STL to ORD flight delays & on-time performance
Nonstop flights from St. Louis Lambert International Airport to Chicago O'Hare International Airport · 258 miles · Aug 2025 – Jul 2026
No FAA-reported ground stops or delays at STL or ORD right now. Individual flights can still be delayed by the airline; check with your airline for your flight.
Key facts
- Flights from St. Louis (STL) to Chicago (ORD) arrived on time 73% of the time in Aug 2025 – Jul 2026, worse than the 78% national average.
- 3.6% were cancelled, and 11% arrived an hour or more late.
- American Airlines was the most punctual airline here (81% on time); SkyWest Airlines was the least (64%).
- Departures scheduled around 6am did best (85% on time); around 7pm did worst (55%).
- Wednesday was the most reliable day to fly (77% on time) and Sunday the least (68%).
- The largest source of delay minutes was air traffic control & airport congestion (32%).
Which airline is most on time from STL to ORD?
Ranked by on-time arrival rate. Regional airlines fly under their partner's brand (e.g. SkyWest for Delta Connection or United Express).
| Airline | On time | Cancelled | Avg delay | 1 hr+ late | Flights |
|---|---|---|---|---|---|
| American Airlines | 81% | 2.6% | 26 min | 9.4% | 502 |
| Envoy AirRegional airline operating American Eagle flights. | 75% | 2.9% | 24 min | 9.1% | 783 |
| Republic AirwaysRegional airline operating flights for American Eagle, Delta Connection and United Express. | 75% | 4.8% | 20 min | 9.9% | 437 |
| United Airlines | 72% | 2.2% | 24 min | 8.8% | 557 |
| SkyWest AirlinesRegional airline operating flights for United Express, Delta Connection, American Eagle and Alaska. | 64% | 5.1% | 39 min | 17.7% | 811 |
Best time of day to fly
On-time arrival rate by scheduled departure hour (local time).
- 5am95%64 flights
- 6am85%320 flights
- 7am80%281 flights
- 8am78%208 flights
- 9am84%268 flights
- 10am71%51 flights
- 11am63%41 flights
- 12pm69%86 flights
- 1pm66%275 flights
- 2pm69%244 flights
- 3pm74%267 flights
- 4pm68%167 flights
- 5pm68%376 flights
- 6pm61%166 flights
- 7pm55%138 flights
- 8pm57%136 flights
Best day of the week
On-time arrival rate by day of departure.
- Monday72%7.0% cancelled
- Tuesday76%2.1% cancelled
- Wednesday77%2.5% cancelled
- Thursday72%2.2% cancelled
- Friday70%4.1% cancelled
- Saturday75%4.0% cancelled
- Sunday68%2.9% cancelled
On-time trend by month
Why flights are late
Share of delay minutes by cause, as reported by airlines to the DOT.
- Air traffic control & airport congestion32%
- Late-arriving aircraft30%
- Airline (crew, maintenance, cleaning, fueling)27%
- Extreme weather11%
- Security0%
Why flights are cancelled
Share of cancellations by reason.
- Extreme weather75%
- Air traffic control & airport congestion21%
- Airline (crew, maintenance, cleaning, fueling)4%
- Security0%
STL to ORD: common questions
- How often are STL to ORD flights on time?
- 73% of flights arrived less than 15 minutes late in Aug 2025 – Jul 2026, compared with 78% for all US flights.
- How often are flights from St. Louis to Chicago cancelled?
- 3.6% of scheduled flights were cancelled (110 of 3,090).
- How long are typical delays?
- Across all flights the average arrival delay was 28 min (early arrivals count as zero). Flights that were late arrived 97 min behind schedule on average, and 11.4% of flights were an hour or more late.
- How long is taxi time at STL?
- Flights on this route spent 17 min taxiing from the gate to takeoff on average.
Related routes
Return trip: ORD to STL — 72% on time
More flights from St. Louis
Data: U.S. DOT Bureau of Transportation Statistics, Aug 2025 – Jul 2026 (12 months). Latest month published by BTS: July 2026. Route: STL → ORD, nonstop flights by US airlines that report to the DOT. How we calculate this.