Delta Air Lines (DAL) 10-Q 2013 Q3 Quarterly report

Exhibit 15

October 23, 2013

To the Board of Directors and Stockholders of

Delta Air Lines, Inc.

We are aware of the incorporation by reference in the Registration Statements (Form S-8 No.’s 333-142424, 333-149308, 333-154818 and 333-151060) of Delta Air Lines, Inc. for the registration of shares of its common stock of our report dated October 23, 2013 relating to the unaudited condensed consolidated interim financial statements of Delta Air Lines, Inc. that are included in its Form 10-Q for the quarter ended September 30, 2013.

/s/ Ernst & Young LLP