Odermatt comes from Buochs in the canton of Nidwalden and is a graduate of the sports school in Engelberg . As a 16-year-old he began to take part in national junior races and FIS races in November 2013 . He started in all disciplines, where he was strongest in giant slalom and super Gs. In January 2015 he took part in the European Youth Olympic Festival in Malbun , where he took fourth place in the giant slalom. The first European Cup appearances followed in December 2015.
At the beginning of February 2016, Odermatt took part in a number of Nor-Am races in North America and finished second in the giant slalom at Mont Sainte-Anne . A few weeks later he won the gold medal in the same discipline and the bronze medal in the Super-G at the 2016 Junior World Championships in Sochi . As a junior world champion, he was eligible to take part in the World Cup final in St. Moritz , where he finished 22nd on March 19, 2016, for which, however, there were no World Cup points. At the end of the season, the Swiss giant slalom junior championship was added.
At the beginning of the 2016/17 season, Odermatt was nominated for the World Cup giant slalom on October 23, 2016 in Sölden . With the high starting number 53, he surprisingly finished 17th and won World Cup points for the first time (after the 1st round he was even classified in intermediate 12th). After the European Cup giant slalom in Val-d'Isère on January 18, 2017, Odermatt was diagnosed with meniscus damage, after which he had to take a break for the rest of the season. In March 2017 he was named Young Athlete of the Year by Swiss Sports Aid .
In the winter of 2017/18, Odermatt achieved several podium finishes in the European Cup, including one victory. At the 2018 Junior World Championships in Davos , he won five gold medals: in downhill, super-G, giant slalom, combined and team competition . With that he set a new record: no one had won five gold medals at the same Junior World Championship before. With a total of six gold and one bronze medal, he is behind Henrik Kristoffersen the most successful ski racer at junior world championships. Odermatt was not able to classify a single time in six appearances in World Cup giant slaloms, but as a junior world champion it was still eligible for the World Cup final in Åre . There he surprised with 11th place in the Super-G and 12th place in the downhill.
On December 8, 2018, Odermatt made it into the top ten in a World Cup race for the first time and placed 7th in the giant slalom in Val-d'Isère . He achieved his first World Cup podium on March 9, 2019 with third place in the giant slalom in Kranjska Gora , with the fastest time in the second run. On December 6, 2019, he achieved his first World Cup victory when he won the Super-G from Beaver Creek . Two weeks later, Odermatt finished the giant slalom in Alta Badia in fifth place; however, while driving, he tore the outer meniscus in his right knee. He recovered unusually quickly from the subsequent operation and only took part in the Super-G in Kitzbühel one month later , which he finished in 13th place. At the end of February, the next podium result followed in the Naeba giant slalom .