Route profile
SEA→ORD
Flight reliability, delays and best times to fly from Seattle to Chicago, 1,721 miles.
Right now
Aviation weather is not currently a factor.
Aviation weather is not currently a factor.
Route reliability
July 2023 – July 2026
Better than 52% of comparable major US routes (4,598 compared)
Calculated from 16,300 flights. How this is calculated
SEA → ORD arrives on time 77.3% of the time; the return trip, ORD → SEA, arrives on time 74.0% of the time, a 3.4-point gap between the two directions of the same city pair.
SEA → ORD spends 37.8 minutes on the ground on a 1,721-mile trip: 20.8 minutes from pushback to wheels-up at SEA and 17.1 minutes from touchdown to gate at ORD.
Source: US DOT Bureau of Transportation Statistics · Data covering July 2023 – July 2026
Why SEA → ORD flights are cancelled
July 2023 – July 2026
SEA → ORD cancelled 155 of 16,300 scheduled flights — about 1 in every 105. The reason filed most often was extreme weather, 47.1% of the cancellations coded on this route — about 1 in every 223 scheduled flights.
Share of cancellations
Of 155 cancelled departures carrying a reason code.
What each reason means
Conditions the carrier judged severe enough to stop the flight: a blizzard, a hurricane, a line of thunderstorms.
73 cancellations, 47.1% of the total.
Crew, maintenance, aircraft cleaning, baggage or fueling: what BTS counts as within the carrier’s own control.
64 cancellations, 41.3% of the total.
Airport capacity, air traffic control flow programs, heavy traffic and ordinary bad weather. A system decision, not the airline’s.
18 cancellations, 11.6% of the total.
A terminal evacuation, a security breach, screening equipment failure, or screening queues over 29 minutes.
0 cancellations, 0.0% of the total.
Reason codes are the operating airline’s own filing with US DOT, not an independent finding of fault. Ordinary bad weather is filed under air traffic, so weather’s full share is larger than its bar.
155 coded cancellations were recorded on SEA → ORD; the section appears from 50.
When it goes wrong
July 2023 – July 2026
42 min late
against a median of 5 min early
Percentiles over 16,300 operations; cancelled and diverted flights are counted separately.
Will your connection be tight enough?
Layovers at ORD after arriving from SEA.
| Connection time | Chance of missing | Reads as |
|---|---|---|
| 30 min | 41% | Likely to miss |
| 45 min | 22% | High risk |
| 60 min | 14% | Some risk |
| 90 min | 6.7% | Some risk |
| 120 min | 4.0% | Low risk |
This is one leg of a connection. Gate changes and the next flight's own schedule matter too. And a connection can fail before delay is even the question — this route cancels 0.95% of the time and diverts 0.62% of the time, which a late arrival never shows up in.
Chance of missing is the share of 16,044 arrivals on this route that landed later than the connection time less 30 minutes to reach the next gate.
The worst tenth of arrivals on this route land at least 42 minutes late (90th-percentile gate arrival delay), over 16,300 operations.
Any other layover length: connection checker.
Best time to fly
SEA → ORD flights departing 5–9 AM arrived on time 85.6% of the time, against 63.5% for 12–3 PM departures, a gap of 22.1 percentage points.
By day and hour
On-time arrival rate for each weekday and scheduled departure hour, in local time at the departure airport (SEA).
Hour of departure matters more than day of the week: hourly averages sit a typical 8.5 points from the route-wide rate, weekday averages 2.5 points.
| Hour | Monday | Tuesday | Wednesday | Thursday | Friday | Saturday | Sunday |
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On-time rate, % · stronger color, fewer on time
- 50–59
- 60–69
- 70–79
- 80–89
- 90–99
- Fewer than 120 flights, not scored
Source: FlyerIntel analysis of US DOT BTS data · July 2023 – July 2026 · On time is arrival within 15 minutes of schedule. Cells round to whole percentages; the table shows one decimal.
No slot is named best or worst: too few reach 500 flights.
