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Route · SLC → SEA · 2020–2025 BTS data

Salt Lake City to Seattle

The SLC–SEA corridor (Salt Lake City, UT → Seattle, WA) runs ahead of the national average, served by 21 carriers across roughly 689 miles.

Data updated 2026-06-13

84%
On-time
+5 pts
vs US avg
59 min
Delay when late
22,741
Flights

Cancelled

0.8%

Best Month

Oct 2024 91%

Worst Month

Jun 2025 67%

Distance

689 mi

Carriers

21

Monthly Performance

Recent 24 months of route data.

Period Flights Delayed Cancelled Diverted Carriers
Dec 2025 303 88 1 2 DL,F9,AS,OO
Nov 2025 299 48 9 1 OO,DL,F9,AS
Oct 2025 367 74 5 0 AS,OO,DL,F9
Sep 2025 398 71 1 1 OO,DL,F9,AS
Aug 2025 409 113 5 0 OO,F9,AS,DL
Jul 2025 394 101 4 0 AS,OO,DL,F9
Jun 2025 373 123 2 0 AS,OO,DL,F9
May 2025 360 93 1 1 AS,OO,DL,F9
Apr 2025 307 53 1 0 DL,F9,OO,AS
Mar 2025 306 52 1 2 AS,OO,DL,F9
Feb 2025 281 46 3 0 AS,OO,DL,F9
Jan 2025 319 54 0 2 AS,OO,DL,F9
Dec 2024 304 37 0 0 AS,DL,F9,OO
Nov 2024 317 32 2 1 OO,AS,DL,F9
Oct 2024 335 29 1 1 AS,OO,DL,F9
Sep 2024 367 56 0 0 OO,AS,DL
Aug 2024 383 108 2 1 AS,DL,OO
Jul 2024 397 113 10 0 AS,DL,OO
Jun 2024 382 102 0 0 AS,DL,OO
May 2024 364 69 0 0 AS,DL,OO
Apr 2024 306 40 0 0 AS,DL,OO
Mar 2024 275 38 1 0 AS,DL,OO
Feb 2024 269 30 0 1 AS,DL,OO
Jan 2024 286 73 14 1 AS,DL,OO

Cancellation Rate

0.8%

63 of 8,101 flights

Diversion Rate

0.2%

14 of 8,101 flights

What the Data Says About SLC to SEA

Bureau of Transportation Statistics records show Salt Lake City to Seattle (SLC to SEA) running a 84% on-time rate over 22,741 tracked flights, on the stronger end of a typical domestic pairing. When flights do run late, the average delay is 59.0 minutes. The 689-mile corridor is served by 21 carriers, and over the last 24 months 0.8% of 8,101 flights were cancelled, 0.2% diverted.

The monthly split is wide on this route: Oct 2024 posted the strongest performance at 91% on-time, while Jun 2025 came in at just 67% - a 24-point swing worth factoring into travel timing.

Frequently Asked Questions

How often are flights delayed from SLC to SEA?
Flights from Salt Lake City to Seattle have a 84% on-time rate based on 22,741 flights. The average delay is 59.0 minutes. The best recent month was Oct 2024 with 91% on-time.
What is the cancellation rate for SLC to SEA?
Over the last 24 months, 0.8% of flights on this route were cancelled (63 of 8,101 flights) and 0.2% were diverted.
How far is the flight from SLC to SEA?
The flight distance from Salt Lake City (SLC) to Seattle (SEA) is approximately 689 miles. This route is served by 21 carriers.
When is the best time to fly from SLC to SEA?
The best recent month for on-time performance was Oct 2024 (91% on-time). The worst was Jun 2025 (67% on-time). Consider booking during months with historically better performance.

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Data source

Data Source: Bureau of Transportation Statistics (BTS), On-Time Performance Data. Statistics reflect cumulative performance across all available reporting periods.

Data sourced from U.S. Department of Transportation Bureau of Transportation Statistics (BTS) On-Time Performance data. See our methodology for details. Retrieved and formatted by PlainFlights Editorial

Every figure on PlainFlights is rendered directly from BTS On-Time Performance data, no number is typed in by an editor. This page aggregates this specific route's on-time performance and monthly trend, live from the dataset. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error.