Britton Municipal Airport (IATA: TTO, ICAO: KBTN, FAA LID: BTN) is a city-owned, public-use airport located two nautical miles (3.7 km) northeast of the central business district of Britton, a city in Marshall County, South Dakota, United States. According to the FAA's National Plan of Integrated Airport Systems for 2009–2013, it is categorized as a general aviation airport.

Although many U.S. airports use the same three-letter location identifier for the FAA and IATA, this airport is assigned BTN by the FAA and TTO by the IATA (which assigned BTN to Marlboro County Jetport in Bennettsville, South Carolina).