United has adjusted its rewards policy for loyalty members. Now, its MileagePlus reward miles—which travelers can redeem on flights, experiences, hotels and other options—have no expiration date. "Giving customers a lifetime to use miles is an exceptionally meaningful benefit," said Luc Bondar, VP of loyalty and president of MileagePlus at United. Delta removed the expiration date for SkyMiles in 2011, and each passenger's American Airlines AAdvantage miles expire 18 months after he or she last earned or redeemed miles.