Southwest Airlines BOS to DEN on-time performance
Southwest Airlines nonstop flights from Boston to Denver · Aug 2025 – Jul 2026
On-time arrivals
66%
arrived < 15 min late
Cancelled
1.0%
9 flights
Avg arrival delay
20 min
54 min when late
Rank on route
#4 of 4
route average 77% on time
Key facts
- Southwest Airlines flights on BOS to DEN arrived on time 66% of the time in Aug 2025 – Jul 2026.
- 1% were cancelled, and 10% arrived an hour or more late.
- That ranks #4 of 4 airlines on this route, which averaged 77% on time overall.
- The largest source of delay minutes was late-arriving aircraft (52%).
On-time trend by month
Why this airline's flights were late
- Late-arriving aircraft52%
- Airline (crew, maintenance, cleaning, fueling)23%
- Air traffic control & airport congestion21%
- Extreme weather4%
- Security0%
Other airlines on BOS to DEN
- United Airlines83% on time · 12 min avg delay
- JetBlue71% on time · 19 min avg delay
- Delta Air Lines84% on time · 9 min avg delay
Full BOS to DEN comparison →
Southwest Airlines on-time record across all routes →
914 Southwest Airlines flights tracked on this route; 9 cancelled, 6 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.