View as tableHide table
| Hour | Monday | Tuesday | Wednesday | Thursday | Friday | Saturday | Sunday |
|---|---|---|---|---|---|---|---|
| 12 AM–1 AM | 117 flights, too few to score | 105 flights, too few to score | 90 flights, too few to score | 110 flights, too few to score | 77.7% on time121 flights | 111 flights, too few to score | 106 flights, too few to score |
| 1 AM–2 AM | 1 flight, too few to score | 0 flights, too few to score | 0 flights, too few to score | 0 flights, too few to score | 0 flights, too few to score | 0 flights, too few to score | 0 flights, too few to score |
| 2 AM–3 AM | 0 flights, too few to score | 0 flights, too few to score | 0 flights, too few to score | 0 flights, too few to score | 0 flights, too few to score | 0 flights, too few to score | 0 flights, too few to score |
| 3 AM–4 AM | 0 flights, too few to score | 0 flights, too few to score | 0 flights, too few to score | 0 flights, too few to score | 0 flights, too few to score | 0 flights, too few to score | 0 flights, too few to score |
| 4 AM–5 AM | 0 flights, too few to score | 0 flights, too few to score | 0 flights, too few to score | 0 flights, too few to score | 0 flights, too few to score | 0 flights, too few to score | 0 flights, too few to score |
| 5 AM–6 AM | 19 flights, too few to score | 19 flights, too few to score | 15 flights, too few to score | 21 flights, too few to score | 20 flights, too few to score | 16 flights, too few to score | 20 flights, too few to score |
| 6 AM–7 AM | 91.2% on time188 flights | 88.8% on time172 flights | 93.5% on time170 flights | 92.5% on time187 flights | 91.5% on time188 flights | 94.3% on time176 flights | 90.4% on time178 flights |
| 7 AM–8 AM | 83.5% on time311 flights | 87.5% on time317 flights | 87.5% on time316 flights | 85.1% on time310 flights | 82.4% on time309 flights | 89.2% on time253 flights | 80.4% on time292 flights |
| 8 AM–9 AM | 72.6% on time120 flights | 104 flights, too few to score | 102 flights, too few to score | 77.0% on time122 flights | 76.3% on time120 flights | 90 flights, too few to score | 101 flights, too few to score |
| 9 AM–10 AM | 7 flights, too few to score | 15 flights, too few to score | 16 flights, too few to score | 8 flights, too few to score | 5 flights, too few to score | 28 flights, too few to score | 14 flights, too few to score |
| 10 AM–11 AM | 73.5% on time308 flights | 79.9% on time293 flights | 71.2% on time295 flights | 72.4% on time310 flights | 73.6% on time314 flights | 79.9% on time276 flights | 69.8% on time300 flights |
| 11 AM–12 PM | 70.9% on time184 flights | 83.8% on time174 flights | 73.9% on time176 flights | 78.6% on time175 flights | 74.7% on time180 flights | 74.5% on time137 flights | 71.8% on time192 flights |
| 12 PM–1 PM | 99 flights, too few to score | 79 flights, too few to score | 79 flights, too few to score | 96 flights, too few to score | 95 flights, too few to score | 81 flights, too few to score | 95 flights, too few to score |
| 1 PM–2 PM | 63.2% on time210 flights | 67.5% on time195 flights | 65.8% on time200 flights | 56.4% on time218 flights | 52.8% on time218 flights | 57.1% on time151 flights | 58.7% on time214 flights |
| 2 PM–3 PM | 62.7% on time120 flights | 101 flights, too few to score | 100 flights, too few to score | 108 flights, too few to score | 108 flights, too few to score | 70 flights, too few to score | 112 flights, too few to score |
| 3 PM–4 PM | 46 flights, too few to score | 50 flights, too few to score | 51 flights, too few to score | 49 flights, too few to score | 48 flights, too few to score | 50 flights, too few to score | 48 flights, too few to score |
| 4 PM–5 PM | 28 flights, too few to score | 29 flights, too few to score | 30 flights, too few to score | 33 flights, too few to score | 24 flights, too few to score | 18 flights, too few to score | 29 flights, too few to score |
| 5 PM–6 PM | 79.3% on time249 flights | 81.2% on time243 flights | 83.5% on time238 flights | 75.8% on time257 flights | 81.7% on time257 flights | 81.2% on time229 flights | 78.9% on time233 flights |
| 6 PM–7 PM | 71.4% on time129 flights | 82.5% on time127 flights | 84.4% on time122 flights | 79.3% on time124 flights | 77.5% on time122 flights | 96 flights, too few to score | 119 flights, too few to score |
