Another day, another airline rule change.
Starting June 3, United Airlines will require domestic travelers to check in at least 45 minutes before departure — syncing the carrier up with Delta and American, who have already done the same.
Those who flout the new flying law run the risk of having their trip plans run aground.
“The change brings greater consistency for our customers by aligning with our current checked baggage deadline and the check-in policies followed by most other airlines,” a United Airlines spokesperson told Yahoo News in a statement.
United’s check-in cutoff time used to be 30 minutes prior to departure, so those who like to wait until the last minute will find themselves with 15 minutes less leeway time.
The rule applies to domestic passengers — both with and without checked luggage.
International travelers are required to check in at least 60 minutes before departure, a common policy in the industry.
Aside from the check-in cutoff, most of the process is staying the same.

Passengers can check in for their flights up to 24 hours in advance online, on the United app or at an airport kiosk.
If travelers don’t meet the check-in time limit, United employees will “do our best to find another option,” the airline’s website notes.
However, the airline also says that employees have the right to deny service, which could lead to canceled flight reservations, denied boarding or denied options to check luggage.
It’s standard recommendation for travelers to arrive at least two hours before a domestic flight, but the policy change comes amid the popularity of the “check-in chicken” and “airport theory” trends.
With check-in chicken, travelers will intentionally delay their online check-in to the last minute in hopes of a better seat. The method relies on the fact that airlines will often charge extra for better seats, split up groups and initially assign fewer desirable seats.
When check-in closes, the leftover seats tend to be the more coveted ones, including those with extra legroom.
Just like in the game of chicken, the point is to push your luck to the limit and eventually get the desired outcome and your opponent folds. In this case, your opponent is the airline — and your desired outcome is a comfortable seat.
Meanwhile, the “airport theory” trend has people arriving at the airport just 15 minutes in advance to clear security, hoping to get to the gate without having to get up as early — or waste time lounging about the airport.