The singer made the announcement Tuesday with some help from Ellen DeGeneres and his future fellow coaches.
In a sneak peek from Tuesday's "Ellen DeGeneres Show," Jonas seemed reluctant to make the reveal he'd been teasing on Twitter, so the host rolled a clip that made the reveal for him.
The video showed Blake Shelton, Kelly Clarkson and John Legend each welcoming the 27-year-old to the talent competition in their own way. For instance, both Clarkson and Legend suggested an alliance with the newcomer.
And Shelton? He wasn't so sure about the new development.
"I'll have to look through the rules because this is my TV show, and I'm not sure you're even old enough to be a coach on 'The Voice.' But I'm certain that you're going to get your butt kicked, buddy," Shelton said.
With that brief message, a new "Voice" rivalry was born. "Blake, I'm going to kick your ass," Jonas promised.
He got an extra incentive to do just that when DeGeneres dished up one of her signature scare pranks for the star, wherein a Shelton lookalike jumped out of a table and scared Jonas.
But the other coaches might want to watch out, too!
After his visit to Ellen, Jonas took to Twitter again, and Shelton wasn't the only one to get a word of warning.
"Well, the big news is finally out," he said. "I am so excited — season 18 of 'The Voice.' To be joining that crew of amazing coaches — Kelly Clarkson, John Legend, Blake Shelton — while I'm excited to work with you guys, I'm coming for you. I'm hoping for a season-one win for Team Nick."
If you ask his biggest fan, he's already got it in the bag.
"I think Nick just needs to be himself, which he's going to (be)," his wife, actress Priyanka Chopra, told TODAY Tuesday morning. "He knows about music so much. He's literally been a music prodigy since he was 7 years old. ... Blake, you better watch out!"