| 7 PM–8 PM | 0 flights, too few to score | 0 flights, too few to score | 0 flights, too few to score | 0 flights, too few to score | 0 flights, too few to score | 0 flights, too few to score | 2 flights, too few to score |
| 8 PM–9 PM | 0 flights, too few to score | 0 flights, too few to score | 0 flights, too few to score | 0 flights, too few to score | 0 flights, too few to score | 0 flights, too few to score | 0 flights, too few to score |
| 9 PM–10 PM | 0 flights, too few to score | 0 flights, too few to score | 0 flights, too few to score | 0 flights, too few to score | 0 flights, too few to score | 0 flights, too few to score | 0 flights, too few to score |
| 10 PM–11 PM | 54 flights, too few to score | 41 flights, too few to score | 47 flights, too few to score | 53 flights, too few to score | 56 flights, too few to score | 51 flights, too few to score | 54 flights, too few to score |
| 11 PM–12 AM | 80.7% on time246 flights | 85.6% on time223 flights | 85.8% on time231 flights | 80.4% on time255 flights | 80.0% on time255 flights | 82.5% on time218 flights | 79.3% on time263 flights |
By departure window
By departure hour
- 12 AM: 81.0% on time from 760 flights
- 1 AM to 4 AM: too few flights to score
- 5 AM: 87.7% on time from 130 flights
- 6 AM: 91.7% on time from 1,259 flights
- 7 AM: 85.0% on time from 2,108 flights
- 8 AM: 76.6% on time from 759 flights
- 9 AM: too few flights to score
- 10 AM: 74.3% on time from 2,096 flights
- 11 AM: 75.4% on time from 1,218 flights
- 12 PM: 61.1% on time from 624 flights
- 1 PM: 60.2% on time from 1,406 flights
- 2 PM: 72.0% on time from 719 flights
- 3 PM: 63.3% on time from 342 flights
- 4 PM: 75.0% on time from 191 flights
- 5 PM: 80.2% on time from 1,706 flights
- 6 PM: 79.6% on time from 839 flights
- 7 PM to 9 PM: too few flights to score
- 10 PM: 76.3% on time from 356 flights
- 11 PM: 81.9% on time from 1,691 flights
Why SEA → ORD runs late
July 2023 – July 2026
crew, maintenance, boarding and fueling, all within the carrier’s control
the inbound aircraft was late, so this flight started late
airspace and airport capacity, including weather-driven flow control
weather severe enough to stop this flight specifically
screening or terminal security incidents
Share of the delay minutes US DOT attributed to each cause for SEA → ORD. Only delays of 15 minutes or more are attributed.
How this route holds up in bad weather
July 2023 – July 2026
The harder-hit end is ORD, where the flight lands. Its figure counts departures from ORD, so it says more about how that airport copes than about this route. Bad weather cancels 5.5 times the normal rate at ORD against 1.9 times at SEA. Cancelled in bad weather against normal hours: SEA 1.5% against 0.8%, ORD 6.5% against 1.2%. Flights that did leave ORD in bad weather arrived on time 55.7% of the time, against 77.1% in normal hours.
Bad weather and normal hours at the airports
Scheduled departures, July 2023 – July 2026| Departures from | SEA | ORD |
|---|---|---|
| Cancelled in bad weather | 1.5% | 6.5% |
| Cancelled in normal hours | 0.8% | 1.2% |
| Arrived on time, bad weather | 75.4% | 55.7% |
| Arrived on time, normal hours | 79.3% | 77.1% |
| Departures in bad weather | 43,416 | 104,455 |
Of the carriers on this route, United Airlines (0.8% cancelled against 1.5% for the other carriers at SEA) cancelled the fewest departures from SEA in bad weather and Alaska Airlines (1.8% cancelled against 1.2% for the other carriers at SEA) the most.
This route’s airlines in bad weather at SEA
All departures from SEA| Airline | Bad-weather departures | Cancelled | Other carriers |
|---|---|---|---|
| United Airlines | 2,531 | 0.8%below the others | 1.5% |
| Delta Air Lines | 9,020 | 1.1%below the others | 1.6% |
| American Airlines | 1,665 | 1.0%about level | 1.5% |
| Alaska Airlines | 20,261 | 1.8%above the others | 1.2% |
These are airport figures, not route figures: every scheduled departure from SEA and ORD, to any destination, in hours the weather report called bad. The airline rows count each carrier’s departures from SEA on every route.
