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Flight Reliability

WN 1840 · Southwest Airlines

This number covered several routes in this period.

One number, several routes.

Airlines reuse flight numbers, and WN 1840 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

78%
Arrive within 15 minutes
8 min
Average arrival delay
0.5%
Cancelled
2 min early
Median arrival delay

Based on 396 historical flights. Data through May 2026.

The breakdown

On-time by weekday
  • Mon73%(64 flights)
  • Tue86%(42 flights)
  • Wed90%(41 flights)
  • Thu82%(66 flights)
  • Fri74%(73 flights)
  • Sat89%(46 flights)
  • Sun61%(61 flights)
On-time by departure window
  • 6–9 AM91%(57 flights)
  • 9 AM–12 PM75%(52 flights)
  • 12–3 PM77%(96 flights)
  • 3–6 PM69%(65 flights)
  • 6–9 PM82%(102 flights)
  • 9 PM–12 AM57%(21 flights)
On-time trend by month
78%
May

Jun 79% → May 78% on time

On-time arrival percentage by month
MonthOn-time percentageFlights
June 202579%29
July 202579%29
August 202588%33
September 202574%34
October 202589%28
November 202592%39
December 202571%31
January 202678%32
February 202669%42
March 202652%29
April 202684%31
May 202678%36
Departures on time
72%
Diverted
0.3%
Flights flown
393
Months covered
12

Keep nerding

Based on 396 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.