PlainFlights

SEA vs SLC - Airport Comparison

Select two airports to compare on-time performance, delays, cancellations, and top routes using U.S. Department of Transportation Bureau of Transportation Statistics (BTS) data (2020–2025) across all 50 states. See our methodology for how metrics are computed.

Airport A
SEA

Seattle, WA

Seattle, Washington

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Airport B
SLC

Salt Lake City, UT

Salt Lake City, Utah

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Key Performance Metrics

BTS on-time performance data, 2020–2025 cumulative.

Metric SEA SLC
On-Time Rate (higher is better) 83.1% 85.8%
Avg Delay (lower is better) 63.4 min 76.0 min
Delay Rate (lower is better) 16.9% 14.2%
Cancellation Rate (lower is better) 0.73% 0.57%
Total Flights 1,871,155 1,319,985
Delayed Flights 315,819 186,884
Cancelled Flights 13,720 7,511
Top Delay Cause Carrier Carrier

✓ / ▲ indicates the more favorable value. Data: BTS On-Time Performance, 2020–2025.

Delay Cause Breakdown

SEA - Seattle, WA

Carrier 44.3%
Late Aircraft 28.6%
NAS 21.0%
Weather 5.8%
Security 0.3%

SLC - Salt Lake City, UT

Carrier 50.6%
Late Aircraft 25.1%
NAS 16.2%
Weather 8.1%
Security 0.1%

Top Routes

Top routes from SEA

Route Flights On-Time
SEA → LAX
Los Angeles
41,859 84%
LAX → SEA
Seattle
41,819 86.2%
SEA → ANC
Anchorage
41,143 77.5%
ANC → SEA
Seattle
41,064 85.8%
PHX → SEA
Seattle
38,561 84.3%
SEA → PHX
Phoenix
38,549 82.3%

Top routes from SLC

Route Flights On-Time
DEN → SLC
Salt Lake City
43,089 78.3%
SLC → DEN
Denver
43,051 78.8%
SLC → PHX
Phoenix
30,395 83.2%
PHX → SLC
Salt Lake City
30,355 84.5%
LAX → SLC
Salt Lake City
27,163 87.1%
SLC → LAX
Los Angeles
27,094 84.2%

Source: Bureau of Transportation Statistics (BTS), On-Time Performance Data (2020–2025) Bureau of Transportation Statistics (BTS), On-Time Performance Data (2020–2025) On-time rates exclude cancelled and diverted flights. PlainFlights is not affiliated with BTS or the DOT

Every figure on PlainFlights is rendered directly from BTS On-Time Performance data, no number is typed in by an editor. This tool queries live on-time, delay, and cancellation figures for the two selected airports from the dataset. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error.