https://www.cntraveler.com/story/delayed-baggage-compensation-what-airlines-really-owe-you
Back in 2011, the U.S. Department of Transportation mandated that all domestic airlines must reimburse you for any “reasonable expenses” related to delayed luggage, up to $3,300, that became $3,400 in 2013. That doesn’t mean the airline owes you for the full value of whatever’s in your suitcase; it only owes you for anything you have to buy that you would not otherwise. For example, if you were traveling to race in a triathlon and your bag wasn’t to you by race day, you’d need to go out and buy all new swimming, biking, and running gear. Keep the receipts for all of it and the airlines must pay you back.
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Airlines have this information in their contracts of carriage, which most of us read about as often as the back of a tax form. Most airlines will offer you a “stipend” of around $50 a day for fun stuff like toothbrushes and underwear. And though that stipend can be applied against the $3,400, it’s not a limit on what you can spend.
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The Montreal Convention of 1999 mandates that passengers are entitled to a maximum of 1,131 Special Drawing Rights—or SDR—for any expenses incurred as a result of delayed baggage. SDR is a sort of combined currency based on U.S. dollars, euros, yen, pounds sterling, and the Chinese renminbi, and currently exchanges at about 0.7 per U.S. dollar. That means you’re entitled to around $1,600 maximum for a delayed bag.
