SEA to SLC flight delays & on-time performance
Nonstop flights from Seattle–Tacoma International Airport to Salt Lake City International Airport · 689 miles · Aug 2025 – Jul 2026
No FAA-reported ground stops or delays at SEA or SLC right now. Individual flights can still be delayed by the airline; check with your airline for your flight.
Key facts
- Flights from Seattle (SEA) to Salt Lake City (SLC) arrived on time 84% of the time in Aug 2025 – Jul 2026, better than the 78% national average.
- 0.8% were cancelled, and 4% arrived an hour or more late.
- Delta Air Lines was the most punctual airline here (87% on time); SkyWest Airlines was the least (80%).
- Departures scheduled around 7am did best (94% on time); around 11am did worst (78%).
- Tuesday was the most reliable day to fly (86% on time) and Thursday the least (80%).
- The largest source of delay minutes was airline (crew, maintenance, cleaning, fueling) (48%).
Which airline is most on time from SEA 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 |
|---|---|---|---|---|---|
| Delta Air Lines | 87% | 0.5% | 9 min | 4.2% | 2,227 |
| Alaska Airlines | 80% | 1.4% | 10 min | 3.8% | 1,420 |
| SkyWest AirlinesRegional airline operating flights for United Express, Delta Connection, American Eagle and Alaska. | 80% | 0.0% | 10 min | 5.2% | 387 |
| Frontier Airlines | 74% | 3.3% | 16 min | 10.3% | 90 |
Best time of day to fly
On-time arrival rate by scheduled departure hour (local time).
- 5am94%365 flights
- 7am94%385 flights
- 8am90%150 flights
- 9am87%444 flights
- 10am91%43 flights
- 11am78%635 flights
- 12pm81%48 flights
- 1pm83%376 flights
- 2pm78%107 flights
- 3pm79%115 flights
- 4pm80%348 flights
- 5pm81%297 flights
- 6pm80%261 flights
- 7pm78%354 flights
- 8pm79%195 flights
Best day of the week
On-time arrival rate by day of departure.
- Monday84%0.8% cancelled
- Tuesday86%0.2% cancelled
- Wednesday85%0.2% cancelled
- Thursday80%1.2% cancelled
- Friday83%1.8% cancelled
- Saturday84%1.0% cancelled
- Sunday83%0.7% 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)48%
- Late-arriving aircraft39%
- Air traffic control & airport congestion12%
- Extreme weather2%
- Security0%
Why flights are cancelled
Share of cancellations by reason.
- Airline (crew, maintenance, cleaning, fueling)46%
- Extreme weather37%
- Air traffic control & airport congestion17%
- Security0%
SEA to SLC: common questions
- How often are SEA to SLC flights on time?
- 84% 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 Seattle to Salt Lake City cancelled?
- 0.8% of scheduled flights were cancelled (35 of 4,124).
- How long are typical delays?
- Across all flights the average arrival delay was 9 min (early arrivals count as zero). Flights that were late arrived 50 min behind schedule on average, and 4.3% of flights were an hour or more late.
- How long is taxi time at SEA?
- Flights on this route spent 20 min taxiing from the gate to takeoff on average.
Related routes
Return trip: SLC to SEA — 80% on time
More flights from Seattle
Data: U.S. DOT Bureau of Transportation Statistics, Aug 2025 – Jul 2026 (12 months). Latest month published by BTS: July 2026. Route: SEA → SLC, nonstop flights by US airlines that report to the DOT. How we calculate this.