Horizon League
NCAA conferences often have one or more "associate" members that play only a limited number of sports in the conference, usually one. For most of its history, the Horizon League has not had associate members. The first such member was Belmont, which was a men's soccer member from 2014 to 2018. More recently, the Horizon greatly expanded its men's tennis league. The Ohio Valley Conference (OVC) merged its men's tennis league into the Horizon in 2022. At the same time, Belmont returned to the conference for men's tennis, and Chicago State moved men's and women's tennis into the Horizon.