Route on-time record
SEA to ORD: most on-time flights and the best time to fly
Seattle (Seattle–Tacoma International Airport) to Chicago (Chicago O'Hare International Airport). 5,555 nonstop flights in Jun 2025 to May 2026, 75% arrived within 15 minutes and 1.2% were cancelled. The most reliable flight number was United 2618 at 7:00 AM.
Flying on a specific date? We’ll adjust for the month, the weekday and the forecast.
SEA → ORD
Seattle to Chicago: 5,555 nonstop flights a year
On time (12 months)
75%
Cancelled
1.2%
avg delay 18 min
Best time to leave
Before 9 AM
85% on time vs 61% noon to 3 PM
Most reliable airline
United
79% chance on time
Fares open on our travel partner (Aviasales). Pick the flight number you chose here.
Most reliable nonstop flights
Ranked by the chance the flight operates and arrives within 15 minutes of schedule, from Jun 2025 to May 2026 records.
#1 · United 2618
7:00 AM → 1:12 PM4h 12m nonstop
Local times, typical schedule. Last flown 2026-05-31. Same departure also flew as United 1653; its record covers all of them.
90%
chance on time
- On time (history)
- 92%
- Cancelled
- 0.4%
- Avg arrival delay
- 10 min
- Arrived on time 92% of the time (226 flights, Jun 2025 to May 2026).
- Leaves in this route's most on-time window (Before 9 AM: 85% on time; Noon to 3 PM: 61%).
- Departs outside SEA's trouble window (4 PM to 10 PM, when 54% of its 68 ground stops and delay programs started).
Strong track record · 226 flights
Find United 2618 fares Opens this date on Aviasales#2 · American 2922
6:00 AM → 12:19 PM4h 19m nonstop
Local times, typical schedule. Last flown 2026-05-31.
88%
chance on time
- On time (history)
- 89%
- Cancelled
- 2.2%
- Avg arrival delay
- 11 min
- Arrived on time 89% of the time (131 flights, Jun 2025 to May 2026).
- Leaves in this route's most on-time window (Before 9 AM: 85% on time; Noon to 3 PM: 61%).
- Departs outside SEA's trouble window (4 PM to 10 PM, when 54% of its 68 ground stops and delay programs started).
Moderate track record · 131 flights
Find American 2922 fares Opens this date on Aviasales#3 · United 1763
10:53 PM → 5:03 AM4h 10m nonstop
Local times, typical schedule. Last flown 2026-05-20.
87%
chance on time
- On time (history)
- 94%
- Cancelled
- 2.7%
- Avg arrival delay
- 3 min
- Arrived on time 94% of the time (36 flights, Jun 2025 to May 2026).
- Departs outside SEA's trouble window (4 PM to 10 PM, when 54% of its 68 ground stops and delay programs started).
- Short track record (36 flights), so its score leans on the airline's record at this hour.
Limited track record · 36 flights
Find United 1763 fares Opens this date on Aviasales#4 · United 1503
5:00 PM → 11:07 PM4h 07m nonstop
Local times, typical schedule. Last flown 2026-05-31.
85%
chance on time
- On time (history)
- 100%
- Cancelled
- 0.0%
- Avg arrival delay
- 2 min
- Arrived on time 100% of the time (11 flights, Jun 2025 to May 2026).
- Departs inside SEA's trouble window: 54% of its 68 ground stops and delay programs started between 4 PM and 10 PM.
- Short track record (11 flights), so its score leans on the airline's record at this hour.
Limited track record · 11 flights
Find United 1503 fares Opens this date on Aviasales#5 · Delta 2055
7:15 AM → 1:23 PM4h 12m nonstop
Local times, typical schedule. Last flown 2026-05-31. Same departure also flew as Delta 1564; its record covers all of them.
84%
chance on time
- On time (history)
- 84%
- Cancelled
- 0.9%
- Avg arrival delay
- 9 min
- Arrived on time 84% of the time (329 flights, Jun 2025 to May 2026).
- Leaves in this route's most on-time window (Before 9 AM: 85% on time; Noon to 3 PM: 61%).
- Departs outside SEA's trouble window (4 PM to 10 PM, when 54% of its 68 ground stops and delay programs started).
Strong track record · 329 flights
Find Delta 2055 fares Opens this date on Aviasales#6 · Alaska 328
12:35 AM → 6:39 AM4h 11m nonstop
Local times, typical schedule. Last flown 2026-05-31.
80%
chance on time
- On time (history)
- 80%
- Cancelled
- 0.9%
- Avg arrival delay
- 10 min
- Arrived on time 80% of the time (230 flights, Jun 2025 to May 2026).
- Departs outside SEA's trouble window (4 PM to 10 PM, when 54% of its 68 ground stops and delay programs started).
Strong track record · 230 flights
Find Alaska 328 fares Opens this date on Aviasales#7 · American 885
7:00 AM → 1:17 PM4h 17m nonstop
Local times, typical schedule. Last flown 2026-05-20.
79%
chance on time
- On time (history)
- 84%
- Cancelled
- 2.1%
- Avg arrival delay
- 22 min
- Arrived on time 84% of the time (95 flights, Jun 2025 to May 2026).
- Leaves in this route's most on-time window (Before 9 AM: 85% on time; Noon to 3 PM: 61%).
- Departs outside SEA's trouble window (4 PM to 10 PM, when 54% of its 68 ground stops and delay programs started).
