May 2026 · federal filings
How often each route actually runs late
Every large US airline files its arrival times with the Department of Transportation each month, including what caused each delay. These are the 59 busiest carrier-and-city-pair combinations, each with at least 300 flights in the window so the percentages mean something. The worst of them, LAX to SFO on United Airlines, ran late 52% of the time.
American Airlines
Airline guide- Dallas/Fort Worth – Phoenix25.7% late
- Dallas/Fort Worth – Los Angeles28.6% late
- Dallas/Fort Worth – Chicago32.5% late
- Dallas/Fort Worth – New York31.1% late
- Dallas/Fort Worth – Las Vegas29.8% late
- Dallas/Fort Worth – Miami26.9% late
- Charlotte – Orlando24.6% late
- Dallas/Fort Worth – Orlando31.5% late
- Austin – Dallas/Fort Worth33.6% late
- Charlotte – Dallas/Fort Worth20.2% late
- Washington – Miami23.5% late
- New York – Chicago26.1% late
- Dallas/Fort Worth – San Antonio36.5% late
- New York – Miami29.9% late
- Charlotte – Chicago23.7% late
- Washington – Dallas/Fort Worth19.3% late
Delta Air Lines
Airline guide- Atlanta – Orlando28.5% late
- Atlanta – New York24% late
- Atlanta – Tampa29.1% late
- Atlanta – Fort Lauderdale22.8% late
- Atlanta – Jacksonville24.1% late
- Atlanta – West Palm Beach/Palm Beach19.9% late
- Atlanta – Detroit29.7% late
- Atlanta – Los Angeles21.2% late
- Atlanta – Washington29.5% late
- Atlanta – Boston20.4% late
- Atlanta – Raleigh/Durham17.4% late
- Atlanta – Nashville20.6% late
- Atlanta – Memphis19.6% late
- Atlanta – Birmingham20.8% late
- New York – Los Angeles21.9% late
United Airlines
Airline guide- New York – Chicago28.1% late
- Newark – Chicago21.7% late
- Denver – Chicago20.8% late
- Chicago – San Francisco37.3% late
- Houston – Chicago21.8% late
- Newark – San Francisco29.5% late
- Denver – Houston17.8% late
- Newark – Orlando12.4% late
- Washington – Chicago29% late
- Denver – San Francisco40% late
- Newark – Los Angeles16.9% late
- Houston – San Francisco33.6% late
- Houston – Los Angeles15.8% late
- Los Angeles – Chicago19.2% late
- Los Angeles – San Francisco52% late
Southwest Airlines
Airline guideAlaska Airlines
Airline guideFigures cover May 2026, a single reporting month, from the US DOT Bureau of Transportation Statistics On-Time Performance database. Retrieved 2026-07-28. Reporting under 14 CFR part 234 covers domestic US scheduled service only, so no international route appears — including anything to or from Mexico.
Looking for a carrier overall rather than one route? The airline accountability index ranks every reporting carrier and shows how much of each one's delay minutes trace back to the airline itself.