Dallas (DAL) to Seattle (SEA): On-Time Performance
Data through May 2026
Dallas (DAL) to Seattle (SEA) is a thinner route than most in this dataset — 216 departures over the past year, roughly 4 a week — so treat these numbers as indicative rather than definitive. Of the flights that did operate, 72% arrived on time, noticeably below the national average of 78%.
- On-time
- 72%
- arrived <15 min late
- Avg delay
- 14 min
- completed flights
- Cancelled
- 0.7%
- Flights/day
- 0.59
- last 12 months
- Duration
- 4h 17m
- scheduled
- Distance
- 1,670 mi
Best airline from DAL to SEA
2 airlines flew this route regularly between 2024-06 and 2026-05.
| Airline | On-time | Avg delay | Cancelled | Flights |
|---|---|---|---|---|
| Alaska Airlinesmost reliable | 77% | 10 min | 0.6% | 312 |
| Southwest Airlines | 65% | 18 min | 0.8% | 259 |
Monthly on-time trend
Best time to fly from DAL to SEA
Aim for departures around 2 p.m. (79% on-time); avoid 6 p.m. departures (55%).
By day of week
| Day | On-time | Avg delay |
|---|---|---|
| Monday | 80% | 8 min |
| Tuesdaybest | 83% | 7 min |
| Wednesday | 76% | 14 min |
| Thursday | 73% | 13 min |
| Friday | 67% | 19 min |
| Saturday | 67% | 18 min |
| Sunday | 63% | 17 min |
What causes delays on this route
Share of total delay minutes by cause, as reported by carriers to the US DOT.
- Late-arriving aircraft43%
- Airline operations25%
- National airspace system26%
- Weather5%
Frequently asked questions
- How often are flights from DAL to SEA delayed?
- 28% of DAL–SEA flights arrived 15 or more minutes late (the US DOT definition of a delay) between 2024-06 and 2026-05. The average arrival delay across completed flights was 14 minutes.
- Which airline is most reliable from DAL to SEA?
- Alaska Airlines has the best on-time record on this route at 77%, based on 312 flights. 2 airlines flew DAL–SEA frequently enough to compare in this period.
- What is the best time of day to fly from DAL to SEA?
- Departures around 2 p.m. have the best record (79% on-time), while departures around 6 p.m. have the worst (55%). As on most US routes, delays accumulate through the day, so earlier flights are generally safer.
- How long is the flight from DAL to SEA?
- The scheduled DAL–SEA flight time averages 4h 17m over 1,670 miles. Actual arrival times vary — flights on this route land 15+ minutes late 28% of the time.
- How often are DAL to SEA flights cancelled?
- 0.7% of scheduled flights on this route were cancelled between 2024-06 and 2026-05, at or below the national rate of 1.6%.
- What is the worst month to fly from DAL to SEA?
- August 2024 was the roughest month in this dataset, with only 59% of arrivals on time. The best was October 2024 at 90%. If your dates are flexible, that 32-point gap is worth planning around.
Explore related pages
More routes from DAL
Based on 571 flights, 2024-06–2026-05. Source: US DOT Bureau of Transportation Statistics. Updated 2026-07-01.