The United States Coast Guard Auxiliary is the uniformed, non-military volunteer component of the United States Coast Guard. Congress established the unit on 23 June 1939, as the United States Coast Guard Reserve. On February 19, 1941, the entity was renamed the United States Coast Guard Auxiliary. The Auxiliary's purpose is to bolster all USCG undertakings both at sea and in the sky, with the exception of tasks necessitating "direct" law enforcement or military actions. As of 2022, the U.S. Coast Guard Auxiliary boasted around 21,000 members.

The United States Coast Guard (USCG) is the maritime security, search and rescue, and law enforcement service branch of the United States Armed Forces and one of the country's eight uniformed services. The service is a maritime, military, multi-mission service unique among the United States military branches for having a maritime law enforcement mission with jurisdiction in both domestic and international waters and a federal regulatory agency mission as part of its duties. It is the largest coast guard in the world, rivaling the capabilities and size of most navies.