The first mentions of Suolahti are from the 16th century but the name became stable describing a population of 100-150 village residents in the end of the 19th century. The village before that was known as Paadentaipale. The opening of the railroad in 1898 industrialized Suolahti and increased the waterborne traffic on Keitele, for which Suolahti provided a railway harbour at its south end. The same year, a steam-mill started operating which was soon followed by other industrial facilities. This sped up population growth and urban development. In the first three decades of the 20th century, the population increased to two thousand. It gained town status in 1977.

Prior to a 2007 consolidation with Sumiainen to make Äänekoski, Suolahti was twinned with:

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