It's all about being able to get to and from destinations on time, the airline says.
"Our tests indicate that this new boarding process will improve our dependability and on-time performance, while being easier and more enjoyable for our customers," Carol Wright, the airline's vice president of customer planning, said in a statement.
The airline said tests earlier this year at airport gates in Austin, Texas; Baltimore; Denver; Fort Lauderdale, Fla.; Kansas City, Mo.; Minneapolis-St. Paul; and Washington, D.C., showed the process proved to be quicker, and customers liked it too.
But traveling light doesn't mean you go straight to the head of the line.
On boarding domestic flights, American gives preference to first-class passengers and members of the military in uniform, then business class, then frequent fliers enrolled in the airline's loyalty program and then customers without overhead luggage.