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Flight Reliability

WN 1240 · Southwest Airlines

This number covered several routes in this period.

One number, several routes.

Airlines reuse flight numbers, and WN 1240 moved between routes during this period. Numbers below combine all of them, so treat them as background, not a verdict. For a cleaner answer, check the route you are actually flying.

Combined across all its routes

83%
Arrive within 15 minutes
3 min
Average arrival delay
0.9%
Cancelled
5 min early
Median arrival delay

Based on 326 historical flights. Data through May 2026.

The breakdown

On-time by weekday
  • Mon76%(46 flights)
  • Tue75%(44 flights)
  • Wed86%(42 flights)
  • Thu84%(45 flights)
  • Fri83%(46 flights)
  • Sat86%(49 flights)
  • Sun90%(50 flights)
On-time by departure window
  • 3–6 AM93%(58 flights)
  • 6–9 AM97%(36 flights)
  • 9 AM–12 PM97%(32 flights)
  • 12–3 PM82%(89 flights)
  • 3–6 PM71%(83 flights)
  • 6–9 PM63%(24 flights)
On-time trend by month
91%
May

Jun 100% → May 91% on time

On-time arrival percentage by month
MonthOn-time percentageFlights
June 2025100%31
July 202574%31
August 2025100%11
October 202580%30
November 202587%30
December 202593%30
January 202688%16
February 202680%40
March 202648%27
April 202682%34
May 202691%34
Departures on time
80%
Diverted
0.3%
Flights flown
322
Months covered
12

Keep nerding

Based on 326 historical flights, because apparently we checked. Historical flight data: U.S. Bureau of Transportation Statistics, June 2025 – May 2026. Data through May 2026. How we calculate this.