Audio/visual unsynchronized: When we hear Andrew's friend yell down to him from the airport tower, "There was nothing I could do," his mouth doesn't move.
Errors in geography: A time-lapse scene shows the sun not setting during the night at Sitka. Alaska is almost 1500 miles north to south. While there are places in Alaska, above the Arctic Circle, where the sun doesn't set at night in summer, the sun always sets in Sitka, even in summer (though sometimes quite late, and nautical twilight isn't reached every night).
Incorrectly regarded as goofs: Granny Annie who is celebrating her 90th birthday says she wore the wedding dress when she was pregnant, but also says her mother made the dress in 1929. She would have been ten years old in 1929. However, she never actually said she wore the dress in 1929.
Continuity: After Margaret (Sandra Bullock) spits out the hors d'oeuvre she was forced to eat, the camera goes to Andrew (Ryan Reynolds). The next shot of Margaret you can see the side of her face, and she is cracking up. She walks into the next scene very serious.
Continuity: During the sequence where Margaret proposes to Andrew on the street in New York, the same woman in a green sweater walks by three times.
Continuity: When Margaret is forced to propose to Andrew on the street, a man in a white t-shirt with sunglasses can be seen walking by several times in the background.
Errors in geography: Early scene - bedtime - shows sun's movement to indicate location within Arctic Circle, but the sun angle in subsequent scenes could only occur at much lower latitudes.
Continuity: When Margaret proposes to Andrew, a white truck displaying the words 'DEE-DEE' (parked up behind the Fed-ex truck) completely vanishes between shots.
Errors made by characters (possibly deliberate errors by the filmmakers): When Margaret and Andrew go to get a "fiancée" visa, they go to the United States Citizenship and Immigration Service (USCIS) office in New York. However, on the plane flying to Sitka, Andrew refers to a list of questions that "INS" will ask. INS (Immigration and Naturalization Service) no longer exists; USCIS is one of the three agencies that now have the functions the defunct INS had.
Errors made by characters (possibly deliberate errors by the filmmakers): After the naked scene, when Margaret is telling Andrew about herself, she says she took disco lessons in "the sixth grade". Canadians say "grade 6".
Revealing mistakes: When Margaret and Andrew are in her office, a view out the window shows the barren trees in the courtyard at (at international Place in Boston, since that part was filmed in late winter/very early spring) but yet the same weekend they are in in Alaska where everything is lush green, even though Alaskan Spring is far behind Boston and NY Spring.
Factual errors: The only scheduled commercial air service between Juneau and Sitka is done by Alaska Airlines. They'd be on a 737 and not the twin-engined propeller-driven plane shown.
Errors in geography: There are no lobster boats in Sitka's harbors.