Route Reliability

Route reliability

Seattle (SEA) to Chicago (ORD): 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 Chicago, IL (ORD), September 2025 to August 2026.

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

Seattle, WAChicago, IL

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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 ORD

Seattle, WA to Chicago, IL

On time
75.0%vs 75.6% U.S. average About average
Cancelled
1.2%vs 1.9% U.S. average Better than average
60+ min late
8.2%vs 8.1% U.S. average About average
Scheduled flights
5,538in 12 months4 airlines
Most reliable airline
United Airlines80.4% on time · 1,488 flights

On time about as often as 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 ORD, 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 80.4% 0.8% 7.5% 88 min 0.7% 1,488
2. American Airlines 73.7% 1.6% 9.1% 102 min 1.0% 1,353
3. Delta Air Lines 73.4% 1.3% 9.3% 73 min 1.7% 922
4. Alaska Airlines 72.3% 1.1% 7.5% 59 min 0.8% 1,775

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 Seattle (SEA) to Chicago (ORD): 80.4% of its 1,488 scheduled flights arrived within 15 minutes of schedule, compared with 72.3% for Alaska Airlines.
  • 1.2% of flights on this route were cancelled (about 1 in 83), 0.7 points lower than the U.S. average of 1.9%.
  • 8.2% of flights, about 1 in 12, arrived an hour or more late. When a flight was late (15+ minutes), the average arrival delay was 79 min.
  • Overall, 75.0% of flights on this route arrived on time, 0.6 points lower than the U.S. average of 75.6%.
  • Over the last 3 years, February was the most reliable month on this route (85.1% on time) and July the least reliable (65.8%).
  • Cancellations peaked in January, when 2.6% of flights were cancelled.
  • Flights scheduled to depart 6 am to 7 am were the most punctual (87.8% on time); flights scheduled to depart 1 pm to 2 pm were the least (57.8%).
  • In the other direction, Chicago (ORD) to Seattle (SEA), 66.4% of flights were on time and 1.4% were cancelled. Compare airlines ORD to SEA.

Best and worst months to fly SEA to ORD

Jan 72.9%
Feb 85.1%
Mar 81.7%
Apr 80.0%
May 75.3%
Jun 71.9%
Jul 65.8%
Aug 66.2%
Sep 78.9%
Oct 84.3%
Nov 81.4%
Dec 78.9%
Share of scheduled flights on time 12-month average 75.0%
All airlines combined, by calendar month, September 2023 to August 2026 (3 years pooled). Scale starts at zero.
Show as table
PeriodOn timeFlights
January 72.9% 856
February 85.1% 807
March 81.7% 1,000
April 80.0% 1,289
May 75.3% 1,564
June 71.9% 1,675
July 65.8% 1,806
August 66.2% 1,736
September 78.9% 1,486
October 84.3% 1,363
November 81.4% 1,110
December 78.9% 1,082
Best and worst calendar month by airline, September 2023 to August 2026.
AirlineBest monthWorst month
United Airlines February (91.9%) July (71.6%)
American Airlines October (83.5%) August (64.0%)
Delta Air Lines October (88.7%) January (64.7%)
Alaska Airlines February (84.5%) July (56.9%)

Month by month, last 12 months

Sep 79.6%
Oct 80.2%
Nov 71.3%
Dec 68.8%
Jan 72.1%
Feb 91.3%
Mar 76.5%
Apr 77.8%
May 80.6%
Jun 70.6%
Jul 67.9%
Aug 69.5%
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 79.6% 509
Oct 2025 80.2% 496
Nov 2025 71.3% 390
Dec 2025 68.8% 382
Jan 2026 72.1% 301
Feb 2026 91.3% 300
Mar 2026 76.5% 357
Apr 2026 77.8% 465
May 2026 80.6% 562
Jun 2026 70.6% 582
Jul 2026 67.9% 608
Aug 2026 69.5% 586

Best and worst departure times

<6a 80.3%
6a 87.8%
7a 84.7%
8a 74.2%
9a Insufficient sample
10a 70.7%
11a 60.1%
12p 70.4%
1p 57.8%
2p 67.2%
3p 68.2%
4p 85.2%
5p 75.6%
6p Insufficient sample
10p 89.6%
11p 85.2%
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 80.3% 427
Departing 6 am to 7 am 87.8% 262
Departing 7 am to 8 am 84.7% 805
Departing 8 am to 9 am 74.2% 360
Departing 9 am to 10 am Insufficient sample 28
Departing 10 am to 11 am 70.7% 935
Departing 11 am to noon 60.1% 263
Departing noon to 1 pm 70.4% 115
Departing 1 pm to 2 pm 57.8% 464
Departing 2 pm to 3 pm 67.2% 247
Departing 3 pm to 4 pm 68.2% 239
Departing 4 pm to 5 pm 85.2% 81
Departing 5 pm to 6 pm 75.6% 796
Departing 6 pm to 7 pm Insufficient sample 31
Departing 10 pm to 11 pm 89.6% 67
Departing 11 pm to midnight 85.2% 418
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 Chicago, IL (ORD), 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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