Frontier Airlines is also making major upgrades including UpFront Plus seating, which offers extra legroom and a guaranteed empty middle seat. Soon, top customers will enjoy unlimited free companion travel, and by late 2025, First Class seating will be available on all flights, keeping comfort high and prices low.

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.