The 24-year-old actor and comedian and 25-year-old singer said they plan to take a hiatus from the photo-sharing site due to "negative energy" online.
Davidson explained his decision in an Instagram Stories post Monday after deleting photos of Grande and all of his other posts on Instagram.
"no there's nothing wrong. no nothing happened. no there's nothing cryptic about anything. i just don't wanna be on instagram anymore. or on any social media platform," the star wrote.
"the internet is an evil place and it doesn't make me feel good," he said. "why should i spend any time on negative energy when my real life is [expletive] lit. the fact that i even have to say this proves my point. i love you all and i'm sure i'll be back at some point."
Grande shared similar sentiments in a tweet to fans Tuesday, saying she will use Snapchat in the interim.
"yeh! i'm prolly gonna post on der for a little while & take a breather from twitter & ig for a little," the singer wrote.
"just sometimes can't help but bump into some negative [expletive] that really can bum u out and it's not worth it honestly," she explained. "promised i'd always tell you. i love u sm! be well & happy."
Davidson and Grande confirmed their engagement in June after a few weeks of dating. Davidson gushed about his fiancee in a since-deleted post on her birthday June 26.
"happy birthday to the most precious angel on earth! you're my favorite person that ever existed :) i love you sm," the Saturday Night Live star wrote.