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ISP - STL

Find cheap flights from Islip to St. Louis from $168

This is the cheapest round-trip flight price found by a KAYAK user in the last 72 hours by searching for a flight from Islip to St. Louis departing on 5/5. Fares are subject to change and may not be available on all flights or dates of travel. Click the price to replicate the search for this deal.
1 adult
0 bags
Fri 5/24
Fri 5/31

Search hundreds of travel sites at once for deals on flights to St. Louis

 
These are the airlines KAYAK users have selected most often from within our search results in flight searches from Islip to St. Louis, as well as popular online travel agencies
These are the airlines KAYAK users have selected most often from within our search results in flight searches from Islip to St. Louis, as well as popular online travel agencies
In the last 7 days travelers have searched 44,632,927 times on KAYAK, and here is why:

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Cheap flight deals from Islip to St. Louis (ISP-STL)

Here are some of the best deals found on KAYAK recently from the most popular airlines for round-trip flights from Islip to St. Louis that are departing in the next months. While these flights were available on KAYAK in the last 72 hours, prices and availability are subject to change and deals may expire.
Discover the best prices and deals for you by selecting your travel dates.
Choose your dates
9:56 pm - 8:11 pmISP-STL
23h 15m1 stop
7:16 pm - 7:54 amSTL-ISP
11h 38m1 stop
$168Frontier
Find Deal
Sun, May 5 - Sun, May 12
8:27 pm - 7:08 amISP-STL
11h 41m1 stop
9:20 pm - 8:13 amSTL-ISP
9h 53m1 stop
$468Frontier
Find Deal
Thu, May 23 - Mon, May 27

Flights from Islip to St. Louis - Travel Insights & Trends

Get data-powered insights and trends into flights from Islip to St. Louis to help you find the cheapest flights, the best time to fly and much more.

What is the cheapest month to fly from Islip, New York to St. Louis?

To calculate monthly average prices, KAYAK takes all prices for each month over the last year for flights from Islip, New York to St. Louis, removes the top 0.1% to account for outliers, and then takes the median of all values for each month.
The cheapest month for flights from Islip, New York to St. Louis is February, where tickets cost $278 on average. On the other hand, the most expensive months are June and December, where the average cost of tickets is $366 and $362 respectively.

How far in advance should I book a flight from Islip, New York to St. Louis?

To calculate daily average prices, KAYAK takes all prices for each day before departure over the last year for flights from Islip, New York to St. Louis, removes the top 0.1% to account for outliers, and then takes the average of all the values for each month.
To get a below average price on the flight from Islip, New York to St. Louis, you should book around 2 weeks before departure. For the absolute cheapest price, our data suggests you should book 46 days before departure.

Good to know

Cheapest flight

$168
Flight from Islip to St. Louis

When to book flights from Islip to St. Louis

Are your dates flexible? Find out the best times to travel from Islip to St. Louis based on our flight data from the last year. Discover the cheapest month and even day to fly.
Estimated round-trip price
KAYAK looks at all historical flight data for each date to provide a predicted price for one-way trips or round-trips with a duration up to 40 days. While we try to provide actual minimum prices for each date, some prices are predictions and actual prices may differ.

FAQs for booking flights from Islip to St. Louis

  • What is the cheapest flight from Islip, New York to St. Louis?

    In the last 3 days, the lowest price for a flight from Islip, New York to St. Louis was $215 for a one-way ticket and $168 for a round-trip.

  • Do I need a passport to fly between Islip and St. Louis?

    A passport is not required to fly from Islip to St. Louis.

  • Which airports will I be using when flying from Islip to St. Louis?

    Islip airport is called Islip Long Island and the only airport in St. Louis is Lambert-St Louis.

  • Which aircraft models fly most regularly from Islip to St. Louis?

    We unfortunately don’t have that data for this specific route.

  • How does KAYAK find such low prices on flights from Islip to St. Louis?

    KAYAK is a travel search engine. That means we look across the web to find the best prices we can find for our users. With over 2 billion flight queries processed yearly, we are able to display a variety of prices and options on flights from Islip to St. Louis.

  • How does KAYAK's flight Price Forecast tool help me choose the right time to buy my flight ticket from Islip to St. Louis?

    KAYAK’s flight Price Forecast tool uses historical data to determine whether the price for a flight to St. Louis from Islip is likely to change within 7 days, so travelers know whether to wait or book now.

  • What is the Hacker Fare option on flights from Islip to St. Louis?

    Hacker Fares allow you to combine one-way tickets in order to save you money over a traditional round-trip ticket. You could then fly to St. Louis with an airline and back to Islip with another airline. Booking your flights between Islip and STL can sometimes prove cheaper using this method.

  • What is KAYAK's "flexible dates" feature and why should I care when looking for a flight from Islip to St. Louis?

    Sometimes travel dates aren't set in stone. If your preferred travel dates have some wiggle room, flexible dates will show you all the options when flying to St. Louis from Islip up to 3 days before/after your preferred dates. You can then pick the flights that suit you best.

See more FAQs

Book cheap flights from Islip to St. Louis

Recent one-way flight deals

 
Only flying one-way? Below are some of the best one-way flight deals from Islip to St. Louis found on KAYAK in the last 72 hours.
5/23Thu
1 stopFrontier
11h 41mISP-STL
$215

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Islip - St. Louis Flights

Departure:

Islip (ISP)United States

Destination:

St. Louis (STL)United States

Return flight deals:

St. Louis - Islip

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