Factual error: In the scene in the church where Ian is being baptized, he is in black shorts. In the Greek Orthodox Church, he would be required to wear white when being baptized.
Factual error: When Toula and Ian are standing on the bridge talking about their families, you can see the Toronto skyline in the background (Scotiabank, Bank of Montreal), although they are supposed to be in Chicago.
Factual error: In the scene where Toula removes the 'Computers and Tourism' flyer from the bulletin board, there is another flyer in the top left of the screen advertising the 2001 Class of Ryerson. Ryerson University is located in Toronto, while the movie is supposed to be set in Chicago. (01:11:05)
Factual error: When Toula's grandma is being shown the house, she starts to tell Gus off. The captions show that she says "Listen here, ugly Turk, . . ." but in fact she says, "Listen here, I KNOW YOU'RE A TURK, . . ." (00:06:30)