Cheap flights from Illinois to St. Louis from $73
This is the cheapest one-way flight price found by a momondo user in the last 72 hours by searching for a flight from Illinois to St. Louis departing on 6/22. 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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How to get the cheapest flight ticket from Illinois to St. Louis
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 St. Louis?
In general, September is the cheapest month to fly from Illinois to St. Louis. Due to it being the ‘off-season’ during this time, you can expect flight prices to be around $246. The month of June is another great option to travel to St. Louis, with average flight prices from Illinois averaging around $247.
What is the cheapest day to depart on your flight to St. Louis?
The cheapest day to depart on your flight to St. Louis is on a Thursday when prices can be found for as low as $299. This is often the case because there is less demand to fly during this day of the week. If your travel schedule is flexible, try to avoid departing on a Monday because tickets tend to average around $510. These prices are subject to change though, so be sure to set up a Price Alert for flights to St. Louis.
What is the cheapest time of day to depart on your flight to St. Louis?
Flying to St. Louis from Illinois in the evening is the least expensive time of day to depart. momondo users have found prices as low as $281 when looking at flights departing in the evening. In the morning is when there is more demand to fly to St. Louis, so prices are often more expensive at around $423 per ticket.
What is the cheapest Illinois to Lambert-St Louis flight route?
Fly from Chicago O'Hare Intl to Lambert-St Louis for the best Illinois - Lambert-St Louis flight prices
How far in advance should I book a flight to St. Louis?
You are more likely to see cheaper flights to St. Louis from Illinois when booking 18 weeks ahead of your departure date. In general, you can expect to find flights to St. Louis for around $266 when searching 18 weeks out.However, flight prices might be lower outside of this timeframe. For example, people recently found flights to St. Louis from Illinois for as low as $150 on momondo.
What cabin class options are available on Illinois to Lambert-St Louis flights?
There are 4 cabin classes available to choose from on Illinois to Lambert-St Louis 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 Illinois to Lambert-St Louis?
Southern / Mokulele, Frontier, and United Airlines are the most popular carriers operating from Illinois to Lambert-St Louis
What airlines fly to St. Louis?
American Airlines, United Airlines and Contour are the top three most popular airlines that fly to St. Louis from Illinois according to our data. American Airlines is the first choice among our users, with 49% of people opting to fly with this airline when traveling to St. Louis. Keep in mind that there are 5 different airlines that fly to St. Louis on a routine basis, so you have a few additional options to choose from.
How many flights depart from Illinois to St. Louis on average per day?
As of May 2025, there are 65 flights per day flying from Illinois to St. Louis. The most common time of day flights depart is 8:00PM, with 44% of flights taking off in the afternoon.
How many flights depart from Illinois to St. Louis on average per week?
As of May 2025, there are 459 flights per week flying from Illinois to St. Louis. The most common day of the week flights depart is Mon, with 16% of flights taking off on this day.
Cheap Illinois to St. Louis flight deals and tips
Find info about flight duration, direct flights, and airports for your flight from Illinois to St. Louis
When did momondo last update prices for flights from Illinois to Lambert-St Louis Airport?
Prices for flights from Illinois to Lambert-St Louis Airport refresh daily.
How many operators does momondo search for flights from Illinois to Lambert-St Louis Airport?
There are 4 operators available for flights from Illinois to Lambert-St Louis Airport as of May 2025.
How old do you have to be to fly from Illinois to Lambert-St Louis Airport?
The minimum age for a child to fly alone is five, but airlines offering an unaccompanied minor (UNMR) service may have their age restrictions, such as regulations concerning flight duration, timing, and layovers. It is recommended that you verify with the airline you are booking with for travel from Illinois to Lambert-St Louis Airport.
What documentation or ID do you need to fly to Lambert-St Louis Airport?
The required travel and health documents for your Lambert-St Louis Airport trip may vary depending on your itinerary and personal circumstances. As a general rule, you should carry multiple documents, including a national ID card or driver's license and a passport valid for six months after your intended arrival at Lambert-St Louis Airport. We recommend that you seek guidance from your airline or a reliable third party such as IATA.
What is the most popular plane model from Illinois to St. Louis?
momondo data reveals that the most frequently booked plane model on the route from Illinois to St. Louis is Airbus A319, representing 14.48% of all bookings. The subsequent popular models are Embraer 175 at 10.54%, Boeing 737 MAX 8 at 10.03%, and Embraer 170 at 9.09%.
Best airlines flying from Illinois to St. Louis
Compare and see reviews for airlines that fly from Illinois to St. Louis with momondo
| Airline | Rating | Free Cancellation | Price | ||
|---|---|---|---|---|---|
| PriceFrom $116 | Free Cancellation | Rating 7.2 10,000 reviews | |||
| PriceFrom $116 | Free Cancellation | Rating 8.0 4,290 reviews | |||
| PriceFrom $117 | Free Cancellation | Rating 6.5 27 reviews | |||
| PriceFrom $140 | Free Cancellation | Rating 7.4 8,724 reviews |
Traveling to a place near St. Louis?
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Why should I use momondo to find a flight deal from Illinois to St. Louis?
It is quick and easy to find Illinois to St. Louis flights on momondo. We search and return numerous flight options from various airlines and agents. You can then use our filters to narrow your search until you have found the most convenient flight to St. Louis that suits you.
Can I find flights from Illinois to St. Louis with flexible booking policies on momondo?
All flight searches from Illinois to St. Louis on momondo can be filtered to show those which offer flexible booking policies.
How can momondo help me find flights from Illinois to St. Louis?
Once all potential Illinois to St. Louis flight options are in front of you, momondo lets you sort and filter flights based on preferences such as airline, price and flight times amongst many other options.
I’m not ready to book a flight from Illinois to St. Louis right now. Can momondo alert me if prices change?
Yes momondo offers price alerts on flights to St. Louis from Illinois. After performing a search on this page you should be able to see the price alert set up feature. Simply provide a valid email address and momondo will instantly alert you when prices change.