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Flight Reliability

WN 3556 · Southwest Airlines

This number covered several routes in this period.

One number, several routes.

Airlines reuse flight numbers, and WN 3556 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
19 min
Average arrival delay
0.6%
Cancelled
1 min
Median arrival delay

Based on 343 historical flights. Data through May 2026.

The breakdown

On-time by weekday
  • Mon73%(44 flights)
  • Tue72%(57 flights)
  • Wed70%(57 flights)
  • Thu61%(43 flights)
  • Fri64%(44 flights)
  • Sat74%(39 flights)
  • Sun68%(57 flights)
On-time by departure window
  • 6–9 AM—(1 flights)
  • 9 AM–12 PM83%(35 flights)
  • 12–3 PM78%(74 flights)
  • 3–6 PM56%(84 flights)
  • 6–9 PM68%(147 flights)
On-time trend by month
75%
May

Jun 30% → May 75% on time

On-time arrival percentage by month
MonthOn-time percentageFlights
June 202530%30
July 202541%29
August 202569%45
September 202581%47
October 202581%32
November 202576%29
December 202561%31
January 202689%27
February 202658%24
March 202685%20
April 202693%15
May 202675%12
Departures on time
67%
Diverted
0%
Flights flown
341
Months covered
12

Keep nerding

Based on 343 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.