Exhibit 15

October 12, 2023

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-3 No.’s 333-272728 and 333-262678 and Form S-8 No.’s 333-142424, 333-149308, 333-154818, 333-151060 and 333-212525) of Delta Air Lines, Inc. for the registration of its securities of our report dated October 12, 2023 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, 2023.

/s/ Ernst & Young LLP