Southwest Airlines suffered the steepest year-over-year drop in punctuality among North American airlines in September, according to Cirium's monthly on-time performance rankings. The carrier's on-time arrival rate fell to 71.14%, down from 81.46% in September 2025, a decline of 10.32 percentage points. Every U.S. airline in the rankings was less punctual and cancelled a larger share of flights than a year earlier, View from the Wing reported in its analysis of the data.
WestJet leads, Delta tops the U.S. carriers
Cirium's September 2026 report puts WestJet first in North America with 85.31% of flights arriving on time, followed by Delta at 82.52% and Alaska Airlines at 80.73%. Cirium counts an arrival as on time when the aircraft reaches the gate within 15 minutes of schedule; cancelled flights are not counted as late arrivals.
- WestJet: 85.31% on time (84.49% in September 2025), 0.74% cancelled
- Delta: 82.52% (87.50%), 0.92% cancelled
- Alaska: 80.73% (84.59%), 1.57% cancelled
- United: 78.65% (84.16%), 0.89% cancelled
- American: 77.11% (82.10%), 1.01% cancelled
- Frontier: 75.49% (79.82%), 0.65% cancelled
- JetBlue: 74.64% (79.81%), 1.80% cancelled
- Air Canada: 73.19% (81.07%), 3.31% cancelled
- Southwest: 71.14% (81.46%), 0.38% cancelled
There was some good news in the numbers. All nine airlines improved their on-time performance compared with August.
Southwest: last for punctuality, first for completing flights
Southwest actually improved month on month, from 68.28% in August to 71.14% in September. But Frontier, JetBlue and Air Canada improved faster, pushing Southwest from sixth place to ninth. At the same time, Southwest remained the airline least likely to cancel. Its completion factor of 99.62% means it cancelled just 0.38% of flights, about one in 263 and less than half the rate at United, Delta or American.
The airline has been working to get more flying out of each Boeing 737 by cutting time on the ground and adding red-eye flights. That lowers aircraft and labour costs when the schedule runs smoothly, but leaves less slack to absorb problems. View from the Wing also points to slower boarding as more passengers bring carry-on bags into the cabin since Southwest ended its free checked bags policy. On the airline's July earnings call, chief operating officer Andrew Watterson acknowledged that full flights were taking longer to turn, particularly in the final 10 minutes before departure.
Delta recovers, American still trails
Delta's September was a clear improvement on a difficult summer. Its cancellation rate fell from 1.77% in August to 0.92%, and on-time arrivals rose from 79.15% to 82.52%. The airline had previously cited pilot availability, crew scheduling and maintenance recovery as problems. Delta finished 3.87 points ahead of United on punctuality, though United cancelled slightly fewer flights.
American also improved, cutting cancellations from 2.28% in August to 1.01% and lifting on-time arrivals to 77.11%. But its gap to Delta was 5.41 points, almost exactly the 5.40-point gap of a year earlier, despite American's work on more realistic block times and a plan to spread Dallas-Fort Worth flying across 13 connecting banks instead of nine.
Two Delta hubs among the best airports
In Cirium's airport rankings, which measure departures, only two U.S. airports made the top 20 among large airports: Salt Lake City in 13th place with 85.56% of departures on time and Minneapolis-St. Paul in 16th at 85.13%. Both are Delta hubs. Harbin in China led the large-airport category at 96.74%.
Comments
Loading commentsβ¦