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Flight Reliability

WN 3728 · Southwest Airlines

This number covered several routes in this period.

One number, several routes.

Airlines reuse flight numbers, and WN 3728 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

71%
Arrive within 15 minutes
14 min
Average arrival delay
1.8%
Cancelled
0 min
Median arrival delay

Based on 336 historical flights. Data through May 2026.

The breakdown

On-time by weekday
  • Mon64%(42 flights)
  • Tue80%(49 flights)
  • Wed80%(49 flights)
  • Thu60%(42 flights)
  • Fri72%(43 flights)
  • Sat79%(53 flights)
  • Sun63%(51 flights)
On-time by departure window
  • 6–9 AM91%(56 flights)
  • 9 AM–12 PM82%(55 flights)
  • 12–3 PM83%(77 flights)
  • 3–6 PM57%(28 flights)
  • 6–9 PM47%(98 flights)
  • 9 PM–12 AM87%(15 flights)
On-time trend by month
89%
May

Jun 52% → May 89% on time

On-time arrival percentage by month
MonthOn-time percentageFlights
June 202552%29
July 202543%30
August 202558%45
September 202553%47
October 202578%32
January 202689%26
February 202693%27
March 202688%16
April 202693%30
May 202689%36
Departures on time
67%
Diverted
0.3%
Flights flown
329
Months covered
12

Keep nerding

Based on 336 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.