Delta Air Lines (DAL) competes with United Airlines Holdings, Southwest Airlines, and American Airlines Group for domestic and international airline travel business in the United States.

In 2026, United Airlines is the most direct and functional comparison to Delta Air Lines, as both operate as premium-focused, legacy global carriers with massive international networks. Like Delta, United has invested heavily in its "United Next" strategy, retrofitting its fleet with seatback entertainment, high-speed Wi-Fi, and larger overhead bins to match Delta’s industry-leading domestic product. In terms of alliance and global reach, United’s "Star Alliance" provides a similar level of elite reciprocity as Delta’s "SkyTeam." Outside of the U.S., Lufthansa is often cited as a comparable international peer due to its focus on operational reliability and premium cabin consistency. For travelers who value Delta’s specific "service culture," Alaska Airlines is a frequent comparison in the domestic market, although it lacks Delta's wide-body international footprint. Both Delta and United now utilize dynamic pricing for their loyalty programs (SkyMiles and MileagePlus), meaning the "value" of their points is roughly similar, though Delta is often perceived to have a slight edge in operational reliability and "soft" service touches from its cabin crew.