Starting Tuesday, travelers who fail to follow the new policy could be denied the option to check their bags or be forced to miss their flight.

United Airlines will require all domestic passengers to check in for their flight at least 45 minutes before departure. The change from 30 minutes, which impacts those traveling without checked luggage, takes effect on June 3. To continue reading, log in or subscribe.

United Airlines is making a change to its check-in time policy. United customers must check in for a domestic flight at least 45 minutes before a flight without any checked bags starting June 3. The prior policy required travelers to check in at least a half hour before a flight.