The 34-year-old moves to the American registered team as John Degenkolb's wingman, with the pair among a raft of new signings as the team looks towards life after Fabian Cancellara's retirement.
De Kort, who bas been part of the Giant-Alpecin set-up since 2009, will add steel and experience to Trek-Segafredo's Classics line-up and joins as one of Degenkolb's chief lieutenants.
"Obviously I've been with this team for quite some time and it felt like it was the time in my career when I should look for a new challenge and a new environment," he recently told Cyclingnews.
"I've always had a good time on this team but I felt like it was the time to move on. That, and in combination with John Degenkolb, I didn't really have to think very long before accepting."
Degenkolb's move away from Giant-Alpecin was one of the worst kept secrets during the summer. Michael Matthews was known to be on his way to the team as far back as June, casting Degenkolb's future under a cloud of uncertainty. A number of teams expressed interest in the German's signature but Trek sealed the deal, offering the 2015 Milan-San Remo and Paris-Roubaix winner the chance to rebuild his career after a serious accident during a winter training camp.
Both Degenkolb and de Kort are strong friends, and the pair has raced together since 2012. Their strong bond helped carry de Kort to Trek.
"He asked me what I was thinking last year. He asked me what I wanted to do and if I wanted to re-sign or move on. I said I was open for anything and he said he would take that into consideration. Into this season he said we had a few opportunities, if I still wanted to join him. He wanted to take me with him because we work well together, and I spoke to the teams as well and we both had the best feeling with Trek."
Trek Segafredo's transformation ahead of the 2017 season has been stark. Cancellara, Ryder Hesjedal and Frank Schleck have all retired, while Alberto Contador has joined and Bauke Mollema re-signed. The team arguably have their most rounded squad in years.
"There are really big changes there," de Kort said.
"I've also been teammates with Alberto Contador before because of our time together at Liberty Seguros and Astana. In the Classics, that's where I'll target things. We've a really strong team there and I hope I can chip in as well. Also, in the sprints we've got some fast men."