Route Reliability

Route reliability

Chicago (ORD) to Seattle (SEA): which airline is most on time?

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

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

Chicago, ILSeattle, 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

ORD to SEA

Chicago, IL to Seattle, WA

On time
66.4%vs 75.6% U.S. average Worse than average
Cancelled
1.4%vs 1.9% U.S. average Better than average
60+ min late
10.3%vs 8.1% U.S. average Worse than average
Scheduled flights
5,542in 12 months4 airlines
Most reliable airline
United Airlines73.5% on time · 1,489 flights

On time less 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 ORD 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 73.5% 0.6% 6.9% 59 min 0.1% 1,489
2. Delta Air Lines 64.6% 1.4% 9.7% 67 min 0.7% 922
3. Alaska Airlines 64.1% 1.8% 12.0% 68 min 0.2% 1,778
4. American Airlines 63.0% 1.6% 12.3% 68 min 0.1% 1,353

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 Chicago (ORD) to Seattle (SEA): 73.5% of its 1,489 scheduled flights arrived within 15 minutes of schedule, compared with 63.0% for American Airlines.
  • 1.4% of flights on this route were cancelled (about 1 in 71), 0.5 points lower than the U.S. average of 1.9%.
  • 10.3% of flights, about 1 in 10, arrived an hour or more late. When a flight was late (15+ minutes), the average arrival delay was 66 min.
  • Overall, 66.4% of flights on this route arrived on time, 9.2 points lower than the U.S. average of 75.6%.
  • Over the last 3 years, September was the most reliable month on this route (83.4% on time) and June the least reliable (64.8%).
  • Cancellations peaked in January, when 2.9% of flights were cancelled.
  • Flights scheduled to depart 6 am to 7 am were the most punctual (80.7% on time); flights scheduled to depart 10 pm to 11 pm were the least (45.3%).
  • In the other direction, Seattle (SEA) to Chicago (ORD), 75.0% of flights were on time and 1.2% were cancelled. Compare airlines SEA to ORD.

Best and worst months to fly ORD to SEA

Jan 69.5%
Feb 78.6%
Mar 67.6%
Apr 80.1%
May 74.9%
Jun 64.8%
Jul 65.6%
Aug 65.3%
Sep 83.4%
Oct 82.0%
Nov 75.8%
Dec 70.9%
Share of scheduled flights on time 12-month average 66.4%
All airlines combined, by calendar month, September 2023 to August 2026 (3 years pooled). Scale starts at zero.
Show as table
PeriodOn timeFlights
January 69.5% 856
February 78.6% 807
March 67.6% 999
April 80.1% 1,289
May 74.9% 1,564
June 64.8% 1,676
July 65.6% 1,805
August 65.3% 1,740
September 83.4% 1,490
October 82.0% 1,363
November 75.8% 1,109
December 70.9% 1,085
Best and worst calendar month by airline, September 2023 to August 2026.
AirlineBest monthWorst month
United Airlines September (89.4%) August (69.8%)
Delta Air Lines September (87.9%) January (65.9%)
Alaska Airlines April (80.8%) June (60.1%)
American Airlines September (82.8%) March (57.1%)

Month by month, last 12 months

Sep 83.7%
Oct 73.8%
Nov 59.3%
Dec 46.6%
Jan 64.5%
Feb 73.1%
Mar 49.3%
Apr 74.6%
May 73.1%
Jun 66.5%
Jul 63.5%
Aug 60.9%
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 83.7% 509
Oct 2025 73.8% 496
Nov 2025 59.3% 391
Dec 2025 46.6% 384
Jan 2026 64.5% 301
Feb 2026 73.1% 301
Mar 2026 49.3% 357
Apr 2026 74.6% 465
May 2026 73.1% 562
Jun 2026 66.5% 582
Jul 2026 63.5% 608
Aug 2026 60.9% 586

Best and worst departure times

6a 80.7%
7a 77.4%
8a 73.9%
9a 71.6%
10a 63.4%
11a 70.1%
12p 68.8%
1p 78.3%
2p 59.3%
3p 63.4%
4p 70.8%
5p 51.2%
6p 55.1%
7p 58.3%
8p 48.0%
9p 55.4%
10p 45.3%
Share of scheduled flights on time
By scheduled local departure hour at ORD, September 2025 to August 2026. Hours with no scheduled flights are omitted. Scale starts at zero.
Show as table
PeriodOn timeFlights
Departing 6 am to 7 am 80.7% 481
Departing 7 am to 8 am 77.4% 642
Departing 8 am to 9 am 73.9% 528
Departing 9 am to 10 am 71.6% 215
Departing 10 am to 11 am 63.4% 290
Departing 11 am to noon 70.1% 231
Departing noon to 1 pm 68.8% 160
Departing 1 pm to 2 pm 78.3% 429
Departing 2 pm to 3 pm 59.3% 209
Departing 3 pm to 4 pm 63.4% 377
Departing 4 pm to 5 pm 70.8% 295
Departing 5 pm to 6 pm 51.2% 406
Departing 6 pm to 7 pm 55.1% 334
Departing 7 pm to 8 pm 58.3% 333
Departing 8 pm to 9 pm 48.0% 358
Departing 9 pm to 10 pm 55.4% 148
Departing 10 pm to 11 pm 45.3% 106
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 Chicago, IL (ORD) 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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