Route · MDW → SEA · 2020–2025 BTS data
Chicago to Seattle
The MDW–SEA corridor (Chicago, IL → Seattle, WA) runs behind the national average, served by 1 carrier across roughly 1,733 miles.
Data updated 2026-06-13
- 73.3%
- On-time
- -5.7 pts
- vs US avg
- 51 min
- Delay when late
- 3,110
- Flights
Cancelled
0.4%
Best Month
Sep 2025 79%
Worst Month
Jun 2024 55%
Distance
1,733 mi
Carriers
1
Monthly Performance
Recent 24 months of route data.
| Period | Flights | Delayed | Cancelled | Diverted | Carriers |
|---|---|---|---|---|---|
| Dec 2025 | 31 | 14 | 0 | 1 | WN |
| Nov 2025 | 30 | 11 | 1 | 0 | WN |
| Oct 2025 | 33 | 6 | 0 | 0 | WN |
| Sep 2025 | 86 | 18 | 0 | 0 | WN |
| Aug 2025 | 88 | 30 | 0 | 1 | WN |
| Jul 2025 | 88 | 36 | 1 | 1 | WN |
| Jun 2025 | 78 | 33 | 0 | 1 | WN |
| May 2025 | 31 | 8 | 0 | 1 | WN |
| Apr 2025 | 30 | 3 | 0 | 0 | WN |
| Mar 2025 | 31 | 12 | 0 | 0 | WN |
| Jan 2025 | 31 | 8 | 0 | 0 | WN |
| Dec 2024 | 31 | 8 | 0 | 0 | WN |
| Nov 2024 | 30 | 4 | 0 | 0 | WN |
| Oct 2024 | 35 | 10 | 0 | 0 | WN |
| Sep 2024 | 85 | 24 | 0 | 1 | WN |
| Aug 2024 | 88 | 39 | 0 | 1 | WN |
| Jul 2024 | 88 | 28 | 2 | 0 | WN |
| Jun 2024 | 80 | 36 | 1 | 4 | WN |
| May 2024 | 31 | 11 | 0 | 2 | WN |
| Apr 2024 | 30 | 7 | 0 | 0 | WN |
| Mar 2024 | 31 | 10 | 0 | 0 | WN |
| Jan 2024 | 31 | 11 | 0 | 0 | WN |
| Dec 2023 | 31 | 3 | 0 | 0 | WN |
| Nov 2023 | 32 | 3 | 0 | 0 | WN |
Cancellation Rate
0.4%
5 of 1,180 flights
Diversion Rate
1.1%
13 of 1,180 flights
Explore origin & destination
On-time and delay data for the airports this route connects.
MDW - Chicago
Full on-time, delay-cause, and seasonal performance for Chicago, IL.
Origin airport →SEA - Seattle
Full on-time, delay-cause, and seasonal performance for Seattle, WA.
Destination airport →Compare the two airports
See MDW and SEA side by side on delays, cancellations, and reliability.
Open comparison tool →Similar routes
Other BTS-tracked routes with comparable performance or trip length to MDW–SEA.
Routes with a similar on-time rate
What the Data Says About MDW to SEA
On-time performance on the MDW to SEA pairing (Chicago to Seattle) trails a chunk of the network: 73.3% of 3,110 tracked flights arrived on schedule, with a 51.3-minute average delay on the ones that ran late. The route spans about 1,733 miles across 1 carrier. Cancellations over the trailing 24 months hit 0.4% (5 of 1,180 flights), with 1.1% diverted.
The monthly split is wide on this route: Sep 2025 posted the strongest performance at 79% on-time, while Jun 2024 came in at just 55% - a 24-point swing worth factoring into travel timing.
Frequently Asked Questions
How often are flights delayed from MDW to SEA? ▼
What is the cancellation rate for MDW to SEA? ▼
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Flight Guides
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Data source
Data Source: Bureau of Transportation Statistics (BTS), On-Time Performance Data. Statistics reflect cumulative performance across all available reporting periods.
Read our methodology - how this data is sourced, computed, and verified.
Every figure on PlainFlights is rendered directly from BTS On-Time Performance data, no number is typed in by an editor. This page aggregates this specific route's on-time performance and monthly trend, live from the dataset. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error.