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Flight Reliability

WN 1921 · Southwest Airlines

This number covered several routes in this period.

One number, several routes.

Airlines reuse flight numbers, and WN 1921 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

74%
Arrive within 15 minutes
11 min
Average arrival delay
0.7%
Cancelled
2 min early
Median arrival delay

Based on 453 historical flights. Data through May 2026.

The breakdown

On-time by weekday
  • Mon77%(79 flights)
  • Tue88%(57 flights)
  • Wed85%(59 flights)
  • Thu65%(85 flights)
  • Fri58%(77 flights)
  • Sat89%(35 flights)
  • Sun69%(55 flights)
On-time by departure window
  • 6–9 AM92%(71 flights)
  • 9 AM–12 PM85%(135 flights)
  • 12–3 PM62%(87 flights)
  • 3–6 PM66%(103 flights)
  • 6–9 PM62%(37 flights)
  • 9 PM–12 AM36%(14 flights)
On-time trend by month
67%
May

Jun 68% → May 67% on time

On-time arrival percentage by month
MonthOn-time percentageFlights
June 202568%34
July 202546%28
August 202591%23
September 202586%22
October 202558%96
November 202585%27
December 202586%29
January 202694%46
February 202684%37
March 202673%30
April 202678%36
May 202667%39
Departures on time
71%
Diverted
0.7%
Flights flown
447
Months covered
12

Keep nerding

Based on 453 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.