After more than 50 years, Southwest Airlines’ “bags fly free” policy is finally coming to an end. 

Southwest on Tuesday announced the first checked bag will cost $35, while a second checked bag will cost $45. The policy will begin tomorrow, when some passengers may be subject to a checked bag fee when booking a flight on the discount carrier. 

The new policy only applies to flights booked on May 28 or later, which means today is the last day to book if passengers want to avoid the new fee. 

There are, however, some carve-outs to the new policy: Business Select/Choice Extra and A-List Preferred customers will receive two free checked bags, while A-List and Chase Rapid Reward credit card members will get one free checked bag.

Southwest announced the end of its free bag check policy in March amid mounting pressure to improve its financial performance. The airline also said last year that it would start selling assigned seats, a major departure from its longstanding open seating policy.