STL to SLC flight delays & on-time performance
Nonstop flights from St. Louis Lambert International Airport to Salt Lake City International Airport · 1,156 miles · Aug 2025 – Jul 2026
No FAA-reported ground stops or delays at STL or SLC right now. Individual flights can still be delayed by the airline; check with your airline for your flight.
Key facts
- Flights from St. Louis (STL) to Salt Lake City (SLC) arrived on time 87% of the time in Aug 2025 – Jul 2026, better than the 78% national average.
- 0.9% were cancelled, and 5% arrived an hour or more late.
- Departures scheduled around 8am did best (94% on time); around 7pm did worst (82%).
- Wednesday was the most reliable day to fly (92% on time) and Saturday the least (81%).
- The largest source of delay minutes was airline (crew, maintenance, cleaning, fueling) (57%).
Which airline is most on time from STL to SLC?
Ranked by on-time arrival rate. Regional airlines fly under their partner's brand (e.g. SkyWest for Delta Connection or United Express).
| Airline | On time | Cancelled | Avg delay | 1 hr+ late | Flights |
|---|---|---|---|---|---|
| SkyWest AirlinesRegional airline operating flights for United Express, Delta Connection, American Eagle and Alaska. | 100% | 0.0% | 0 min | 0.0% | 2 |
| Delta Air Lines | 88% | 0.9% | 14 min | 5.4% | 979 |
| Southwest Airlines | 67% | 0.0% | 15 min | 0.0% | 9 |
Best time of day to fly
On-time arrival rate by scheduled departure hour (local time).
- 6am86%100 flights
- 7am93%210 flights
- 8am94%55 flights
- 2pm87%302 flights
- 5pm90%60 flights
- 6pm83%76 flights
- 7pm82%161 flights
- 8pm81%16 flights
Best day of the week
On-time arrival rate by day of departure.
- Monday84%1.4% cancelled
- Tuesday90%0.0% cancelled
- Wednesday92%0.0% cancelled
- Thursday90%1.4% cancelled
- Friday90%0.7% cancelled
- Saturday81%0.0% cancelled
- Sunday83%2.8% cancelled
On-time trend by month
Why flights are late
Share of delay minutes by cause, as reported by airlines to the DOT.
- Airline (crew, maintenance, cleaning, fueling)57%
- Late-arriving aircraft26%
- Extreme weather10%
- Air traffic control & airport congestion7%
- Security0%
Why flights are cancelled
Share of cancellations by reason.
- Airline (crew, maintenance, cleaning, fueling)78%
- Extreme weather22%
- Air traffic control & airport congestion0%
- Security0%
STL to SLC: common questions
- How often are STL to SLC flights on time?
- 87% of flights arrived less than 15 minutes late in Aug 2025 – Jul 2026, compared with 78% for all US flights.
- How often are flights from St. Louis to Salt Lake City cancelled?
- 0.9% of scheduled flights were cancelled (9 of 990).
- How long are typical delays?
- Across all flights the average arrival delay was 14 min (early arrivals count as zero). Flights that were late arrived 102 min behind schedule on average, and 5.3% of flights were an hour or more late.
- How long is taxi time at STL?
- Flights on this route spent 13 min taxiing from the gate to takeoff on average.
Related routes
Return trip: SLC to STL — 85% on time
More flights from St. Louis
Data: U.S. DOT Bureau of Transportation Statistics, Aug 2025 – Jul 2026 (12 months). Latest month published by BTS: July 2026. Route: STL → SLC, nonstop flights by US airlines that report to the DOT. How we calculate this.