinals against Rahway High School, the seventh-ranked team in the state, before losing 59-39 to Scotch Plains-Fanwood High School in the North II Group III finals to finish their basketball season with a record of 22–7. In 2018, the team won the 2018 North II, Group III state sectional championship, with a 57-33 victory over West Morris Central High School. In 2022, the team won the North II Group III sectional championship, defeating South Plainfield High School by a score of 56-52 in double overtime in the finals. The Patriots finished the season 25-5 and their second sectional title since 2019 in their third straight appearance in the sectional championship. In 2015, the football team finished the season with an 11–1 record and went to the North II, Group III state sectional championship before losing to Phillipsburg High School in overtime by a score of 28–21 in the tournament final. In 2020, John Poznanski won the individual NJSIAA state wrestling championship in the