FlightRecord

Seattle (SEA) to Chicago (ORD): On-Time Performance

Data through May 2026

The calendar drives reliability on SEA–ORD. February 2026 flights landed on schedule 92% of the time, but August 2025 dropped to 60% — a gap of 32 points. Across the full period the route averages 76% on-time against a national 78%.

On-time
76%
arrived <15 min late
Avg delay
16 min
completed flights
Cancelled
0.9%
Flights/day
15
last 12 months
Duration
4h 7m
scheduled
Distance
1,721 mi

Best airline from SEA to ORD

4 airlines flew this route regularly between 2024-06 and 2026-05.

AirlineOn-timeAvg delayCancelledFlights
United Airlinesmost reliable81%14 min0.9%3,086
Delta Air Lines78%15 min0.8%1,813
Alaska Airlines73%15 min0.6%3,631
American Airlines73%23 min1.5%2,149

Monthly on-time trend

Monthly on-time percentage for SEA to ORD flights50%75%100%June 2024: 76% on-time (522 flights)76Jun 2024July 2024: 67% on-time (575 flights)67August 2024: 71% on-time (551 flights)71September 2024: 79% on-time (483 flights)79Sep 2024October 2024: 86% on-time (435 flights)86November 2024: 87% on-time (357 flights)87December 2024: 84% on-time (366 flights)84Dec 2024January 2025: 78% on-time (283 flights)78February 2025: 80% on-time (259 flights)80March 2025: 85% on-time (331 flights)85Mar 2025April 2025: 80% on-time (426 flights)80May 2025: 80% on-time (536 flights)80June 2025: 71% on-time (571 flights)71Jun 2025July 2025: 64% on-time (623 flights)64August 2025: 60% on-time (599 flights)60September 2025: 80% on-time (509 flights)80Sep 2025October 2025: 81% on-time (496 flights)81November 2025: 74% on-time (390 flights)74December 2025: 70% on-time (382 flights)70Dec 2025January 2026: 73% on-time (301 flights)73February 2026: 92% on-time (300 flights)92March 2026: 79% on-time (357 flights)79Mar 2026April 2026: 79% on-time (465 flights)79May 2026: 81% on-time (562 flights)81

Best time to fly from SEA to ORD

Aim for departures around 5 a.m. (93% on-time); avoid 1 p.m. departures (58%).

On-time percentage by scheduled departure hour, SEA to ORD5 a.m.: 93% on-time (58 flights)56 a.m.: 93% on-time (626 flights)67 a.m.: 85% on-time (1,516 flights)78 a.m.: 78% on-time (585 flights)89 a.m.: 87% on-time (48 flights)910 a.m.: 72% on-time (1,388 flights)1011 a.m.: 73% on-time (823 flights)1112 p.m.: 59% on-time (343 flights)121 p.m.: 58% on-time (856 flights)132 p.m.: 70% on-time (448 flights)143 p.m.: 64% on-time (279 flights)154 p.m.: 76% on-time (167 flights)165 p.m.: 79% on-time (1,241 flights)176 p.m.: 76% on-time (406 flights)1810 p.m.: 73% on-time (298 flights)2211 p.m.: 81% on-time (1,009 flights)23scheduled departure hour

By day of week

DayOn-timeAvg delay
Monday74%18 min
Tuesdaybest80%16 min
Wednesday80%15 min
Thursday75%17 min
Friday74%16 min
Saturday78%14 min
Sunday73%18 min

What causes delays on this route

Share of total delay minutes by cause, as reported by carriers to the US DOT.

  • Late-arriving aircraft32%
  • Airline operations38%
  • National airspace system29%
  • Weather2%

Frequently asked questions

How often are flights from SEA to ORD delayed?
24% of SEA–ORD flights arrived 15 or more minutes late (the US DOT definition of a delay) between 2024-06 and 2026-05. The average arrival delay across completed flights was 16 minutes.
Which airline is most reliable from SEA to ORD?
United Airlines has the best on-time record on this route at 81%, based on 3,086 flights. 4 airlines flew SEA–ORD frequently enough to compare in this period.
What is the best time of day to fly from SEA to ORD?
Departures around 5 a.m. have the best record (93% on-time), while departures around 1 p.m. have the worst (58%). As on most US routes, delays accumulate through the day, so earlier flights are generally safer.
How long is the flight from SEA to ORD?
The scheduled SEA–ORD flight time averages 4h 7m over 1,721 miles. Actual arrival times vary — flights on this route land 15+ minutes late 24% of the time.
How often are SEA to ORD flights cancelled?
0.9% of scheduled flights on this route were cancelled between 2024-06 and 2026-05, at or below the national rate of 1.6%.
What is the worst month to fly from SEA to ORD?
August 2025 was the roughest month in this dataset, with only 60% of arrivals on time. The best was February 2026 at 92%. If your dates are flexible, that 32-point gap is worth planning around.

Based on 10,679 flights, 2024-062026-05. Source: US DOT Bureau of Transportation Statistics. Updated 2026-07-01.