Moderate track record · 95 flights
Find American 885 fares Opens this date on Aviasales#8 · United 747
11:59 PM → 5:59 AM4h 05m nonstop
Local times, typical schedule. Last flown 2026-05-31. Same departure also flew as United 2651; its record covers all of them.
78%
chance on time
- On time (history)
- 80%
- Cancelled
- 1.2%
- Avg arrival delay
- 17 min
- Arrived on time 80% of the time (425 flights, Jun 2025 to May 2026).
- Departs outside SEA's trouble window (4 PM to 10 PM, when 54% of its 68 ground stops and delay programs started).
- 51% of its delay minutes came from the plane arriving late from an earlier flight.
Strong track record · 425 flights
Find United 747 fares Opens this date on Aviasales#9 · Alaska 265
8:30 AM → 2:56 PM4h 18m nonstop
Local times, typical schedule. Last flown 2026-05-31.
77%
chance on time
- On time (history)
- 82%
- Cancelled
- 1.0%
- Avg arrival delay
- 11 min
- Arrived on time 82% of the time (196 flights, Jun 2025 to May 2026).
- Leaves in this route's most on-time window (Before 9 AM: 85% on time; Noon to 3 PM: 61%).
- Departs outside SEA's trouble window (4 PM to 10 PM, when 54% of its 68 ground stops and delay programs started).
- Lands inside ORD's trouble window: 44% of its 243 ground stops and delay programs started between 2 PM and 8 PM.
Moderate track record · 196 flights
Find Alaska 265 fares Opens this date on Aviasales#10 · Alaska 538
5:42 PM → 11:59 PM4h 10m nonstop
Local times, typical schedule. Last flown 2026-05-31.
77%
chance on time
- On time (history)
- 78%
- Cancelled
- 0.9%
- Avg arrival delay
- 15 min
- Arrived on time 78% of the time (343 flights, Jun 2025 to May 2026).
- Departs inside SEA's trouble window: 54% of its 68 ground stops and delay programs started between 4 PM and 10 PM.
Strong track record · 343 flights
Find Alaska 538 fares Opens this date on Aviasales
Airlines on this route
Season-adjusted chance of operating and arriving on time.
- United Airlines79%
1,539 flights · 80% on time as flown · 0.9% cancel
- Delta Air Lines76%
898 flights · 77% on time as flown · 1.0% cancel
- Alaska Airlines72%
1,798 flights · 72% on time as flown · 0.9% cancel
- American Airlines69%
1,320 flights · 71% on time as flown · 1.9% cancel
On time by departure time
All airlines, scheduled local departure, Jun 2025 to May 2026.
- Before 9 AM85%
1,426 flights · avg delay 12 min
- 9 AM to noon70%
1,173 flights · avg delay 20 min
- Noon to 3 PM61%
838 flights · avg delay 25 min
- 3 to 6 PM75%
1,156 flights · avg delay 22 min
- After 9 PM78%
907 flights · avg delay 16 min
Best day: Wednesday (81%). Worst: Monday (75%).
Smarter routing
Nearby airports that run more on time
SEA → MDW 80% chance on time
Seattle–Tacoma International Airport to Chicago Midway International Airport · 673 flights a year · 15 mi from your airports · yours: 74%
On time by month
All airlines, Jun 2023 to May 2026. Several years per month, so one stormy season doesn't define a month. Travel-month estimates use this seasonal pattern.
What delays this route
- Airline (crew, maintenance, boarding)33%
- Late-arriving aircraft33%
- Air traffic control and airport volume31%
- Severe weather3%
Share of delay minutes by the cause airlines report to the US DOT.
Historical odds, not a guarantee. Built from the US DOT Bureau of Transportation Statistics on-time reports (Jun 2025 to May 2026), FAA ground stop and delay program advisories, and 20 years of airport weather observations. Covers US airlines that report to the DOT; schedules are flights operated recently, so confirm times when you book. ATIS Alerts is not affiliated with any airline. Fares are what Aviasales travelers saw in recent searches (USD, one way, 1 adult), not live quotes; the partner site shows the current price. Fare links go to our travel partner and may earn us a commission at no cost to you. Affiliate disclosure
SEA to ORD questions
- What time of day is best to fly SEA to ORD?
- Before 9 AM: 85% of flights arrived on time, against 61% for departures noon to 3 PM. Later flights inherit delays from earlier ones, so the first departures of the day usually run best.
- Which airline is most on time from SEA to ORD?
- United, with a season-adjusted 79% chance of operating and arriving on time over 1,539 flights. The adjustment compares each airline with what the route did in the months it flew, so a carrier that skipped a stormy month gets no free credit.
- What is the worst month for delays on SEA to ORD?
- August (70% on time); the best was February (86%), averaged over Jun 2023 to May 2026.
- Is this a prediction for my flight?
- No. These are historical odds from the US DOT on-time reports, FAA advisories and airport weather records. Check your flight status and the FAA delay board on the day you fly.
More routes from SEA
- ORD to SEA (return)
- SEA to LAX 83%
- SEA to PHX 79%
- SEA to SFO 69%
- SEA to ANC 74%
- SEA to DEN 77%
- SEA to LAS 77%
- SEA to GEG 81%
- SEA to DFW 77%
- SEA to PDX 82%
- SEA to SAN 78%
- SEA to SMF 81%
- SEA to SJC 82%
Live status: FAA delays and ground stops