After Sam and Tess meet, he crumples the paper he is holding and drops it into an ash can. When it falls into the can, it is not wadded up.
The position of the mixing bowl in relation to the waffle iron changes between shots.
In the first scene in the bar, in which all are listening to the NBC Radio program "Information, Please", the dial of the AM radio on the shelf behind the bar changes location between long shots and close-ups. It is correct in close-up, at 660kHz, one of the broadcast frequencies NBC used in New York City in the 1940s; at 880kHz, in long shots, the frequency is of the New York City CBS affiliate.
When Sam enters Clayton's office, Tess is adjusting her skirt on the left leg side and then, in the close-up, looks at him with a curious gaze followed by a pout of the lips. In the following long shot after Sam begins to leave and re-enters, she is now adjusting the skirt on the side of the right leg and repeats the exact same facial gestures.
When Sam and Tess enter Pinkie's bar and they are listening to "Information Please," in some shots Sam is eating a full dinner along with coffee, while in other shots, he is eating peanuts along with an alcoholic beverage.
In the kitchen scene, Tess uses a vacuum coffee maker (Cona) to make coffee. However, if she had put the coffee in the bottom of the coffee maker and the water in the top, as shown, it wouldn't have made coffee at all.
During the baseball game near the start of the film, the Yankee first baseman is shown wearing uniform #8. In reality, Bill Dickey, a catcher, wore #8 for the 1942 Yankees. His number was retired, along with his successor Yogi Berra (also #8), in a joint ceremony on July 22, 1972. As of 2022, this is the only time two different players for the same team in the same position have had their uniform numbers retired.
When Tess gets out of the car when she arrives at her parents' house, she shuts the car door, and a reflection of a man's legs standing and watching can be seen, even though there's no one else in the shot.
During the discussion of the "sparrows/lovebirds" in Tess's office, as Tess moves out from behind the desk a boom mike shadow is visible in the upper right corner.
When Sam and Tess come home to Tess's place after a night of drinking at Pinkie's, the shadow of the boom mike can be seen following them across the wall at the top of the screen.
When Sam moves in to Kiss Tess goodbye at the airport, the camera zooms in for a closeup. When it does, you can see the shadow outline of the camera pulling in on Sam's back.
When Chris, the little Greek refugee, says goodbye as Sam and Tess are leaving for the evening, he says, 'Kah-lee meh-rah," which is Greek for "Good morning," not "Good night."
When Sam goes to Mr. Clayon's office Gerald, the male receptionist tells him that she's waiting for him and Sam says a neutral "thanks" without showing a reaction. However, the receptionist should have said "he" instead of "she" because Sam had no knowledge that Tess was in the office and was surprised when he saw her.
When Sam and Tess are being read their wedding vows, the Justice of the Peace uses the incorrect word "invested" instead of the correct term "vested".
When Sam argues with Tess after returning from Chicago, he tells her that she could have contacted him at the press box in Soldiers' Field. The correct name of the Stadium is Soldier Field.