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Flight Reliability

WN 4040 · Southwest Airlines

This number covered several routes in this period.

One number, several routes.

Airlines reuse flight numbers, and WN 4040 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

76%
Arrive within 15 minutes
9 min
Average arrival delay
0%
Cancelled
2 min early
Median arrival delay

Based on 178 historical flights. Data through May 2026.

The breakdown

On-time by weekday
  • Mon87%(23 flights)
  • Tue82%(22 flights)
  • Wed84%(19 flights)
  • Thu68%(22 flights)
  • Fri74%(23 flights)
  • Sat81%(32 flights)
  • Sun65%(37 flights)
On-time by departure window
  • 6–9 AM100%(28 flights)
  • 9 AM–12 PM—(2 flights)
  • 12–3 PM—(1 flights)
  • 3–6 PM80%(15 flights)
  • 6–9 PM80%(39 flights)
  • 9 PM–12 AM67%(93 flights)
On-time trend by month
100%
May

Jun 80% → May 100% on time

On-time arrival percentage by month
MonthOn-time percentageFlights
June 202580%30
July 202567%30
October 202579%33
December 202555%11
February 2026100%10
March 202676%29
April 202682%11
May 2026100%11
Departures on time
73%
Diverted
0%
Flights flown
178
Months covered
11

Keep nerding

Based on 178 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.