Delta received several upgraded ratings and an "outlook positive" from Moody's Investors Service on Tuesday.
Moody's, one of the top bond credit ratings agencies, said it anticipates that Delta will be the industry's leader in free cash flow generation this year and next, producing about or above $3 billion annually, about 10 percent higher than United Airlines' in 2015 and more so in 2016.
Moody's Vice President - Senior Credit Officer, Jonathan Root, noted Delta's "long-running focus on reducing funded debt, effective capacity management and significantly lower fuel expenses."
"The consolidation in the U.S. airline industry that has occurred since 2007 has reduced industry risk," Root was quoted saying in a press release. "However, the similar strategy of pursuing acceptable returns on invested capital has been the bigger contributor to the improved creditworthiness of the US airlines, including Delta."
Moody's ranks the creditworthiness and overall fiscal health of companies that borrow money. Stronger ratings typically mean lower risk to investors and thus cheaper interest rates for the companies that borrow.