Die Hard was the first one I thought of.
Technically, most of Two Seconds takes place in two seconds (with a couple of minutes before and after). It’s done in flashbacks, but those are supposed to occur in the two seconds before the man dies in the electric chair.
Rope (1948) – A dinner party hosted by murderers.
The Set-Up (1949) – Boxing tale takes place over a little more than an hour, same as the film’s running time.
Cleo from 5 to 7 (1961) – Woman awaits potential life-altering medical diagnosis.
Dr. Strangelove (1963)
The Taking of Pelham, One, Two, Three (1974, 2009)
Don’s Party (1976) – Election party in Australia.
Salome’s Last Dance (1988) – An evening at the brothel with Oscar the Wilde and Bosie.
Falling Down (1993) – Michael Douglas flips out.
The Ice Harvest (2005) – Criminal behavior on Christmas Eve and Christmas Day.
Attack the Block (2011) – Gang defends their ‘hood against aliens.
Locke (2014) – Dude drives his BMW.
How about The Wannsee Conference, and it’s more recent counterpart Conspiracy? And IMHO both were outstanding movies.
The longest movie that I’ve seen which is one continuous shot is the 2015 German film Victoria directed by Sebastian Schipper, which is 140 minutes long. This Wikipedia entry lists three longer ones and many that are shorter. Two of the ones they list (Timecode and Russian Ark) are reasonably well known:
[nitpick] It’s just Neighbors, no article. Fantastic movie.
Y’all have excellent taste in movies. 
My contribution is 16 Blocks.
Agree with this. It was poorly received, but it was one of the better adaptations of book-to-movie. I loved the book (I was on a Thomas Berger kick for awhile) and this was a good job. Also, if you read the book, it’s clear that Ackroyd was perfectly cast as Captain Vic.
I haven’t actually watched it, but I believe The Purge takes place over a 12 hour period.
Another nitpick: Aykroyd
(I learned that here on the Dope)
Let it Ride is a 1989 comedy starring Richard Dreyfuss. Except for about two minutes the night before, the whole thing takes place at a racetrack in an afternoon.
Groundhog Day
Adventures In Babysitting
Clue
The Ref
3 O’clock High which is an underrated 80’s movie.
Some films that take place around a holiday are sure to qualify - stuff like Pieces of April or The Ice Storm happen on Thanksgiving or start just before. Some Christmas movies, too, no doubt.
Oh, and Death At A Funeral is all one day.
Good point
Arthur Christmas takes place overnight.
Same for A Christmas Carol
After the Thin Man
Since it’s mostly a flashback, The Miracle of Morgan’s Creek takes place in only a few minutes of real time.
It’s more a collection of 5 shorts, but Night on Earth certainly qualifies. Good film also.
Margin Call, one of the better films about Wall Street, takes place over a single evening.
Duel takes place over one day, if that counts as “a few” hours. During the opening credits Mann is shown leaving his house for his business trip in the morning. As the closing credits roll, he’s sitting on the edge of the canyon as the sun starts to set. Although when he first encountered the truck at the beginning of the movie he’d probably already been driving for a while, so you could argue that most of the actual action takes place over a few hours.