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Flight Reliability

WN 577 · Southwest Airlines

This number covered several routes in this period.

One number, several routes.

Airlines reuse flight numbers, and WN 577 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

69%
Arrive within 15 minutes
11 min
Average arrival delay
0.3%
Cancelled
1 min
Median arrival delay

Based on 308 historical flights. Data through May 2026.

The breakdown

On-time by weekday
  • Mon75%(52 flights)
  • Tue78%(32 flights)
  • Wed65%(31 flights)
  • Thu69%(54 flights)
  • Fri69%(54 flights)
  • Sat70%(33 flights)
  • Sun62%(50 flights)
On-time by departure window
  • 6–9 AM87%(62 flights)
  • 9 AM–12 PM100%(21 flights)
  • 12–3 PM71%(76 flights)
  • 3–6 PM58%(31 flights)
  • 6–9 PM56%(116 flights)
On-time trend by month
56%
May

Jun 33% → May 56% on time

On-time arrival percentage by month
MonthOn-time percentageFlights
June 202533%30
July 202532%31
August 202582%28
September 202573%26
October 202570%27
November 202591%32
December 202584%31
January 2026100%10
February 202680%15
March 202676%37
April 202676%21
May 202656%18
Departures on time
68%
Diverted
0.3%
Flights flown
306
Months covered
12

Keep nerding

Based on 308 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.