WN851 HOU → MDW

Southwest Airlines · Houston, TX to Chicago, IL · 64 flights observed, 2025-11-02 to 2026-01-05 · 937 mi

This flight's reliability varies a lot by day of week — 100% on-time on Thursdays vs. 60% on Sundays.

WN851 covers more than one route in the data window — the stats below are for HOU → MDW, the one it has flown most recently. The others are linked under “Other routes”.

On-time arrival
84%
Median delay
+2 min
90th percentile
+21 min
Cancellation rate
2%

How often is WN851 on time?

Across 64 flights on HOU → MDW from 2025-11-02 to 2026-01-05, WN851 arrived within 15 minutes of schedule 84% of the time. The median arrival delay was +2 min, and the worst 10% of flights arrived +21 min or later. 2% of flights were cancelled.

Delay distribution

Arrival delay for completed flights (excludes cancellations and diversions).

ArrivalFlightsShare
Early / on-time5384%
16-30 min58%
31-60 min58%
61-120 min00%
2+ hrs00%

Performance by month

MonthFlightsOn-timeAvg delay
2025-112781%+2 min
2025-123184%+8 min
2026-015100%+1 min

Performance by day of week

DayFlightsOn-time
Mon989%
Tue978%
Wed989%
Thu8100%
Fri989%
Sat989%
Sun1060%

Based on US Department of Transportation Bureau of Transportation Statistics on-time data. Loading live conditions and full charts…