Factual error: It's mentioned that the British and New Zealanders turned the Americans away. This is untrue - the Americans stayed with both for a time until it was decided that they would be safer with the Canadians.
Factual error: In the scene where the Swissair 747 is taking off from Tehran the police cars keep up with the plane until it lifts off. Takeoff speed for a 747 is about 160 mph so the police cars would have been far behind by then. (01:41:40)
Factual error: Error in the Istanbul scene. Ben Affleck is shown entering what looks like the Blue Mosque in Istanbul. We are shown the outside and the courtyard of the Blue Mosque with its distinct blue rooftops. When Ben Affleck is meeting another dude inside, they are inside the building which now serves as a museum and which is known as "Hagia Sophia." (00:48:40)
Factual error: In the final scene where the Swiss Air 747 is taking off, the police cars are travelling right behind the engines of the jet. They would have easily been blown away by the engine. (01:41:15)
Factual error: They play a track "When the Levee Breaks" from a Led Zeppelin album. The hand shows the needle being placed at the next to last track on the album. However, "When the Levee breaks" is the last track on Led Zeppelin IV's second side. (01:18:30)
Factual error: In the beginning of the film, when Agent Mendez is called to CIA Headquarters, as he passes the secretary's desk, the outgoing letter propped against her word processor has two postage stamps affixed (2-cent Navajo necklace & 37-cent US Flag) which were first issued and then reissued by the US Postal Service beginning 2003-04, 23+ years after the hostage event in 1980. (00:14:10)
Factual error: The embassy takeover was November 3rd. A scene in Washington DC described as 69 days later showed Tony Mendez driving around town with yellow/fall like leaves on the trees, something that would not have been true in the middle of January. A similar scene at the end of the movie has Tony Mendez approaching his house in Virginia and a very fall like scene is shown. (00:13:45 - 01:49:00)
Factual error: As a newspaper from January of 1980 is displayed, the Rolling Stones song "Little T&A" is played. That song appeared on the "Tattoo You" album, which was not released until Aug. 24, 1981.
Factual error: CIA agent Mendez takes-off from Washington to Tehran, apparently via London because he boarded a British Airways flight, on a twin engine aircraft. Twin engine aircraft flights across the Atlantic were just being introduced by TWA around 1980 and weren't flown by BA until years later, if at all. Also, the BA Boeing 747 depicted had tail colors that were not introduced by the airline until the early 2000s. (00:46:35)
Factual error: The turbans worn in the scenes in Tehran are not the sort worn by Iranian clergy - they are wound incorrectly and are too flat.
Factual error: The interior shots of the Swissair 747 cockpit show a mockup. The window frames as shown are very wide and thick, but the real ones are much thinner. (01:39:55)
Factual error: The Swiss Air 747 in the movie had an extended upper deck. The first Swiss Air 747-300 did not fly until 1982, and didn't enter commercial service until 1983, well after the events of this movie.
Factual error: Iranian revolutionary guards didn't have caps with their uniforms until 1988 (after the end of the Iran-Iraq war).
Factual error: In 1980 the Canadian airport we see was called Dorval international airport, not Trudeau.