About 1 in 3 WN 40 flights from Houston arrived 15+ minutes late, diverted or cancelled over the past year (31%); 0.5% were cancelled. The typical flight landed 3 minutes early.
WN 40: HOU → DAL
Scheduled to leave Houston at 4:00 p.m. local time. Over the past year it arrived on time 69% of the time (198 flights), worse than other WN flights on the route at that hour (74%). Last seen in the data Aug 31, 2026.
Month by month
By day of week
| Day | Flights | On time |
|---|---|---|
| Monday | 46 | 70% |
| Tuesday | 13 | — |
| Wednesday | 10 | — |
| Thursday | 43 | 67% |
| Friday | 47 | 77% |
| Saturday | 14 | — |
| Sunday | 25 | 56% |
Why it was late
All flights HOU → DAL · Connecting off WN 40? Check the risk
Questions
How often is WN 40 from HOU to DAL late?
Southwest Airlines 40 from Houston, TX to Dallas, TX arrived 15 or more minutes late, was diverted or was cancelled on 31% of 198 scheduled flights between September 2025 and August 2026. 0.5% were cancelled.
Flight numbers change. Figures cover flights with this airline, number and route only. "Likely range" is the 95% interval for the true on-time rate given the number of flights. This is history, not live status: check Southwest Airlines for today's flight. Method.