Combat 18 was a neo-Nazi organization formed in the United Kingdom in 1992 that oversaw cells in several countries including Canada. Combat 18 cells were known for engagement in Hooligan culture, organized brawls, street violence, and distributing white power music. Though most Combat 18 cells are defunct, groups that originated as Combat 18 cells in countries including Poland and Ukraine may still be active.

Combat 18 was designated as a terrorist entity in Canada in 2019 along with associated group Blood and Honour.