On August 29 and 30, 2015, Sondre Ringen started for the first time in two competitions in Szczyrk, Poland, in the FIS Cup , where he finished 33rd and 40th. After further starts in the FIS Cup, he made his debut a good one and a half years later on March 11 and 12, 2017 in Zakopane in the Continental Cup , where he once achieved 18th place and thus also his first Continental Cup points and was disqualified in the second competition has been. This was followed by further starts in the Continental Cup.
In December 2017, wrestling won its first FIS Cup competition in Notodden . He also started in the Continental Cup in the 2017/18 season . At the competition in Titisee-Neustadt on January 7, 2018, he surprisingly took third place and thus his first podium in the Continental Cup. Three weeks later he finished second in the competition in Sapporo , where he was only 0.2 points behind Robert Kranjec in first place.
In his World Cup debut as part of the national group in the Raw Air Jumping on March 13, 2018, he reached the second round and got his first World Cup points with 22nd place.