Southwest Airlines DEN to ONT on-time performance
Southwest Airlines nonstop flights from Denver to Ontario · Aug 2025 – Jul 2026
On-time arrivals
70%
arrived < 15 min late
Cancelled
0.1%
1 flights
Avg arrival delay
16 min
49 min when late
Rank on route
#3 of 3
route average 75% on time
Key facts
- Southwest Airlines flights on DEN to ONT arrived on time 70% of the time in Aug 2025 – Jul 2026.
- 0.1% were cancelled, and 8% arrived an hour or more late.
- That ranks #3 of 3 airlines on this route, which averaged 75% on time overall.
- The largest source of delay minutes was late-arriving aircraft (57%).
On-time trend by month
Why this airline's flights were late
- Late-arriving aircraft57%
- Airline (crew, maintenance, cleaning, fueling)34%
- Air traffic control & airport congestion8%
- Extreme weather1%
- Security0%
Other airlines on DEN to ONT
- United Airlines80% on time · 15 min avg delay
- Frontier Airlines80% on time · 13 min avg delay
Full DEN to ONT comparison →
Southwest Airlines on-time record across all routes →
1,268 Southwest Airlines flights tracked on this route; 1 cancelled, 0 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.