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Flight Reliability

WN 1635 · Southwest Airlines

This number covered several routes in this period.

One number, several routes.

Airlines reuse flight numbers, and WN 1635 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

81%
Arrive within 15 minutes
7 min
Average arrival delay
0.6%
Cancelled
5 min early
Median arrival delay

Based on 353 historical flights. Data through May 2026.

The breakdown

On-time by weekday
  • Mon83%(58 flights)
  • Tue85%(47 flights)
  • Wed93%(45 flights)
  • Thu76%(53 flights)
  • Fri76%(54 flights)
  • Sat95%(43 flights)
  • Sun62%(50 flights)
On-time by departure window
  • 3–6 AM100%(20 flights)
  • 6–9 AM94%(131 flights)
  • 9 AM–12 PM100%(18 flights)
  • 12–3 PM—(9 flights)
  • 3–6 PM75%(110 flights)
  • 6–9 PM52%(62 flights)
On-time trend by month
71%
May

Jun 48% → May 71% on time

On-time arrival percentage by month
MonthOn-time percentageFlights
June 202548%21
July 202538%16
August 202597%29
September 202593%30
October 202590%31
November 2025100%21
December 202595%38
January 202691%33
February 202680%25
March 202669%42
April 202676%33
May 202671%31
Departures on time
80%
Diverted
0.3%
Flights flown
350
Months covered
12

Keep nerding

Based on 353 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.