FlyerIntel Research
Airline Size and On-Time at the Same Airport
Across 61 airports, the carrier with the most departures arrived on time more often than the others at 26.
Published October 18, 2026 · Source period July 2023 – July 2026
Summary
26 of 61 airports had their busiest carrier arriving on time more often than the other carriers together, and the median airport shows a modest link between a carrier’s departures and its on-time rate (rank correlation 0.34).
Key findings
- At 26 of 61 airports the carrier with the most departures had a higher on-time arrival rate than all the others there combined; at 35 it did not.
- The median airport’s rank correlation between a carrier’s departures and its on-time rate is 0.34; it is 0.20 or higher at 42 airports, -0.20 or lower at 7, and between at 12.
- MEM shows the biggest carrier furthest ahead: Delta Air Lines at 88.1% against 79.6% for the rest, 8.5 points.
- DFW shows it furthest behind: American Airlines at 68.1% against 78.8% for the rest, 10.7 points.
- The median difference between the biggest carrier and the rest is -0.7 points.
Biggest carrier against the rest
At each of 61 airports with at least 5 carriers above 500 departures, the carrier with the most departures was set against the other carriers there, pooled. The biggest carrier was ahead at 26 airports and behind at 35. The gap is wider than 2 standard errors in the biggest carrier’s favor at 21 airports and against it at 32. Ranking all of an airport’s carriers instead, a carrier’s departures and its on-time rate move together at 42 airports (rank correlation 0.20 or higher), in opposite directions at 7, and with no clear pattern at 12.
The busiest airports in the comparison
| # | Airport | City | Carrier with the most departures | Its departures | Its share | On time, that carrier | On time, all others | Difference, points | Carriers compared | Rank correlation |
|---|---|---|---|---|---|---|---|---|---|---|
| 1 | ATL | Atlanta | Delta Air Lines | 717,729 | 70.9% | 79.9% | 76.0% | +3.9 | 13 | 0.23 |
| 2 | DEN | Denver | United Airlines | 320,379 | 33.3% | 78.0% | 75.0% | +2.9 | 11 | 0.57 |
| 3 | DFW | Dallas–Fort Worth | American Airlines | 510,667 | 53.1% | 68.1% | 78.8% | -10.7 | 10 | 0.33 |
| 4 | ORD | Chicago | United Airlines | 288,979 | 30.3% | 76.7% | 73.6% | +3.1 | 12 | 0.33 |
| 5 | CLT | Charlotte | American Airlines | 370,231 | 59.9% | 73.1% | 77.4% | -4.3 | 12 | 0.07 |
| 6 | PHX | Phoenix | Southwest Airlines | 205,927 | 34.4% | 77.5% | 81.8% | -4.2 | 12 | 0.34 |
| 7 | LAX | Los Angeles | SkyWest Airlines | 120,890 | 20.3% | 85.3% | 80.4% | +4.9 | 11 | 0.73 |
| 8 | LAS | Las Vegas | Southwest Airlines | 268,444 | 47.1% | 75.6% | 80.1% | -4.4 | 11 | 0.64 |
| 9 | SEA | Seattle | Alaska Airlines | 240,691 | 47.2% | 76.2% | 81.7% | -5.6 | 11 | 0.27 |
| 10 | MCO | Orlando | Southwest Airlines | 144,368 | 29.0% | 74.4% | 74.9% | -0.5 | 10 | 0.10 |
Airports are ordered by the departures of the carriers compared. On-time arrival is flights that left the airport and landed within 15 minutes, over flights that completed, for the same carrier and airport. Rank correlation is Spearman, across the carriers compared at that airport, of departures against on-time rate. 3 airports with fewer than 5 carriers above the floor are left out.
Airports where the biggest carrier is furthest ahead
| # | Airport | City | Carrier with the most departures | Its departures | Its share | On time, that carrier | On time, all others | Difference, points |
|---|---|---|---|---|---|---|---|---|
| 1 | MEM | Memphis | Delta Air Lines | 13,817 | 19.0% | 88.1% | 79.6% | +8.5 |
| 2 | CLE | Cleveland | United Airlines | 27,228 | 21.5% | 86.3% | 79.4% | +6.9 |
| 3 | RDU | Raleigh–Durham | Delta Air Lines | 35,574 | 19.8% | 84.7% | 78.1% | +6.6 |
| 4 | PIT | Pittsburgh | Republic Airways | 32,608 | 24.5% | 86.9% | 80.5% | +6.4 |
| 5 | SFO | San Francisco | United Airlines | 170,135 | 39.0% | 81.8% | 76.8% | +5.0 |
| 6 | LAX | Los Angeles | SkyWest Airlines | 120,890 | 20.3% | 85.3% | 80.4% | +4.9 |
| 7 | BUR | Burbank | Southwest Airlines | 57,496 | 61.8% | 84.5% | 80.0% | +4.5 |
| 8 | IND | Indianapolis | Republic Airways | 40,456 | 27.5% | 85.1% | 80.6% | +4.5 |
| 9 | ATL | Atlanta | Delta Air Lines | 717,729 | 70.9% | 79.9% | 76.0% | +3.9 |
| 10 | ORD | Chicago | United Airlines | 288,979 | 30.3% | 76.7% | 73.6% | +3.1 |
Difference is the biggest carrier’s on-time rate less the pooled rate of the other carriers compared at the airport, in points.
