The club emerged in the late 1940s, when the inhabitants of Viipuri had mostly been relocated in Lahti, after evacuation during World War II.

However, by 1996 the club was in financial difficulties, and the problem was solved by merging Reipas and they more recently arrived local rival Kuusysi.

At the time both clubs played in the northern section of the second-tier Ykkönen, but at the end of the season Reipas found themselves in the relegation zone.

[1] The new club was simply called FC Lahti, and it inherited Kuusysi's place in Ykkönen.

The divisional position and the league license of Reipas, in 1997 Kakkonen, was given to FC Pallo-Lahti, which was founded as a reserves team.