Southwest Airlines DEN to BOS on-time performance
Southwest Airlines nonstop flights from Denver to Boston · Aug 2025 – Jul 2026
On-time arrivals
58%
arrived < 15 min late
Cancelled
1.1%
10 flights
Avg arrival delay
28 min
65 min when late
Rank on route
#4 of 4
route average 71% on time
Key facts
- Southwest Airlines flights on DEN to BOS arrived on time 58% of the time in Aug 2025 – Jul 2026.
- 1.1% were cancelled, and 16% arrived an hour or more late.
- That ranks #4 of 4 airlines on this route, which averaged 71% on time overall.
- The largest source of delay minutes was air traffic control & airport congestion (39%).
On-time trend by month
Why this airline's flights were late
- Air traffic control & airport congestion39%
- Late-arriving aircraft38%
- Airline (crew, maintenance, cleaning, fueling)22%
- Extreme weather2%
- Security0%
Other airlines on DEN to BOS
- United Airlines77% on time · 17 min avg delay
- JetBlue68% on time · 28 min avg delay
- Delta Air Lines74% on time · 16 min avg delay
Full DEN to BOS comparison →
Southwest Airlines on-time record across all routes →
914 Southwest Airlines flights tracked on this route; 10 cancelled, 1 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.