Best Time to Fly SEA to ORD: On-Time Stats by Hour & Airline
Seattle/Tacoma International → Chicago O'Hare International
Data through July 2026 · Last updated October 18, 2026
Over the last 12 months, 75.6% of Seattle (SEA) to Chicago (ORD) flights arrived on time (5,551 scheduled flights). That is 2.0 points below the national average of 77.6%.
United Airlines was the most punctual of the 4 airlines on the route at 80.3%, while Alaska Airlines trailed at 72.8%.
February has been the best month (86% on time) and Sunday the weakest day of the week (73%).
1.3% of flights were cancelled, versus 1.8% nationally.
SEA to ORD on-time performance by airline
Last 12 months. Airlines with fewer than 30 completed flights are marked “limited data”.
| Airline | On time | Avg delay when late | Cancelled | Flights |
|---|---|---|---|---|
| United Airlines | 80.3% | 89 min | 0.9% | 1,503 |
| Delta Air Lines | 77.2% | 73 min | 1.2% | 907 |
| American Airlines | 73.0% | 101 min | 1.9% | 1,350 |
| Alaska Airlines | 72.8% | 57 min | 1.3% | 1,791 |
80%+ good 70–79.9% fair <70% poor
Best time of day to fly SEA to ORD
On-time arrival % by scheduled departure hour (local time), 10,772 flights over 24 months.
Show the numbers
| Departure hour | On time | Cancelled | Flights |
|---|---|---|---|
| 12am–1am | 81.1% | 2.5% | 609 |
| 5am–6am | Limited data | 29 | |
| 6am–7am | 92.8% | 0.6% | 663 |
| 7am–8am | 85.6% | 0.5% | 1,516 |
| 8am–9am | 76.7% | 0.7% | 585 |
| 9am–10am | 87.2% | 2.1% | 48 |
| 10am–11am | 72.2% | 1.0% | 1,547 |
| 11am–12pm | 72.2% | 0.4% | 768 |
| 12pm–1pm | 63.5% | 0.4% | 251 |
| 1pm–2pm | 56.4% | 0.9% | 918 |
| 2pm–3pm | 71.0% | 1.2% | 424 |
| 3pm–4pm | 63.0% | 1.5% | 340 |
| 4pm–5pm | 76.4% | 0.0% | 176 |
| 5pm–6pm | 79.7% | 1.0% | 1,300 |
| 6pm–7pm | 78.9% | 0.3% | 347 |
| 7pm–8pm | Limited data | 1 | |
| 10pm–11pm | 76.7% | 0.5% | 216 |
| 11pm–12am | 82.0% | 1.2% | 1,034 |
Best day of the week
24 months, by day of departure.
Best month to fly
24 months, by calendar month.
Holiday travel on SEA to ORD
On-time arrivals during holiday periods compared with all other days, last 24 months.
| Period | On time | vs other days | Cancelled | Flights |
|---|---|---|---|---|
| Thanksgiving week (Tue before to Mon after) | 67.3% | -12.4 pts | 5.0% | 179 |
| Christmas & New Year (Dec 20 - Jan 3) | 81.6% | +2.0 pts | 0.8% | 362 |
| Summer peak (Jun 15 - Aug 15) | 66.6% | -13.0 pts | 1.0% | 2,445 |
| All other days | 79.7% | — | 0.8% | 7,786 |
Monthly on-time trend
On-time arrival % each month, with the 12-month US average for reference.
What causes delays on this route
Share of reported delay minutes, last 12 months (BTS cause categories).