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Not ready to book? to track prices.Find the cheapest flights from Islip, New York to St. Louis
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Southwest flights from Islip, New York to St. Louis
Our best Southwest deals on Islip, New York to St. Louis flight tickets
Frontier flights from Islip, New York to St. Louis
Our best Frontier deals on Islip, New York to St. Louis flight tickets
See travel insights to St. Louis from
How to get the cheapest flight ticket from Islip, New York 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 day to depart on your flight to St. Louis?
The cheapest day to depart on your flight to St. Louis is on a Tuesday when prices can be found for as low as $329. 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 Sunday because tickets tend to average around $441. 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 Islip, New York in the morning is the least expensive time of day to depart. momondo users have found prices as low as $349 when looking at flights departing in the morning. At noon is when there is more demand to fly to St. Louis, so prices are often more expensive at around $403 per ticket.
What is the cheapest airline that flies from Islip Long Island to Lambert-St Louis?
Southwest and Frontier are the most popular carriers operating from Islip Long Island to Lambert-St Louis
What airlines fly to St. Louis?
United Airlines, Delta and American Airlines are the top three most popular airlines that fly to St. Louis from Islip, New York according to our data. United Airlines is the first choice among our users, with 41% of people opting to fly with this airline when traveling to St. Louis. Keep in mind that there are 6 different airlines that fly to St. Louis on a routine basis, so you have a few additional options to choose from.
When to book flights from Islip, New York to St. Louis
Cheap Islip, New York to St. Louis (ISP to STL) flight deals and tips
Find info about flight duration, direct flights, and airports for your flight from Islip, New York to St. Louis
How far is Islip Long Island to Lambert-St Louis by plane?
There are 912.8 mi between Islip Long Island and Lambert-St Louis. In terms of flight time, this usually takes a little over 5h 05m.
When did momondo last update prices for flights from Islip Long Island Airport to Lambert-St Louis Airport?
Prices for flights from Islip Long Island Airport to Lambert-St Louis Airport are refreshed on a daily basis.
How many operators does momondo search for flights from Islip Long Island Airport to Lambert-St Louis Airport?
As of June 2025, there is 1 operator available to choose from for flights from Islip Long Island Airport to Lambert-St Louis Airport.
How old do you have to be to fly from Islip Long Island Airport to Lambert-St Louis Airport?
The minimum age for a child to fly alone is five, but airlines that offer an unaccompanied minor (UNMR) service may have their own age limitations. Flight duration, scheduling, and layovers are among the considerations that may influence age limits. We recommend that you double-check with the airline you are booking with for travel from Islip Long Island Airport to Lambert-St Louis Airport.
What documentation or ID do you need to fly to Lambert-St Louis Airport?
The travel and health documents you'll need for your trip to Lambert-St Louis Airport 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 Lambert-St Louis Airport. It is always advisable to seek advice from your airline or a trusted third party, such as IATA.
What is the most popular airline from Islip, New York to St. Louis?
Based on momondo bookings for flights between Islip, New York and St. Louis, the leading airline is Southwest, making up 100% of the total bookings.
Best airlines flying from Islip, New York to St. Louis
Compare and see reviews for airlines that fly from Islip, New York to St. Louis with momondo
| Airline | Rating | Free Cancellation | Price | ||
|---|---|---|---|---|---|
| PriceFrom $304 | Free Cancellation | Rating 8.0 4,276 reviews |
Traveling to a place near St. Louis?
Book flights to St. Louis if you plan to visit one of these locationsWhy use momondo?
Why should I use momondo to find a flight deal from Islip to St. Louis?
momondo compares prices from hundreds of airlines and agents so you can find and book the best deal on flights from Islip to St. Louis. Millions of users trust and use momondo every year so you are in good hands.
Can I find flights from Islip to St. Louis with flexible booking policies on momondo?
Yes. momondo allows you to filter the results for Islip to St. Louis flights to just show those with flexible booking policies.
How can momondo help me find flights from Islip to St. Louis?
momondo offers useful filters to help you find the right flight. Choose specific flight times, airports or even what payment method you prefer. We have numerous options to help you book your ideal flight from Islip to St. Louis.
I’m not ready to book a flight from Islip to St. Louis right now. Can momondo alert me if prices change?
Price alerts on flights to St. Louis from Islip are quick and easy to set up on momondo. Simply perform a search and select the price alert feature. It is as simple as that.