Route reliability

Los Angeles (LAX) to Seattle (SEA): which airline is most on time?

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

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

Los Angeles, CASeattle, WA

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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

LAX to SEA

Los Angeles, CA to Seattle, WA

On time
84.2%vs 75.6% U.S. average Better than average
Cancelled
0.8%vs 1.9% U.S. average Better than average
60+ min late
4.6%vs 8.1% U.S. average Better than average
Scheduled flights
7,534in 12 months6 airlines
Most reliable airline
United Airlines89.1% on time · 376 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 LAX to SEA, 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. United Airlines Most reliable 89.1% 0.0% 1.9% 40 min 0.0% 376
2. Delta Air Lines 84.6% 0.7% 5.4% 71 min 0.1% 2,228
3. Alaska Airlines 84.4% 0.9% 3.6% 52 min 0.1% 3,292
4. SkyWest Airlines Operating carrier; sold as United Express, Delta Connection, American Eagle, Alaska 82.7% 0.7% 5.9% 72 min 0.2% 1,315
5. Frontier Airlines 80.5% 3.2% 5.2% 62 min 0.3% 308
American Airlines Insufficient sample (fewer than 50 flights) 15

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

United Airlines has the strongest record on this route.

  • United Airlines had the best on-time record from Los Angeles (LAX) to Seattle (SEA): 89.1% of its 376 scheduled flights arrived within 15 minutes of schedule, compared with 80.5% for Frontier Airlines.
  • American Airlines also flew this route but with fewer than 50 reported flights, too few to rate.
  • 0.8% of flights on this route were cancelled (about 1 in 125), 1.1 points lower than the U.S. average of 1.9%.
  • 4.6% of flights, about 1 in 22, arrived an hour or more late. When a flight was late (15+ minutes), the average arrival delay was 61 min.
  • Overall, 84.2% of flights on this route arrived on time, 8.6 points higher than the U.S. average of 75.6%.
  • Over the last 3 years, November was the most reliable month on this route (89.6% on time) and July the least reliable (78.6%).
  • Cancellations peaked in January, when 3.1% of flights were cancelled.
  • Flights scheduled to depart 6 am to 7 am were the most punctual (90.6% on time); flights scheduled to depart noon to 1 pm were the least (78.2%).
  • In the other direction, Seattle (SEA) to Los Angeles (LAX), 81.3% of flights were on time and 0.8% were cancelled. Compare airlines SEA to LAX.

Best and worst months to fly LAX to SEA

Jan 82.8%
Feb 86.5%
Mar 82.1%
Apr 86.9%
May 83.5%
Jun 78.8%
Jul 78.6%
Aug 79.7%
Sep 87.7%
Oct 87.5%
Nov 89.6%
Dec 83.0%
Share of scheduled flights on time 12-month average 84.2%
All airlines combined, by calendar month, September 2023 to August 2026 (3 years pooled). Scale starts at zero.
Show as table
PeriodOn timeFlights
January 82.8% 1,716
February 86.5% 1,617
March 82.1% 1,822
April 86.9% 1,804
May 83.5% 1,960
June 78.8% 1,927
July 78.6% 2,005
August 79.7% 2,045
September 87.7% 1,955
October 87.5% 1,949
November 89.6% 1,801
December 83.0% 1,821
Best and worst calendar month by airline, September 2023 to August 2026.
AirlineBest monthWorst month
United Airlines October (93.6%) June (71.7%)
Delta Air Lines September (91.7%) August (81.2%)
Alaska Airlines November (89.6%) July (76.2%)
SkyWest Airlines November (90.8%) December (76.8%)

Month by month, last 12 months

Sep 92.1%
Oct 87.6%
Nov 89.4%
Dec 80.3%
Jan 85.1%
Feb 86.8%
Mar 82.9%
Apr 86.9%
May 85.4%
Jun 78.2%
Jul 80.1%
Aug 77.7%
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 92.1% 606
Oct 2025 87.6% 612
Nov 2025 89.4% 604
Dec 2025 80.3% 629
Jan 2026 85.1% 562
Feb 2026 86.8% 555
Mar 2026 82.9% 638
Apr 2026 86.9% 613
May 2026 85.4% 679
Jun 2026 78.2% 651
Jul 2026 80.1% 668
Aug 2026 77.7% 717

Best and worst departure times

<6a Insufficient sample
6a 90.6%
7a 89.8%
8a 87.3%
9a 88.0%
10a 85.5%
11a 85.1%
12p 78.2%
1p 84.4%
2p 84.4%
3p 82.2%
4p 83.2%
5p 86.5%
6p 78.4%
7p 78.7%
8p 84.7%
9p 82.4%
Share of scheduled flights on time
By scheduled local departure hour at LAX, 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 Insufficient sample 1
Departing 6 am to 7 am 90.6% 224
Departing 7 am to 8 am 89.8% 630
Departing 8 am to 9 am 87.3% 455
Departing 9 am to 10 am 88.0% 599
Departing 10 am to 11 am 85.5% 311
Departing 11 am to noon 85.1% 518
Departing noon to 1 pm 78.2% 412
Departing 1 pm to 2 pm 84.4% 366
Departing 2 pm to 3 pm 84.4% 506
Departing 3 pm to 4 pm 82.2% 617
Departing 4 pm to 5 pm 83.2% 380
Departing 5 pm to 6 pm 86.5% 616
Departing 6 pm to 7 pm 78.4% 422
Departing 7 pm to 8 pm 78.7% 837
Departing 8 pm to 9 pm 84.7% 418
Departing 9 pm to 10 pm 82.4% 222
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 Los Angeles, CA (LAX) to Seattle, WA (SEA), 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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