FC Thun was founded on 1 May 1898 by a group of football enthusiasts who met at the Gasthof Zum Sternen, at the corner of Marktgasse and Schwäbisstrasse in Thun. The club adopted red and white as its colours and spent its early decades working through the ranks of amateur football, from the Central Swiss League through the 2.Liga from 1933, before a league restructuring in 1944 moved the side into the 1.Liga. The club's first-ever promotion to the top flight, the Nationalliga A, came in the 1953/54 season after finishing runner-up to Lugano, but the stay lasted only a single campaign before relegation followed.
It took 47 years for FC Thun to return to the top division, finally achieved under coach Hanspeter Latour, who guided the club back to the Nationalliga A in 2001/02. A few seasons later came the brightest chapter of the club's pre-2025 history: the run to the UEFA Champions League group stage in 2005/06, featuring current head coach Mauro Lustrinelli as the team's striker, Nelson Ferreira scoring in the memorable match against Arsenal, and Andres Gerber, today the club's chairman, wearing the captain's armband.
FC Thun play their home matches at the 10,000-capacity Stockhorn Arena. The club has twice reached the Swiss Cup final, losing in 1955 and 2019, and in 2025/26 it crowned more than a century of steady, community-rooted development with its first Swiss championship.