Starting on Wednesday, the Dallas-based carrier will charge customers $35 for their first checked bag and $45 for their second checked bag. The bag fee change will also apply to existing flight itineraries changed on or after May 28, Southwest confirmed to "Good Morning America."

Southwest passengers will notice many changes at their favorite airline, from baggage fees to flight credits to Rapid Rewards to assigned seats.

It’s the last day to book a flight on Southwest Airlines without being hit with a fee to check bags after the airline abandoned a decades-long luggage policy that executives once described as key to differentiating the budget carrier from its rivals.