[2] In December 2010, at the age of 18, Kollmats signed with Kopparbergs/Göteborg FC in the Damallsvenskan, the top division of women's soccer in Sweden.
In April 2013, Göteborg defeated 2012 Damallsvenskan champions, Tyresö FF to clinch the Swedish Supercup.
[6] In August of that year, Kollmats suffered a cracked rib after colliding with goalkeeper Kristin Hammarström.
[10] In September 2018 Kollmats endured a difficult game against Hammarby, scoring two own-goals in Göteborg's 2–1 defeat and then being carried off with concussion.
[12] Kollmats returned to Sweden to play with Djurgården in July 2023 after one and a half year in Roma.