Factual error: Periodically Indiana's "DMV" is mentioned, however, unlike most states, Indiana has a 'Bureau of Motor Vehicles' (BMV), not a 'Department of Motor Vehicles' (DMV).
Continuity mistake: The kitchen in April and Andy’s house is open and a joint room with their living room. They were in a closed off different kitchen in the episode where they get married.
The Reporter - S1-E3
Continuity mistake: They eat at JJ's Diner and the waffles are square. Throughout the remainder of the show, at JJ's Diner, the waffles are round. Unlikely they'd switch their waffle iron from square to round. Also, the old retired waffle iron Ben and Ann get Lesley is round. (00:03:20 - 00:16:10)
Revealing mistake: When April is searching for Donna Meagle on "iGoogle" you can see that it is a HTML document that they've most likely made themselves. The URL says "C:\User\pnr\Desktop\igoogle\igoogle search\donna.HTML". You can also see that the internet browser says "Google Search" but they've used "iGoogle" everywhere else. (00:04:30)
Continuity mistake: When volunteering with Kaboom, Leslie says they are building in Eagleton, which she describes as "two towns over." As the show continues we visit the Eagleton/Pawnee border and the neighboring towns become a plot point for many episodes. (00:01:35)
Factual error: Leslie mentions that Eagleton is "2 towns over." We in later episodes see the border wall between them (S3E12), indicating they're right next to each other.
The Set Up - S2-E13
Continuity mistake: As they are celebrating April becoming an assistant, her drink is dark red (probably wine) and in the next shot suddenly becomes a bubbly yellow (probably champagne), and in the next shot turns back into a red liquid. (00:20:55)
94 Meetings - S2-E21
Plot hole: April tells Ron that she's always known that he's Duke Silver because her mom has all his albums. So why didn't her mom freak out when Duke Silver appeared on her doorstep or, if she somehow didn't realize that Ron is Duke, even mention the resemblance? (00:20:35)
Continuity mistake: When Leslie throws Jerry's Painting into the lake, the painting is seen still on the easel when they show Jerry with his hands on his head. (00:02:20)
Continuity mistake: When they're in the club, Leslie is dancing facing away from Chris and Ann, but in the next shot, she's facing towards them.
Fancy Party - S3-E9
Continuity mistake: When Ron is groaning about his tooth pain, the camera cuts at different angles. Leslie's mug moves from the table to her hand in two shots.
The Treaty - S4-E7
Revealing mistake: Tom is talking on the phone in Ron's office. When he turns the phone at an angle the call home screen that has the end button, the speaker button, etc. turns to its side, which means it was a picture - he wasn't actually calling anyone. (00:02:25)
The Treaty - S4-E7
Factual error: At the UN conference, 'England' is shown as a member of the Security Council. England sits on both the UN and the Security Council as part of the 'United Kingdom' - not as a stand-alone country. UN nerds Leslie and Ben would have known this.
Campaign Ad - S4-E12
Continuity mistake: When Chris is talking to Ron in his office, he accidentally hits the gun on the corner of the desk causing it to rotate. When the next shot is taken, the gun has returned to its normal position. (00:04:25)
Continuity mistake: When Ben and Leslie approach the commissioner about the recount, there are two guys sitting down behind Jen. The camera follows the commissioner leaving the room and then momentarily shows Leslie and Ben. As Jen is lying out on the table the two guys have now disappeared. (00:13:00)
Continuity mistake: Andy is explaining that he wanted his coworkers to steal something from him so he can practice his investigating skills. In one shot his sunglasses are hanging at the middle of his torso and when it cuts to a closeup and back out the sunglasses have magically traveled up to his neck as he exclaims "did you guys steal my sunglasses too?" (00:15:00)
Visible crew/equipment: When Dianne's daughters have locked themselves alone in the room, just as Jerry is about to put the keys in the door to unlock it so they can prevent the girls from cutting their hair, the boom microphone dips into view in the room where the girls are alone. This boom mic is not from the "documentary" crew. (00:13:25)
Article Two - S5-E19
Character mistake: During Garth's Filibuster, the Marvel characters come into the Star Wars universe because Thanos is using the Infinity Gauntlet's Reality Gem to cross realities. The gem allows the wielder of the Gauntlet to MOLD reality to his desire, but an Infinity Gauntlet does not work outside it's home universe/dimension, so Thanos wouldn't be able to "jump from different realities" with it. Someone that well-versed in the Marvel Comics universe would know this.
Continuity mistake: Jerry is saying goodbye to all in the office and is carrying a box with his things to take with him. In the box is a tall flag that keeps disappearing and reappearing between shots. (00:01:10)
The Pawnee-Eagleton Tip Off Classic - S6-E3
Continuity mistake: When Ingrid and her team show up late to the meeting at City Hall, as Ingrid takes a seat we see under the table that the actress is wearing dark sneakers, but Ingrid is wearing off-white heels when she enters and exits. (00:08:25 - 00:11:25)