Skip to content
WanderNerd

Flight Reliability

WN 3857 · Southwest Airlines

This number covered several routes in this period.

One number, several routes.

Airlines reuse flight numbers, and WN 3857 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
9 min
Average arrival delay
0%
Cancelled
1 min early
Median arrival delay

Based on 217 historical flights. Data through May 2026.

The breakdown

On-time by weekday
  • Mon81%(32 flights)
  • Tue85%(27 flights)
  • Wed86%(28 flights)
  • Thu75%(32 flights)
  • Fri66%(32 flights)
  • Sat61%(23 flights)
  • Sun64%(39 flights)
On-time by departure window
  • 6–9 AM(5 flights)
  • 9 AM–12 PM97%(30 flights)
  • 12–3 PM75%(106 flights)
  • 3–6 PM62%(71 flights)
  • 6–9 PM(1 flights)
On-time trend by month
69%
May

Jun 66% → May 69% on time

On-time arrival percentage by month
MonthOn-time percentageFlights
June 202566%29
July 202568%28
October 202576%29
November 2025100%20
December 202575%20
March 202676%25
April 202674%27
May 202669%26
Departures on time
68%
Diverted
1.8%
Flights flown
213
Months covered
10

Based on 217 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.