Delta operates a larger fleet (900+ aircraft vs 800+) and maintains higher on-time performance (83.5% vs 81.2%), while United offers more international routes and aggressive expansion in emerging markets. Both are major US carriers with comparable safety records and frequent flyer programs.
Delta Air Lines vs United Airlines — Side-by-side comparison on A Versus B
Choose Delta if you prioritize reliability and on-time performance, with a preference for domestic connectivity and a more generous frequent flyer program. Choose United if you need extensive international coverage, prefer flying to emerging markets, and value aggressive route expansion and competitive business class amenities.
Compare Delta Air Lines vs United Airlines
Premium U.S. carrier known for operational efficiency and customer service excellence.
Major U.S. carrier with extensive international network and competitive pricing strategy.
SkyMiles/MileagePlus Miles Devaluation (2024)
Customer Satisfaction Score (2024 J.D. Power)
Delta Air Lines vs United Airlines — Comparison Data
Structured comparison data for Delta Air Lines vs United Airlines with 157 attributes.
Customer Satisfaction Score (J.D. Power 2025)
Premium Cabin Seat Pitch (Business/Polaris)
Average Domestic Round-Trip Ticket Price
Customer Satisfaction Score (J.D. Power 2024)
DOT Complaints Per 100,000 Passengers (2024)
J.D. Power Customer Satisfaction Score (2024)
Business Class Lie-Flat Seats (Long-Haul)
Delta Air Lines vs United Airlines — Attribute Category Vocabulary
Taxonomy of attribute categories used to classify comparison data for Delta Air Lines vs United Airlines.
Which airline has better on-time performance?
Delta Air Lines maintains the highest on-time performance at 83.5% (2024 data), compared to United's 81.2%. This 2.3 percentage point difference translates to Delta being more reliable for time-sensitive connections and meetings.
Yes, both Delta and United charge $35 for the first checked baggage on standard tickets. A second bag costs $45 at both carriers. However, elite frequent flyer members and certain fare classes receive free baggage at both airlines.
United Airlines serves 72 countries across 6 continents, compared to Delta's 68 countries. United has aggressively expanded in Asia-Pacific markets and offers more emerging market access, particularly beneficial for business travelers needing diverse international connections.
Delta's SkyMiles retains 95% of miles value annually (5% devaluation), while United's MileagePlus devalued by 8% in 2024. Delta also offers slightly better elite benefits with SkyClub access. However, United's MileagePlus miles are often easier to redeem on premium cabin seats.
Both Delta and United maintain exceptional safety records well above industry standards. The FAA rates both carriers as Category 1 (highest safety rating). Statistical safety differences between major US carriers are negligible; both operate under identical FAA regulations with similar accident rates.