Sepp Kuss began his road cycling career with Gateway Harley Davidson - Trek U25, now Gateway Devo Cycling Team, in 2016 after a successful start in cycling on the mountain bike side. Sepp quickly showed what he was capable of, winning a stage of Redlands Classic, and a strong performance at Tour of the Gila. After Gila, Sepp went on to ride for Rally Cycling, before signing with World Tour team Jumbo-Visma. Since then, Sepp has won multiple World Tour stages, including stage 15 of the 2021 Tour de France. He has been Jumbo's Primoz Roglic's lieutenant, or super-domestique, in a number of Roglic's general classification triumphs.