The filmmakers tried to use artificial flowers as often as possible because Debra Messing is allergic to real flowers.

The movie was originally going to be called "Something Borrowed".

Amy Adams dyed her hair blonde in this film.

Debra Messing, Dermot Mulroney, Holland Taylor, and Amy Adams are the only Americans in this film.

Based on the book "Asking for trouble" by Elizabeth Young.

Continuity

In the bedroom, Nick takes his blue shirt off three times.

After a confrontation with all of her family and friends, Kat walks away into the rain, dropping two wine bottles. In the next shot, the wine bottles have disappeared, and the lawn behind her is empty.

On the night Kat comes back and has her fun with Nick and they proceed to move to the boat in the driveway, they are seen standing and walking around inside. From the outside, the boat obviously is not large enough for that to happen.

When they first walk into the drinks reception, Kat's coat is flowing open, revealing the red dress she has finally chosen to wear after changing at the pub. They walk in and meet Aunt Bee, but when they turn around; her coat is fully buttoned and tied at the waist.

When Kat and Nick get on the boat, Kat's hair is mussed, but as soon as she takes off her shirt, her hair is perfectly in place. Clearly, if it was mussed before, taking her shirt off should not make it better.



Factual errors

As noted, there are no Virgin Atlantic flights from New York that arrive in London at 4:20 pm, but even if there was, it would have to leave NYC in the early hours of the morning; it clearly is daytime when Kat goes to the airport.

When Kat and Nick are approaching London, there is an announcement being made indicating the final decent into London. The woman on the PA says that the local time in London is 4:22 PM. Virgin Atlantic does not have flights from New York to London that arrive in the afternoon, only late at night or early morning.

Kat repeatedly withdraws ?250 from the ATM but receives only ?20 notes. It's not possible to make up ?250 from only ?20 notes.



Revealing mistakes

When driving to the bachelorette party, the car Kat and Nick are driving is on the left side of the road. In the next shot, it is still on the left side of the road, but the car's license plate is backwards.



Audio/visual unsynchronized

When Edward is chasing Jeffrey out of the church, they are heard shouting things at each other throughout the scene, yet the actors are clearly not speaking but are simply running around.



Errors in geography

When they stop at a pub in London to change Kat's dress, an American-style walk/don't walk sign is visible in shot.

When Kat is checking in to catch the flight from New York to London, an Easy Jet staff member is visible in his distinctive orange uniform. Easy Jet does not fly to or from any American airport.