Routes › St. Louis (STL) › STL to ORD
Route · 12 months to July 2026
St. Louis to Chicago: on-time record
St Louis Lambert International to Chicago O'Hare International
BTS: A flight is counted as on time if it arrived less than 15 minutes after its scheduled time. Only carriers with at least 0.5 percent of domestic scheduled passenger revenue report. Data through July 2026; this is a monthly history, not live flight status.
In the 12 months to July 2026, reporting carriers scheduled 3,090 flights from St. Louis (STL) to Chicago (ORD), a distance of 258 miles. 69.9% of them arrived within 15 minutes of schedule.
That is 6.1 points below the national on-time share of 76.0% for the same period and 6.9 points below the 76.8% recorded for all departures from STL. Flights that did arrive were 19.0 min late on average, and 3.6% of scheduled flights were cancelled (national: 1.8%).
5 reporting carriers flew the route at least 60 times. American Airlines had the highest on-time share at 79.1% of 502 flights; SkyWest Airlines had the lowest at 60.5% of 811.
By scheduled departure hour (local time at STL), flights leaving from 6 am to 7 am had the highest on-time share, 83.8%; those leaving from 7 pm to 8 pm had the lowest, 51.4%.
The on-time share is down 5.1 points on the previous 12 months (75.0%); cancellations moved from 1.2% to 3.6%.
Of the delay minutes that carriers assigned to a BTS cause category on this route, national aviation system 32%, late-arriving aircraft 30% and air carrier 27%.
- On time 69.9%
- Arrived 15+ minutes late 26.3%
- Cancelled 3.6%
- Diverted 0.2%
Airlines on the route compared
| Reporting carrier | Flights | Share | On time | Avg arrival delay | Cancelled |
|---|---|---|---|---|---|
| OO SkyWest Airlines | 811 | 26% | 60.5% | 32.7 min | 5.1% |
| MQ Envoy Air | 783 | 25% | 73.2% | 14.2 min | 2.9% |
| UA United Airlines | 557 | 18% | 69.8% | 18.7 min | 2.2% |
| AA American Airlines | 502 | 16% | 79.1% | 14.5 min | 2.6% |
| YX Republic Airline | 437 | 14% | 71.2% | 8.2 min | 4.8% |
Carriers with at least 24 flights in the 12 months to July 2026. The on-time pill is green when a carrier is at or above the route's overall share. Regional carriers operate flights sold under larger airlines' brands; BTS lists the carrier that operated the flight.
Compared with the airports and the nation
| Measure | STL to ORD | All departures from STL | All arrivals at ORD | All reported flights |
|---|---|---|---|---|
| Arrived on time | 69.9% | 76.8% | 71.2% | 76.0% |
| Arrived 15+ minutes late | 26.3% | 21.7% | 25.4% | 21.9% |
| Cancelled | 3.6% | 1.3% | 2.9% | 1.8% |
| Diverted | 0.2% | 0.3% | 0.5% | 0.3% |
| Average arrival delay | 19.0 min | 7.8 min | 15.4 min | 8.1 min |
| Delay minutes per 100 flights | 2,663 | 1,596 | 2,373 | 1,684 |
| Scheduled flights | 3,090 | 63,318 | 359,867 | 7,043,858 |
12 months to July 2026. Delay minutes count late arrivals only (an early arrival is zero), so the per-100-flights row is a normalised total rather than an average of early and late.
The return direction, ORD to STL, recorded 69.8% on time across 3,090 flights in the same period.
Month by month
Year on year: on time 69.9% against 75.0% (−5.1 pts), cancelled 3.6% against 1.2%, flights 3,090 against 2,776.
