Southwest sets its first checked bag fee, starting at $35

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.