United Airlines will start requiring all passengers traveling within the U.S. to be checked in for their flights 45 minutes before departure.

Previously, the airline required passengers who weren't checking a bag to be checked in 30 minutes before takeoff.

Passengers traveling internationally are required to check in for their flights at least an hour in advance, according to United's website. There are also special time limits for certain airports in the U.S. that may require you to check in sooner.

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In a statement provided to multiple media outlets, United said the change "brings greater consistency" for its customers and meets the standard set by several other airlines.

Airlines like American and Delta have a 45-minute cutoff for domestic passengers checking baggage.

Most travel experts and airport officials will advise you to arrive at the airport at least two hours before your plane is scheduled to depart.

Typically, the window to check in for a flight opens 24 hours before your departure.