By scheduled departure hour
Delay causes
Seasonality
| Calendar month | Flights | On time | Cancelled | Avg arrival delay | Years in sample |
|---|---|---|---|---|---|
| Jan | 478 | 66.9% | 6.5% | 15.5 min | 3 |
| Feb | 515 | 82.5% | 1.0% | 5.3 min | 3 |
| Mar | 703 | 72.4% | 3.8% | 17.8 min | 3 |
| Apr | 817 | 75.0% | 2.3% | 14.1 min | 3 |
| May | 851 | 76.6% | 1.5% | 16.1 min | 3 |
| Jun | 833 | 69.5% | 2.2% | 22.8 min | 3 |
| Jul | 836 | 66.5% | 2.6% | 21.7 min | 3 |
| Aug | 748 | 72.7% | 1.9% | 14.4 min | 3 |
| Sep | 659 | 78.3% | 0.8% | 8.1 min | 3 |
| Oct | 686 | 79.2% | 0.0% | 9.0 min | 3 |
| Nov | 611 | 74.3% | 1.8% | 13.6 min | 3 |
| Dec | 565 | 73.6% | 1.4% | 15.8 min | 3 |
Each calendar month summed across the 36 months on file, so most rows combine three years. The pill compares the month with the route's own 12-month share.
Other routes from St. Louis (STL)
| Route | Cities | Flights | On time | Avg arrival delay | Cancelled |
|---|---|---|---|---|---|
| STL–ATL | St. Louis to Atlanta | 3,684 | 83.1% | -0.3 min | 1.7% |
| STL–DEN | St. Louis to Denver | 3,676 | 75.1% | 10.4 min | 0.3% |
| STL–LGA | St. Louis to New York | 2,624 | 71.6% | 8.9 min | 3.6% |
| STL–MCO | St. Louis to Orlando | 2,520 | 76.9% | 6.6 min | 0.9% |
| STL–DCA | St. Louis to Washington | 2,416 | 70.9% | 12.3 min | 2.6% |
| STL–DFW | St. Louis to Dallas/Fort Worth | 2,381 | 72.4% | 19.0 min | 3.3% |
| STL–PHX | St. Louis to Phoenix | 2,315 | 74.2% | 13.1 min | 0.5% |
| STL–LAS | St. Louis to Las Vegas | 2,094 | 75.2% | 8.5 min | 0.6% |
All 65 routes and the airport record for STL · airport record for ORD
Questions and answers
How often are flights from St. Louis to Chicago on time?
69.9% of the 3,090 flights scheduled from STL to ORD in the 12 months to July 2026 arrived less than 15 minutes after their scheduled time. The national share for the same period was 76.0%. Cancelled and diverted flights count as not on time.
Which airline has the highest on-time share from STL to ORD?
Among reporting carriers with at least 60 flights on the route, American Airlines had the highest on-time share (79.1%), followed by Envoy Air (73.2%) and Republic Airline (71.2%). Differences of a point or two on a few hundred flights are small.
What causes delays between St. Louis and Chicago?
For flights that arrived 15 or more minutes late, carriers attributed the delay minutes as follows: national aviation system 32%, late-arriving aircraft 30%, air carrier 27%, extreme weather 11%, security 0%. The categories are the carriers' own reports to BTS; weather that slows the wider system is usually recorded under the National Aviation System rather than extreme weather.
What time of day has the highest on-time share from STL?
Flights scheduled to leave STL from 6 am to 7 am arrived on time 83.8% of the time, the highest of any hour with enough flights to compare. The lowest was 7 pm to 8 pm at 51.4%. Delays tend to build through the day as late aircraft carry over to later flights.
Is it getting better?
The on-time share for the 12 months to July 2026 was 69.9%, down 5.1 points on the previous 12 months (75.0%). The monthly chart on this page shows each of the last 36 months. Across those months, February had the highest on-time share (82.5%) and July the lowest (66.5%).
Where does this data come from?
Every figure is computed from the Bureau of Transportation Statistics Reporting Carrier On-Time Performance files, which list each scheduled domestic flight by the carriers required to report. This page covers August 2023 to July 2026. It shows totals and averages only; it is not a live flight-status service.
Provenance
Source: Bureau of Transportation Statistics, Reporting Carrier On-Time Performance (1987 to present), monthly files August 2023 to July 2026, a US government work in the public domain. Figures are totals and averages over all scheduled flights by reporting carriers on the route; no individual flight or aircraft is identified. Times are local to the departure airport. The load factor and passenger counts from the BTS T-100 series are not included in this edition. See the methodology; report processing errors through corrections.