As of February 2015, passengers on Delta Airlines can carry one bag plus one personal item onto the plane; they can check-in an unlimited number of bags, but fees may apply. Carry-on bags must be less than 45 inches in length, height and width combined.
Delta charges a baggage fee for most flights; cost varies depending on flight and seat class. For example, passengers flying Economy class within the U.S. on Delta pay $23 online for their first checked bag and $32 for the second bag as of February 2015. Any additional bags are charged an Excess Baggage Fee of $125 each. Delta passengers should check with the airline to find updated polices on bags for their flight.