Continuity mistake: Just before President Whitmore gives his rousing speech, when Major Mitchell is talking into the mic, asking for all flight crews to report to their designated areas, the camouflage pattern on his uniform is entirely different from the uniform he wears in the previous and following scenes that he appears in. (01:51:20 - 01:55:10)
Continuity mistake: When Steven walks across the lawn to get the newspaper, a few feet away from the window there is a tall rosebush behind a white bench seat with a high back. Later, when Steven packs up to head back to the base, Jasmine pulls open the curtains and right outside the window is a tall flowerless bush. (00:25:20 - 00:29:10)
Continuity mistake: When Jasmine sees the approaching fireball she grabs Dylan from the car and begins to run. In the shot from behind, there are double-yellow lines on the road at her feet reaching into the distance, but in the shot facing her the lines have vanished, though she did not change lanes.
Continuity mistake: At the White House, after the President says good morning to Connie and walks past her, she stands up then places the two folded sections of USA Today in her left hand - with the headline section covered, as she holds her briefcase in her right hand. Next shot from behind, she is now holding a section in her right hand with the briefcase, as she reads from the headline section held in her left hand.
Continuity mistake: In the briefing scene at El Toro prior to the first counter-offensive, Lt. Colonel Watson, the briefing officer, has silver oak leaves on his collar (Marine Lieutenant Colonel). A few scenes later, when El Toro is under attack, Lt. Colonel Watson is shown again, but has been demoted two grades and has two silver bars on his collars (Marine Captain).
Visible crew/equipment: On bended knee, when Jimmy opens Steven's gift box with the ring, in the close-up an oblong metallic object is pushing up against Jimmy's left hand, between his thumb and index finger. Likely used to keep his hand steady in the tight close-up. (Only visible on fullscreen DVD.) (00:35:20)
Continuity mistake: When President Whitmore boards the chopper and then Air Force One, he wears a white shirt with both thin and thick stripes. The stripes on his shirt collar constantly change, and nowhere is it more noticeable than when they arrive at Area 51. It varies between only one thick stripe, which changes from the top of the collar to the bottom, or two or more thick stripes, all surrounded by thin stripes. Wardrobe Dept bought identical shirts for the actor to wear, but the collar stripes just don't match up between scenes.
Continuity mistake: When Russell boards the F/A-18, he places the photo of his kids beside the left DDI on the instrument panel, which is to the left of the number key pad, below the HUD. When he says, "Payback's a bitch..." there is an upside-down matchbook cover (with the words, "Amraam armed....is off" scribbled on it) exactly where the photo was - beside the left DDI, but then later the photo reappears. Also note that the yellow/black zebra marker behind the photo becomes a blue marker as well. (02:09:10 - 02:13:30)
Factual error: When Russell enters his F/A-18 during the final assault, he pushes the keypad "8" button out of curiosity and it inadvertently arms a missile. In reality, the keypad buttons are merely for navigational purposes and map coordinates. They would never be tied to the weapons system. (01:59:15)
Revealing mistake: The following take place in F/A-18s. After Jimmy says, "I got you covered, big daddy," there is a close-up of his gloved hand as his thumb presses the launch button. Later, when President Whitmore fires his last missile (with negative impact) there is a close-up as his thumb presses the launch button, and then a minute later there is a close-up of Russell's hand as he presses the launch button (resulting in launch failure). The last two close-ups are the very same shot as shown earlier, only the last two shots are flipped the other way. (00:57:25 - 02:04:00)
Visible crew/equipment: After President Whitmore decides to go ahead with David's plan for the virus, he, Connie and Grey are walking when the President pushes Nimzicki up against a desk. Just before they reach that desk, the actor's mark is visible on the floor, precisely where the President stops before he fires Nimzicki. (Only visible on fullscreen DVD.)
Continuity mistake: When David is explaining to the President about the aliens' intentions with Earth's satellites, he draws two lines that start at the destroyer and go off straight both edging off Earth. But when he places the paper back on the desk to draw in the satellites, the left lines have risen away from the Earth. (00:41:00)