The cheapest times to fly from ORD to STL are

  • early August
  • August 20th to April 29th (except the week of October 1st)

based on data collected exclusively by Champion Traveler across tens of millions of flights. Among all the dates above, the very cheapest time to fly from ORD to STL is mid December. Prices can be as high as $197 for Saturday flights during early to mid August, or as low as $165 for Thursday flights around mid December.


When to Fly to St. Louis

Flying from Chicago, IL (ORD) to St. Louis, MO (STL) will usually cost between $165 to $170 per person if booking more than four weeks in advance. On average the very cheapest time to fly is mid December with an average ticket price of $165. Due to high demand the most expensive time to fly is early to mid August, with an average price of $174. Planning your trip to low-cost times can easily save you $9 on economy flights and even more on first-class flights. Generally, any price below $167 can be considered a good price for a round-trip ORD to STL flight.

See below for a graph of average weekly prices for the ORD to STL route. All prices are for round-trip tickets in USD.

ORD to STL Flight Prices

Compared to other flights, the ORD to STL flight is much cheaper than the average and costs much less than the average flight leaving from Chicago. The average price per mile (for a direct flight) is $0.4, which is a bit above average.


Flight Prices by Day of the Week

Thursday is usually the cheapest day to depart and return on this flight. Saturdays are the most expensive days to fly to St. Louis, and Sundays are the most expensive days to return to Chicago. Selecting flights on the least expensive days could save you up to $3 (2%) on this flight.

Departing prices are for round-trip flights returning on the day of departure. For example, a flight departing on Thursday and returning a week later will cost an average of $165. Return trip prices are from the STL to ORD flight, and often highlight the quality of our data in showing the same trend.

Departing Prices by Day

Departure Day Prices

Return Trip Prices by Day

Return Day Prices


Nonstop Flights and Layovers

Travelers looking to fly from ORD to STL can generally find a 0-layover flight. Because there is a direct flight option the real-world direct flight time of 1 hour 27 minutes may be realistic.


Alternative Nearby Airports

Champion Traveler tells you which airports are nearby and whether tickets might be cheaper alternative airports nearby. Sometimes it’s worth it to fly into a closer airport and then commute to your destination. Remember that there is a nonstop flight from ORD to STL while comparing.

Destination alternative #1: Decatur Airport (DEC) in Decatur, IL

  • 110 miles (177 km) away from STL
  • Usually 26.13% less expensive than STL
  • Nonstop flights available

See ORD to DEC flights

Destination alternative #2: Quincy Regional-Baldwin Field Airport (UIN) in Quincy, IL

  • 94 miles (151 km) away from STL
  • Usually 14.71% less expensive than STL
  • Nonstop flights available

See ORD to UIN flights


Flight Questions Answered

Still have questions about flying from ORD to STL? We’ve got answers.

Which airlines fly this route?

You can find 9 major airlines flying this route most often: Air Choice One, Alaska, American, Cape Air, Delta, Frontier, Qantas, Sun Country Airlines, United, and potentially more during busy seasons.

How far away is it from St Louis Lambert International Airport to Chicago O’Hare International Airport?

The distance between the two airports is roughly 258 miles or 415 kilometers.

How long does it take to fly from ORD to STL?

The real-world flight time for a nonstop ORD to STL flight is about 1 hour 27 minutes.

How many flights go between Chicago, IL and St. Louis, MO?

It depends on the day of the week and the date, but a typical day might have around 47 available flights from ORD to STL.


Airport Location Info


Departing Airport

Origination code ORD
Origination airport name Chicago O’Hare International Airport
City Chicago, IL
Country the United States
Latitude 42
Longitude -87.9

Return Airport

Destination code STL
Destination airport name St Louis Lambert International Airport
City St. Louis, MO
Country the United States
Latitude 38.7
Longitude -90.4


Late and Early Flight Data

Flights from ORD to STL tend to depart later than the average flight. According to our recently updated data, 35% of flights departed 5 or more minutes late, and 9% of flights left 5 or more minutes early. On average you can expect to leave STL heading for ORD about 20 minutes late. This does significantly impact arrival time, as the average landing time in St. Louis, MO is about 23 minutes late. The numbers below show a recent average of take-off times versus the scheduled departure flight:

  • American: 27 minutes late
  • SkyWest: 23 minutes late
  • United: 45 minutes late
  • Envoy: 8 minutes late
  • Republic: 4 minutes early
  • ExpressJet: 15 minutes late
  • Some airlines not reporting


Other Resources

Please note that while we’ve worked hard to analyzed tens of millions of flights to get you this data, we do not calculate current live prices or guarantee pricing. Please see our partners using the links above for current offers.