- In "The Legend of the Gobblewonker," Dipper asks Mabel if they got pictures of the gnomes from "Tourist Trapped." She did not, but she kept some beard hair.
- The "S" letter in the Mystery Shack's sign gets cut off in "Headhunters" by Sherlock Bleeding Holmes, it stays that way onwards.
- In "The Hand that Rocks the Mabel," Dipper apologizes to Toby Determined for accusing him of murder in "Headhunters".
- In "Dipper vs. Manliness," Mabel shows off her scrapbook. One picture is of the beheaded wax statue of Stan from "Headhunters."
- In "The Time Traveler's Pig," the pilot of the wagon on the Oregon Trail exclaims "By Trembley!" referring to Quentin Trembley, who previously appeared in "Irrational Treasure."
- In "Carpet Diem," Waddles can be seen wearing the top hat Quentin Trembly gave to Mabel in "Irrational Treasure."
- In "Boyz Crazy," Dipper sees Mabel dancing happily and assumes she ate Smile-Dip again. Smile Dip had previously given Mabel a psychedelic trip in "The Inconveniencing."
- In "Boyz Crazy", Mabel tears apart the picture she took with Candy & Grenda. It's shown taped back together in later episodes.
- In "Bottomless Pit," Deputy Durland asks Stan to teach him to read, confirming Mabel's insinuation that he couldn't from "Irrational Treasure."
- In "Gideon Rises," we see Bud with the clown painting that Stan stole from him in "The Hand That Rocks The Mabel."
- The "Fixin' It with Soos" shorts show that Soos is still living in the now cleaned-up extra room that Dipper and Mabel found in "Carpet Diem".
- In "Scary-oke" there's a mug that says "#2 Boss" that's on Mabel's nightstand, referencing the events of "Boss Mabel."
- In "Into The Bunker":
- Dipper remarks that zombie movies are a lot less scary when you've fought actual zombies, which he did in "Scary-oke."
- Wendy says towards the end that if Dipper ever stopped being her friend, she would throw herself into the Bottomless Pit, to which we were previously introduced in "The Bottomless Pit."
- In "Sock Opera," upon seeing Gabe, Mabel comments that she was just getting over Mermando, her previous crush and the one she shared her First Kiss with in "The Deep End". Dipper, unimpressed, responds that he didn't care for him.
- In "Society of the Blind Eye," Mabel sees a poster for one of Gabe's puppet shows, and tears it down. Behind it is a poster for Sev'ral Timez from "Boyz Crazy."
- Also in that episode, we see footage of the Society erasing Robbie's memories of the events of "Fight Fighters."
- In "Soos and the Real Girl":
- Dipper says that bringing a video game character to life can bring nothing but trouble, citing his own experience with Rumble McSkirmish in "Fight Fighters." Rumble himself has a cameo in the same episode.
- While flirting with a girl who's eating meat, Soos mentions that he was in a pig's body once, recalling "Carpet Diem."
- In both "Blendin's Game" and "The Love God," Stan can be seen wearing the bandage he put on when he hurt his hand during the credits in "Society of the Blind Eye".
- In "Boss Mabel," Wendy marks up the price of the snow globes in the Mystery Shack, from 2 dollars to 200 dollars. In "Soos and the Real Girl," they are still marked at 200 dollars.
- "The Last Mabelcorn": Mabel says Dipper has been paranoid about Bill Cipher since he turned him into a sock puppet, referring to "Sock Opera".
Continuity Nod / Gravity Falls