Airports where the biggest carrier is furthest behind
| # | Airport | City | Carrier with the most departures | Its departures | Its share | On time, that carrier | On time, all others | Difference, points |
|---|---|---|---|---|---|---|---|---|
| 1 | DFW | Dallas–Fort Worth | American Airlines | 510,667 | 53.1% | 68.1% | 78.8% | -10.7 |
| 2 | JFK | New York | JetBlue | 112,463 | 32.0% | 70.4% | 80.1% | -9.8 |
| 3 | DCA | Washington | PSA Airlines | 120,762 | 27.8% | 71.5% | 78.4% | -6.9 |
| 4 | BOS | Boston | JetBlue | 123,403 | 28.0% | 72.8% | 78.9% | -6.2 |
| 5 | SEA | Seattle | Alaska Airlines | 240,691 | 47.2% | 76.2% | 81.7% | -5.6 |
| 6 | FLL | Fort Lauderdale | Spirit Airlines | 67,556 | 24.2% | 68.8% | 73.8% | -5.0 |
| 7 | MIA | Miami | American Airlines | 189,097 | 55.5% | 71.0% | 75.9% | -4.9 |
| 8 | OAK | Oakland | Southwest Airlines | 100,569 | 85.8% | 81.4% | 85.9% | -4.5 |
| 9 | LAS | Las Vegas | Southwest Airlines | 268,444 | 47.1% | 75.6% | 80.1% | -4.4 |
| 10 | SJC | San Jose | Southwest Airlines | 87,775 | 59.8% | 82.5% | 86.8% | -4.3 |
Same measure, the largest negative differences.
What this does not show
Size is scheduled departures, and the carriers at one airport fly different routes: a carrier’s on-time rate is measured where its flights land, so it reflects the cities it serves as well as the airport it leaves. Regional carriers operate many short flights for a mainline brand and are counted as the operating carrier, which puts several of them low on size at hubs. The 645 carrier rows come from 61 airports, so a carrier appears once for each airport it qualifies at, and the airports are not independent of one another. Cancelled and diverted flights are not in the on-time rate, so a carrier that cancelled more can look better here than it was. This report does not say that being bigger makes a carrier more punctual, or the reverse.
Pages for what this report covers
Airports: Atlanta (ATL) · Denver (DEN) · Dallas–Fort Worth (DFW) · Chicago (ORD) · Charlotte (CLT) · Phoenix (PHX) · Los Angeles (LAX) · Las Vegas (LAS) · Seattle (SEA) · Orlando (MCO)
Airlines: Delta Air Lines · American Airlines · United Airlines · Southwest Airlines · SkyWest Airlines · Alaska Airlines
Methodology
Calculated by FlyerIntel from 21,708,321 individual flight records in the US Department of Transportation Bureau of Transportation Statistics Reporting Carrier On-Time Performance dataset, covering July 2023 through July 2026. Following BTS methodology, a flight counts as delayed when it arrives 15 or more minutes after its scheduled arrival time. Cancelled and diverted flights have no arrival time and are excluded from on-time rates rather than counted as late; cancellation rates are reported separately. Full definitions are published at /methodology/. Each figure is read from the departure rows of the airline-at-airport aggregate for covered airports, using carriers with at least 500 scheduled departures at the airport. On-time arrival is arrivals within 15 minutes over completed flights on that row. The biggest carrier is the one with the most scheduled departures; the others are pooled by adding their on-time and completed counts. A difference is called wide only when a two-proportion z of at least 2 separates the two rates; this guards against naming a tie and is not an interval.
Limitations
The source dataset covers scheduled domestic flights operated by carriers above the DOT reporting threshold; smaller carriers and international flights are not included. Flights sold under a mainline brand but flown by a regional carrier are attributed to the operating carrier, which is how the DOT records them. Past performance describes what has happened and is not a prediction about any individual flight.
Sources
- FlyerIntel analysis — FlyerIntel · source
- Reporting Carrier On-Time Performance — US Department of Transportation, Bureau of Transportation Statistics · source
Full FlyerIntel methodology · Report a problem with this analysis