The stars shared pics from their beach date on Sunday.
The actors -- who star as John B and Sarah Cameron on the Netflix teen drama -- headed out for a beach date, and Stokes shared a pair of pics from the outing.
"Cats outta the bag," Stokes, 27, wrote, alongside a photo showing Cline sitting next to him on a beach blanket.
Cline, 22, adorably commented on Stokes' post, first writing "Topper punching the air rn" -- a reference to her on-screen boyfriend in Outer Banks. She then added, "I've fallen and I can't get up."
Fellow co-star Jonathan Daviss also commented on Stokes' pic, sharing, "Well it’s about time ❤️❤️❤️."
Stokes and Cline, who were first romantically linked back in April, are also dating on-screen in the hit teen mystery drama.
In April, Stokes talked to ET about the show's season one cliffhanger, which saw John B. and Sarah fighting for their lives in the middle of the ocean.
"It's cool because depending on what happens, it leaves the entire world of Outer Banks to what could happen next," said the actor, who has also appeared on Stranger Things. "Which is fun -- not just for us as actors, who had the opportunity to kind of explore what could be, but now we know where the gold is, so I think it's an exciting time to give it to the world and say, 'What are John B. and Sarah really going to get into now?' We thought it was dark and dirty then, but it's gonna get real."
'Outer Banks' Stars Chase Stokes and Madelyn Cline Break Down That Finale and Tease Season 2 (Exclusive)