Route · STL → ORD · 2020–2025 BTS data
St. Louis to Chicago
According to PlainFlights' route traffic ranking (BTS On-Time Performance total flights), STL to ORD (St. Louis to Chicago) ranks #735 of 4927 tracked domestic routes by total flights (most flights = #1).
Data updated 2026-06-13
- 80.8%
- On-time
- +1.8 pts
- vs US avg
- 99 min
- Delay when late
- 13,549
- Flights
- #735 of 4927
- Corpus placement
Cancelled
1.6%
Best Month
Mar 2024 85%
Worst Month
Jul 2025 62%
Distance
258 mi
Carriers
37
Monthly Performance
Recent 24 months of route data.
| Period | Flights | Delayed | Cancelled | Diverted | Carriers |
|---|---|---|---|---|---|
| Dec 2025 | 240 | 87 | 7 | 0 | YX,AA,MQ,UA,OO |
| Nov 2025 | 241 | 73 | 11 | 1 | OO,UA,MQ,AA,YX |
| Oct 2025 | 274 | 81 | 0 | 0 | AA,OO,UA,YX,MQ |
| Sep 2025 | 239 | 45 | 2 | 0 | MQ,UA,OO,YX,AA |
| Aug 2025 | 255 | 76 | 10 | 0 | AA,OO,YX,MQ,UA |
| Jul 2025 | 289 | 110 | 5 | 0 | AA,OO,UA,YX,MQ |
| Jun 2025 | 294 | 85 | 3 | 0 | AA,OO,UA,YX,MQ |
| May 2025 | 284 | 59 | 3 | 0 | AA,OO,UA,YX,MQ |
| Apr 2025 | 264 | 56 | 4 | 0 | MQ,OO,UA,YX,AA |
| Mar 2025 | 228 | 50 | 5 | 1 | AA,YX,OO,UA,MQ |
| Feb 2025 | 164 | 29 | 3 | 0 | AA,OO,UA,YX,MQ |
| Jan 2025 | 150 | 31 | 8 | 0 | AA,OO,UA,YX,MQ |
| Dec 2024 | 175 | 34 | 1 | 0 | AA,MQ,OO,UA,YX |
| Nov 2024 | 209 | 50 | 0 | 0 | OO,YX,UA,MQ,AA |
| Oct 2024 | 247 | 37 | 0 | 0 | UA,MQ,OO,YX,AA |
| Sep 2024 | 221 | 44 | 1 | 0 | YX,OO,UA,AA,MQ |
| Aug 2024 | 251 | 74 | 1 | 0 | AA,MQ,OO,UA |
| Jul 2024 | 238 | 80 | 1 | 0 | AA,MQ,OO,UA,YX |
| Jun 2024 | 235 | 64 | 2 | 0 | AA,MQ,OO,UA,YX |
| May 2024 | 245 | 64 | 4 | 1 | AA,MQ,YX,OO,UA |
| Apr 2024 | 259 | 49 | 0 | 0 | AA,MQ,UA,YX |
| Mar 2024 | 204 | 30 | 0 | 0 | AA,MQ,YX,OO,UA |
| Feb 2024 | 166 | 26 | 1 | 0 | AA,MQ,OO,UA,YX |
| Jan 2024 | 172 | 53 | 16 | 0 | AA,MQ,YX,OO,UA |
STL–ORD seasonal on-time pattern
Best: March (85.6%) · weakest: July (74.2%)
Strongest calendar month
March
85.6% on-time · ~189 flights/mo
Busiest calendar month
August
~218 flights/mo avg
Weakest calendar month
July
74.2% on-time · ~213 flights/mo
Cancellation Rate
1.6%
88 of 5,544 flights
Diversion Rate
0.1%
3 of 5,544 flights
Explore origin & destination
On-time and delay data for the airports this route connects.
STL - St. Louis
Full on-time, delay-cause, and seasonal performance for St. Louis, MO.
STL on-time profileORD - Chicago
Full on-time, delay-cause, and seasonal performance for Chicago, IL.
ORD on-time profileCompare the two airports
See STL and ORD side by side on delays, cancellations, and reliability.
Compare STL vs ORDOrigin-hub reliability standing
Mid-pack among STL departures
From STL, this corridor sits with 45 other 75–85% on-time routes out of 51 tracked departures, not the hub's reliability leaders (5 at ≥85%) and not the softest ( 1 below 75%). Destination: Chicago · fleet on-time rank #2834 of 4927.
Similar routes
Other BTS-tracked routes with comparable performance or trip length to STL–ORD.
Routes with a similar on-time rate
What the Data Says About STL to ORD
13,549 tracked flights put the STL to ORD pairing (St. Louis to Chicago) at a 80.8% on-time rate, squarely in line with the wider network. Delays that do occur run 99.1 minutes on average. Across the 258-mile route and its 37 carriers, the trailing 24 months show 1.6% cancelled and 0.1% diverted (5,544 flights sampled).
The monthly split is wide on this route: Mar 2024 posted the strongest performance at 85% on-time, while Jul 2025 came in at just 62% - a 23-point swing worth factoring into travel timing.
On the multi-year calendar, STL–ORD peaks in March at 85.6% on-time while August carries the heaviest traffic (~218 flights per month) ; the softest month is July at 74.2%, a 11.4-point swing that repeats because the corridor's weather and holiday mix stays stable year to year.
Frequently Asked Questions
Where does STL to ORD rank among US routes by traffic? ▼
How often are flights delayed from STL to ORD? ▼
What is the cancellation rate for STL to ORD? ▼
How far is the flight from STL to ORD? ▼
When is the best time to fly from STL to ORD? ▼
Airports on this route
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.
Using STL–ORD data
STL–ORD is mid-pack at 80.8% on-time; month and carrier mix move more than the corridor headline.
- Compare STL and ORD airport profiles: delay causes and top routes differ even on the same corridor. STL airport
- If your dates flex, March (85.6% on-time) beats July (74.2%) on this corridor. Seasonal chart
- 4 other routes post a similar 80.8% on-time rate; compare before you commit to this pairing. Similar routes
On-time rate reflects the BTS historical average across all reporting carriers on this origin–destination pair, not any single flight or booking recommendation.
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.