Southwest Airlines will begin charging customers a fee to check bags. It's a significant change for the budget carrier, which built years of advertising campaigns around its policy of letting passengers check up to two bags for free.

Southwest Airlines Co. will begin charging passengers for some checked luggage, ending a free-bag policy that has been a hallmark of the carrier since its founding more than five decades ago.

Southwest will start charging passengers for checked luggage and sell basic economy tickets, as the maverick airline becomes more like its rivals.