Route reliability

Seattle (SEA) to Portland (PDX): which airline is most on time?

On-time arrivals, cancellations and long delays for every airline that reported nonstop flights from Seattle, WA (SEA) to Portland, OR (PDX), September 2025 to August 2026.

Historical performance Official DOT data through August 2026 · Not live flight status

Seattle, WAPortland, OR

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Three-letter airport codes, nonstop U.S. domestic flights. One direction at a time.

Route at a glance · September 2025 to August 2026

SEA to PDX

Seattle, WA to Portland, OR

On time
81.6%vs 75.6% U.S. average Better than average
Cancelled
0.7%vs 1.9% U.S. average Better than average
60+ min late
3.9%vs 8.1% U.S. average Better than average
Scheduled flights
4,826in 12 months3 airlines
Most reliable airline
SkyWest Airlines84.1% on time · 3,375 flights

On time more often than the U.S. average, with fewer cancellations.

Compared with all U.S. flights, September 2025 to August 2026. “About average” means within 1.5 points for on time, 0.3 for cancelled and 1 for 60+ minutes late.

Airlines on this route

Ranked by on-time arrival

Airlines from SEA to PDX, September 2025 to August 2026. Rates are shares of all scheduled flights.
Airline On time Cancelled 60+ min late Avg delay when late Diverted Flights
1. SkyWest Airlines Operating carrier; sold as United Express, Delta Connection, American Eagle, Alaska Most reliable 84.1% 0.6% 3.9% 52 min 0.0% 3,375
2. Delta Air Lines Small sample (under 300 flights) 76.3% 0.0% 4.4% 65 min 0.0% 249
3. Alaska Airlines 75.7% 1.3% 4.1% 42 min 0.0% 1,202

On time = arrived within 15 minutes of schedule. Avg delay when late = average arrival delay of flights 15+ minutes late. "Most reliable" needs at least 300 flights in 12 months. Tap a heading to sort.

What this means

SkyWest Airlines has the strongest record on this route.

  • SkyWest Airlines had the best on-time record from Seattle (SEA) to Portland (PDX): 84.1% of its 3,375 scheduled flights arrived within 15 minutes of schedule, compared with 75.7% for Alaska Airlines.
  • 0.7% of flights on this route were cancelled (about 1 in 143), 1.2 points lower than the U.S. average of 1.9%.
  • 3.9% of flights, about 1 in 26, arrived an hour or more late. When a flight was late (15+ minutes), the average arrival delay was 49 min.
  • Overall, 81.6% of flights on this route arrived on time, 6.0 points higher than the U.S. average of 75.6%.
  • Over the last 3 years, October was the most reliable month on this route (87.1% on time) and June the least reliable (73.5%).
  • Cancellations peaked in January, when 3.4% of flights were cancelled.
  • Flights scheduled to depart 7 am to 8 am were the most punctual (92.7% on time); flights scheduled to depart 10 pm to 11 pm were the least (70.2%).
  • In the other direction, Portland (PDX) to Seattle (SEA), 84.3% of flights were on time and 0.7% were cancelled. Compare airlines PDX to SEA.

Best and worst months to fly SEA to PDX

Jan 77.0%
Feb 81.4%
Mar 81.3%
Apr 85.7%
May 80.1%
Jun 73.5%
Jul 74.4%
Aug 75.7%
Sep 82.5%
Oct 87.1%
Nov 83.1%
Dec 77.5%
Share of scheduled flights on time 12-month average 81.6%
All airlines combined, by calendar month, September 2023 to August 2026 (3 years pooled). Scale starts at zero.
Show as table
PeriodOn timeFlights
January 77.0% 1,280
February 81.4% 1,175
March 81.3% 1,228
April 85.7% 1,222
May 80.1% 1,242
June 73.5% 1,198
July 74.4% 1,255
August 75.7% 1,306
September 82.5% 1,501
October 87.1% 1,458
November 83.1% 1,319
December 77.5% 1,209
Best and worst calendar month by airline, September 2023 to August 2026.
AirlineBest monthWorst month
SkyWest Airlines April (89.6%) January (78.4%)
Delta Air Lines May (89.0%) August (64.5%)
Alaska Airlines October (83.6%) July (56.8%)

Month by month, last 12 months

Sep 84.1%
Oct 87.4%
Nov 82.4%
Dec 73.3%
Jan 84.8%
Feb 87.0%
Mar 77.6%
Apr 90.4%
May 84.4%
Jun 81.9%
Jul 76.5%
Aug 71.2%
Share of scheduled flights on time U.S. average 75.6%
All airlines combined, September 2025 to August 2026. Scale starts at zero.
Show as table
PeriodOn timeFlights
Sep 2025 84.1% 433
Oct 2025 87.4% 428
Nov 2025 82.4% 403
Dec 2025 73.3% 378
Jan 2026 84.8% 402
Feb 2026 87.0% 361
Mar 2026 77.6% 397
Apr 2026 90.4% 374
May 2026 84.4% 391
Jun 2026 81.9% 403
Jul 2026 76.5% 426
Aug 2026 71.2% 430

Best and worst departure times

<6a 91.5%
7a 92.7%
8a 82.7%
9a 88.4%
10a 85.8%
11a 82.5%
12p 76.9%
1p 83.7%
2p 91.3%
3p 74.4%
4p 79.9%
5p 82.2%
6p 82.3%
7p 82.9%
8p 76.2%
9p 77.5%
10p 70.2%
11p 77.1%
Share of scheduled flights on time
By scheduled local departure hour at SEA, September 2025 to August 2026. Hours with no scheduled flights are omitted. Scale starts at zero.
Show as table
PeriodOn timeFlights
Departing before 6 am 91.5% 106
Departing 7 am to 8 am 92.7% 413
Departing 8 am to 9 am 82.7% 214
Departing 9 am to 10 am 88.4% 363
Departing 10 am to 11 am 85.8% 232
Departing 11 am to noon 82.5% 418
Departing noon to 1 pm 76.9% 169
Departing 1 pm to 2 pm 83.7% 313
Departing 2 pm to 3 pm 91.3% 92
Departing 3 pm to 4 pm 74.4% 387
Departing 4 pm to 5 pm 79.9% 269
Departing 5 pm to 6 pm 82.2% 241
Departing 6 pm to 7 pm 82.3% 277
Departing 7 pm to 8 pm 82.9% 187
Departing 8 pm to 9 pm 76.2% 223
Departing 9 pm to 10 pm 77.5% 347
Departing 10 pm to 11 pm 70.2% 352
Departing 11 pm to midnight 77.1% 223
Woman at an airport window watching a plane take off
Photo: Depositphotos (licensed stock, illustrative only). Credits

Sources & data dates

Source
U.S. DOT Bureau of Transportation Statistics, Reporting Carrier On-Time Performance (1987-present)
Period
September 2025 to August 2026 (12 months); month-of-year patterns September 2023 to August 2026
Data through
August 2026
Processed
2026-11-03
Scope
Nonstop scheduled flights from Seattle, WA (SEA) to Portland, OR (PDX), one direction. Airlines that report to the DOT only.
Method
Rates use all scheduled flights as the denominator; cancelled and diverted flights count as not on time. Figures based on fewer than 50 scheduled flights are suppressed. Full methodology.

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