$39 Cheap United flights St. Louis (STL) to Chicago (ORD)

Landing cheap one-way United Airlines flights from STL to ORD from $39 on Expedia is easy — just filter by “Price (lowest to highest).” Alternatively, check out our affordable return fares from $77 for your next break.**These prices were available on Expedia within the past 7 days, for flights departing within the next year. Prices and availability are subject to change. Additional terms apply.

January is one of the cheapest months to jet off to Chicago with United Airlines. You could also find great prices on one-way and return tickets in February.

To find cheap United Airlines fares from Lambert-St. Louis Intl. Airport (STL) to O’Hare Intl. Airport (ORD), start searching one to three months before your intended departure. Reserving domestic flights 34 to 86 days in advance could save you 25% compared to booking just 6 to 12 days ahead. The day you book can also affect the overall price. Sunday is usually the most affordable, while Monday is often the most expensive for domestic flights. You can save 6% on average by booking your trip on a Sunday.**Ideal booking window recommendation is based on average round-trip ticket prices for January through November for 2024. Best day of the week to book recommendation is based on average round-trip ticket prices for January through October 2024. All data sourced from ARC’s global airline sales database.

Easily travel from Lambert-St. Louis Intl. Airport (STL) to O’Hare Intl. Airport (ORD) on any of United Airlines’s 49 weekly direct flights. Make use of our “Nonstop” and “Airline” filters to find the United Airlines flight that’ll land at ORD at a time that suits you.

It takes approximately 1h 32m to fly nonstop from Lambert-St. Louis Intl. Airport (STL) to O’Hare Intl. Airport (ORD) with United Airlines.

If you’re looking for flexibility, Thursday offers the most choice for United Airlines flights from Lambert-St. Louis Intl. Airport (STL) to O’Hare Intl. Airport (ORD). You can pick from 7 different departures.

The earliest United Airlines flight from STL to ORD departs at 6:30AM UTC-6, arriving at 8:05AM UTC-6. If you prefer to set off later, the last United Airlines flight leaves STL at 5:30PM UTC-6 and touches down at ORD at 6:55PM UTC-6. Flying before midday is often a smart choice as morning flights are least likely to experience cancellations.**Most reliable time of the day recommendation is based on January through August 2024 flight status data sourced from OAG’s global flight data platform.

O’Hare Intl. Airport (ORD) is the main hub for United Airlines flights from Lambert-St. Louis Intl. Airport (STL) to Chicago. But this airline also travels to Midway Intl. Airport (MDW). Make sure you tick Expedia’s “All Airports” option for your destination to see all available choices for your getaway to Chicago.

Fly from STL to ORD with United Airlines and look forward to a range of benefits including a rewarding loyalty program. When booking through Expedia as a United Mileage Plus and One Key™ member, you can also earn OneKeyCash™* to spend on select future travel purchases.*OneKeyCash™ disclaimer - OneKeyCash™ is not redeemable for cash and can only be used on Expedia, Hotels.com and Vrbo.

United Airlines usually flies Canadair (Bombardier) Regional Jet 550 planes for flights from Lambert-St. Louis Intl. Airport (STL) to O’Hare Intl. Airport (ORD). This airline also operates the Boeing 737 MAX 8 on this route. Keep in mind that aircraft type can change depending on operational reasons, so the plane you board could be different on the day you travel.

Depending on the type of fare you purchased, a fee generally applies if you modify or cancel your booking more than 24 hours after it has been confirmed. To find flexible plane tickets, select our “Changes included” and “No cancel fee” boxes while looking for flights. To learn more about canceling or modifying your reservation, go to “Trips,” select your flight and click on “Manage Booking.”