Cheap flights from St. Louis to Illinois from $62
This is the cheapest one-way flight price found by a momondo user in the last 72 hours by searching for a flight from St. Louis to Illinois departing on 5/30. Fares may change, and may not be available for all flights or travel dates. Click the price to refresh the search for this deal.
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Southern / Mokulele flights from St. Louis to Illinois
Our best Southern / Mokulele deals on St. Louis to Illinois flight tickets
Frontier flights from St. Louis to Illinois
Our best Frontier deals on St. Louis to Illinois flight tickets
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How to get the cheapest flight ticket from St. Louis to Illinois
Look no further. We've gone through all the searches for this route on momondo so you have the important information and insights to find the cheapest flight ticket for your trip
What is the cheapest month to fly to Illinois?
The cheapest month to fly to Illinois from St. Louis is in May. Flight prices, which tend to average around $187, are often lower during this time because this is during the off-season. If you aren’t able to travel to Illinois during the month of May, then flying in August is also cheap. Prices for this month can be found on momondo for an average of $190.
What is the cheapest day to depart on your flight to Illinois?
The cheapest day to depart from St. Louis to Illinois is on a Thursday when prices can be found for as low as $813. Flights from St. Louis to Illinois on a Tuesday will generally be more expensive and average around $1,041. Keep in mind that these prices on both days could fluctuate depending on the season and the demand.
What is the cheapest time of day to depart on your flight to Illinois?
Our most recent data shows that the best time of day to fly to Illinois is in the morning. Flights from St. Louis to Illinois during this time can be as low as $670. Flights at noon are often more expensive with an average ticket price of $1,303.
What is the cheapest Lambert-St Louis to Illinois flight route?
Fly from Lambert-St Louis to Chicago Midway for the best Lambert-St Louis - Illinois flight prices
How far in advance should I book a flight to Illinois?
You are more likely to see cheaper flights to Illinois from St. Louis when booking 4 weeks ahead of your departure date. In general, you can expect to find flights to Illinois for around $267 when searching 4 weeks out.However, flight prices might be lower outside of this timeframe. For example, people recently found flights to Illinois from St. Louis for as low as $196 on momondo.
What cabin class options are available on Lambert-St Louis to Illinois flights?
There are 4 cabin classes available to choose from on Lambert-St Louis to Illinois flights. Cabin price and availability will vary by airline so perform a search above to find the right deals for you.
What is the cheapest airline that flies from Lambert-St Louis to Illinois?
Southern / Mokulele, Frontier, and Southwest are the most popular carriers operating from Lambert-St Louis to Illinois
What airlines fly to Illinois?
American Airlines, United Airlines and Southwest are the top three most popular airlines that fly to Illinois from St. Louis according to our data. American Airlines is the first choice among our users, with 57% of people opting to fly with this airline when traveling to Illinois. Keep in mind that there are 5 different airlines that fly to Illinois on a routine basis, so you have a few additional options to choose from.
How many flights depart from St. Louis to Illinois on average per day?
62 flights are operational daily from St. Louis to Illinois as of May 2025. The most popular departure time for this route is 3:00PM, with 46% of flights per day taking off at noon.
How many flights depart from St. Louis to Illinois on average per week?
The number of flights available between St. Louis and Illinois is 439 per week as of May 2025. The most frequent departure day is Mon, with 18% of weekly flights leaving on this day.
Cheap St. Louis to Illinois flight deals and tips
Find info about flight duration, direct flights, and airports for your flight from St. Louis to Illinois
When did momondo last update prices for flights from Lambert-St Louis Airport to Illinois?
Prices for flights from Lambert-St Louis Airport to Illinois refresh daily.
How many operators does momondo search for flights from Lambert-St Louis Airport to Illinois?
There are 4 operators available for flights from Lambert-St Louis Airport to Illinois as of May 2025.
How old do you have to be to fly from Lambert-St Louis Airport to Illinois?
Although the minimum age for a child to fly alone is five, airlines that offer an unaccompanied minor (UMNR) service may have their own age limits, which could be impacted by factors such as flight length, timing, and layovers. It is recommended that you verify with the airline you are booking with for travel from Lambert-St Louis Airport to Illinois.
What documentation or ID do you need to fly to Illinois?
The travel and health documents you'll need for your trip to Illinois may differ based on your itinerary and personal situation. Typically, you should have several documents on hand, such as a national ID card or driver's license and a passport that is valid for six months after your intended arrival at Illinois. It is always advisable to seek advice from your airline or a trusted third party, such as IATA.
What is the most popular plane model from St. Louis to Illinois?
Based on momondo bookings for flights between St. Louis and Illinois, the leading plane model is Embraer 175, making up 11.48% of the total bookings. Other popular models include Boeing 737-800 with 10.92%, Boeing 737 MAX 8 with 10.29%, and Boeing 737-700 Passenger/BBJ1 (winglets) with 9.75%.
Best airlines flying from St. Louis to Illinois
Compare and see reviews for airlines that fly from St. Louis to Illinois with momondo
| Airline | Rating | Free Cancellation | Price | ||
|---|---|---|---|---|---|
| PriceFrom $115 | Free Cancellation | Rating 7.2 10,000 reviews | |||
| PriceFrom $118 | Free Cancellation | Rating 6.5 27 reviews | |||
| PriceFrom $124 | Free Cancellation | Rating 7.4 8,702 reviews | |||
| PriceFrom $168 | Free Cancellation | Rating 8.0 4,292 reviews |
Why use momondo?
Why should I use momondo to find a flight deal from St. Louis to Illinois?
momondo compares prices from hundreds of airlines and agents so you can find and book the best deal on flights from St. Louis to Illinois. Millions of users trust and use momondo every year so you are in good hands.
Can I find flights from St. Louis to Illinois with flexible booking policies on momondo?
Flights from St. Louis to Illinois with flexible booking policies can be found by using the search form above and then selecting our dedicated flexible booking filter, which will highlight only the flights where this policy is applied.
How can momondo help me find flights from St. Louis to Illinois?
Once you have performed a search in the form on the page, momondo provides useful filters and insights. We can show you the cheapest days and times to fly as well as help filter your options to help you make an informed choice when booking flights to Illinois from St. Louis.
I’m not ready to book a flight from St. Louis to Illinois right now. Can momondo alert me if prices change?
Yes. momondo can track prices for St. Louis to Illinois flights and alert you when they change. Perform a search to set up the price alert. All that is required is a valid email address.