Weather source and limits. In full: SEA (airlines), ORD, What Weather Costs Each Airport, Who Cancels More When the Weather Turns, Airports That Change Places When Weather Turns.
Airlines on this route
Carriers with at least 200 flights, by the airline that operated each one.
| Carrier | Flights | On time | Cancelled | Median delay | Severe |
|---|---|---|---|---|---|
| Alaska Airlines | 5,678 | 74.1% | 0.77% | -2 min | 5.8% |
| United Airlines | 4,762 | 82.0% | 0.94% | -7 min | 6.0% |
| American Airlines | 3,030 | 74.5% | 1.49% | -6 min | 9.2% |
| Delta Air Lines | 2,830 | 79.0% | 0.74% | -4 min | 7.6% |
Alaska Airlines flew 34.8% of the 16,300 flights listed.
United Airlines arrived on time 7.9 percentage points more often than Alaska Airlines on this route.
Flights on this route
Flight numbers with at least 600 operations here and still on the schedule.
UA747 (11:59 PM) arrived on time 84.7% of the time, 24.2 points more often than AS410 (12:12 PM) at 60.5%.
Weekly and seasonal patterns
By day of week
Tuesday is historically the most reliable day and Sunday the least, a gap of 5.9 percentage points.
By month
- Jan: 75.1%
- Feb: 85.7%
- Mar: 83.5%
- Apr: 80.9%
- May: 76.3%
- Jun: 73.3%
- Jul: 70.5%
- Aug: 70.0%
- Sep: 79.1%
- Oct: 84.8%
- Nov: 82.8%
- Dec: 79.5%
August is historically the weakest month and February the strongest, a spread of 15.7 percentage points.
Reliability over time
July 2023 – July 2026
- July 2023: 78.3% from 550 flights
- August 2023: 78.5% from 563 flights
- September 2023: 78.9% from 494 flights
- October 2023: 87.7% from 432 flights
- November 2023: 87.1% from 363 flights
- December 2023: 84.7% from 334 flights
- January 2024: 73.1% from 272 flights
- February 2024: 84.2% from 248 flights
- March 2024: 86.1% from 312 flights
- April 2024: 83.4% from 398 flights
- May 2024: 66.2% from 466 flights
- June 2024: 76.8% from 522 flights
- July 2024: 68.5% from 575 flights
- August 2024: 70.9% from 551 flights
- September 2024: 78.7% from 483 flights
- October 2024: 86.2% from 435 flights
- November 2024: 86.8% from 357 flights
- December 2024: 84.4% from 366 flights
- January 2025: 78.7% from 283 flights
- February 2025: 79.5% from 259 flights
- March 2025: 85.0% from 331 flights
- April 2025: 79.7% from 426 flights
- May 2025: 79.7% from 536 flights
- June 2025: 70.8% from 571 flights
- July 2025: 65.2% from 623 flights
- August 2025: 60.9% from 599 flights
- September 2025: 79.7% from 509 flights
- October 2025: 81.1% from 496 flights
- November 2025: 74.7% from 390 flights
- December 2025: 70.1% from 382 flights
- January 2026: 73.3% from 301 flights
- February 2026: 92.3% from 300 flights
- March 2026: 79.8% from 357 flights
- April 2026: 79.7% from 465 flights
- May 2026: 81.3% from 562 flights
- June 2026: 72.5% from 582 flights
- July 2026: 70.7% from 607 flights
Over the most recent 12 months (2025-08 to 2026-07), on-time arrivals averaged 75.6% against 77.6% in the 12 months before — declining by 2.0 percentage points.
Data and methodology
Calculated by FlyerIntel from 16,300 SEA → ORD flight records from the US DOT Bureau of Transportation Statistics, covering July 2023 – July 2026. Late means 15 or more minutes past scheduled arrival; cancelled and diverted flights are left out of on-time rates.
Full methodology · Data sources · Report a problem
Related research: How Long a Layover Needs to Be · Two Airlines on One Route · Best Time of Day to Fly From Major US Airports
Analysis last recomputed