Southwest Airlines SEA to DEN on-time performance
Southwest Airlines nonstop flights from Seattle to Denver · Aug 2025 – Jul 2026
On-time arrivals
68%
arrived < 15 min late
Cancelled
0.6%
8 flights
Avg arrival delay
17 min
49 min when late
Rank on route
#6 of 6
route average 78% on time
Key facts
- Southwest Airlines flights on SEA to DEN arrived on time 68% of the time in Aug 2025 – Jul 2026.
- 0.6% were cancelled, and 7% arrived an hour or more late.
- That ranks #6 of 6 airlines on this route, which averaged 78% on time overall.
- The largest source of delay minutes was late-arriving aircraft (42%).
On-time trend by month
Why this airline's flights were late
- Late-arriving aircraft42%
- Airline (crew, maintenance, cleaning, fueling)29%
- Air traffic control & airport congestion26%
- Extreme weather2%
- Security1%
Other airlines on SEA to DEN
- United Airlines88% on time · 9 min avg delay
- Alaska Airlines78% on time · 12 min avg delay
- Delta Air Lines73% on time · 17 min avg delay
- Frontier Airlines77% on time · 15 min avg delay
- SkyWest Airlines85% on time · 10 min avg delay
Full SEA to DEN comparison →
Southwest Airlines on-time record across all routes →
1,345 Southwest Airlines flights tracked on this route; 8 cancelled, 7 diverted.
Data: U.S. DOT Bureau of Transportation Statistics, Aug 2025 – Jul 2026 (12 months). Latest month published by BTS: July 2026. How we calculate this.