Southwest Airlines STL to SLC on-time performance
Southwest Airlines nonstop flights from St. Louis to Salt Lake City · Aug 2025 – Jul 2026
On-time arrivals
67%
arrived < 15 min late
Cancelled
0.0%
0 flights
Avg arrival delay
15 min
40 min when late
Rank on route
#3 of 3
route average 87% on time
Key facts
- Southwest Airlines flights on STL to SLC arrived on time 67% of the time in Aug 2025 – Jul 2026.
- 0% were cancelled, and 0% arrived an hour or more late.
- That ranks #3 of 3 airlines on this route, which averaged 87% on time overall.
- The largest source of delay minutes was extreme weather (58%).
On-time trend by month
Why this airline's flights were late
- Extreme weather58%
- Late-arriving aircraft31%
- Airline (crew, maintenance, cleaning, fueling)12%
- Air traffic control & airport congestion0%
- Security0%
Other airlines on STL to SLC
- Delta Air Lines88% on time · 14 min avg delay
- SkyWest Airlines100% on time · 0 min avg delay
Full STL to SLC comparison →
Southwest Airlines on-time record across all routes →
9 Southwest Airlines flights tracked on this route; 0 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.