- Actor-Shared Background: Jay's story of how he and Silent Bob finally sobered up parallels that of Jay's actor Jason Mewes, including being arrested for driving around with a deployed airbag and spending six months in rehab.
- Awesome, Dear Boy: Rosario Dawson claimed in the DVD extras that the biggest draw for her was getting to see a (simulated) donkey show. note
- The Cast Showoff: Rosario Dawson's dancing, and to a lesser extent, Jay's.
- Directed By Castmember: The shot of the cup scooping ice from a urinal was directed by Jason Mewes.
- Enforced Method Acting: When filming the last shot, Kevin Smith had the Soul Asylum song "Misery" cued up on a boom box off-camera to fit the mood when the film goes back to black-and-white. Jeff Anderson actually screwed up the first take because it made him start crying.
- Harpo Does Something Funny: A rarity for a Kevin Smith movie, Wanda Sykes and Earthquake improvised all of their dialogue while waiting in line prior to the infamous "Porch Monkey" scene.
- Production Posse: Ben Affleck, Jason Lee, Ethan Suplee, and of course Brian O'Halloran and Jason Mewes.
- Real-Life Relative: Kevin Smith's daughter Harley Quinn Smith is the little girl that Dante waves to in the window of the restaurant. His mother also reprises her role from the first film as the milkmaid.
- Sequel Gap: 12 years since Clerks (1994 to 2006).
- Throw It In!: Gawking Guy was originally supposed to just roll his eyes and walk away when Dante and Emma started making out on the counter. The character's one line, "That's not very hygienic", was ad-libbed by Ben Affleck.
- What Could Have Been:
- Bob Weinstein wanted "Pillowpants" to turn out to be real, but ultimately decided that was too silly when Smith explained why it was funnier the way it was.
- With the very slim chance that Pillow Pants was actually going to be filmed, he would have been played by Jason Mewes dressed up as a troll and standing in front of a giant wooden labia. Allegedly, despite liking the final result, Jason Mewes was disappointed he did not get to take home a wooden labia.
- Before Rosario Dawson was cast as Becky, various others were considered, including Ellen Pompeo, Jennifer Schwalbach (who would play Emma) and Sarah Silverman, who apparently said to Smith "Let me play Randal and I'll do it for free."
- Smith recorded a podcast for fans to download onto their iPods and listen to in the theater in real-time with the movie like a DVD Commentary. The idea was abandoned, but the podcast appeared as an Alternate DVD Commentary.
- Originally Matt Damon was supposed to play Lance Dowds. However, Damon was also filming The Good Shepherd at the same time and couldn't make it. So Jason Lee took over the role during a day off from My Name Is Earl.
- Smith, being a big fan of Arrested Development, wanted David Cross to play the role of the Hobbit Lover. Cross showed interest, but had to decline due to scheduling conflicts. Based on a suggestion from Producer Scott Mosier's wife, Smith and Mosier offered Kevin Weisman the role and he accepted.
- Smith's original idea for the film had Randal and Dante working at New Jersey's famous Seaside Heights Boardwalk. Smith changed it to a fast food restaurant when filming at the boardwalk proved to be too expensive.
- Alec Baldwin, who voiced Leonardo Leonardo in Clerks: The Animated Series, was approached to make a cameo as Randal's father in the film's beginning.
- Working Title: Clerks 2: Hardly Clerkin' and The Passion of the Clerks.
Trivia / Clerks II