Check the carry-on policies of these big U.S. airlines before flying to avoid unnecessary stress at the airport.

Airline carry-on rules aren’t what they used to be. Here’s how policies differ and why overhead bin tension is rising.

This article is a part of CNN Underscored’s Summer Travel Week, a weeklong focus on how to travel smarter and save money during one of the busiest travel seasons of the year. You have a handful of ...