Which airports can I use when flying from Islip to St. Louis?

Flights from Islip to St. Louis usually depart from Islip Long Island (ISP) and arrive at Lambert-St Louis (STL).

What cabin classes can I book on flights from Islip to St. Louis?

Only Economy Class is available on flights from Islip to St. Louis.

Which airports do connecting flights from Islip to St. Louis pass through?

Most connecting flights from Islip to St. Louis pass through Baltimore/Washington (BWI), which handles 100% of one-stop traffic on this route.

Can I save money by using flexible dates for flights from Islip to St. Louis?

Yes. Flexible dates can save you up to 40% on flights from Islip to St. Louis. Wednesday is the cheapest departure day at $246 round-trip on average, while Friday is the most expensive at $406, a difference of $160. KAYAK's flexible dates feature shows options up to 3 days before and after your selected dates, making it easier to compare nearby fares.

What popular places can I visit in St. Louis?

Some of the most popular sights in St. Louis are Busch Stadium, Enterprise Center and America's Center Convention Complex. These are among the most viewed places in St. Louis on KAYAK.

How long is a flight from Islip to St. Louis?

A nonstop flight from Islip to St. Louis takes 00m, covering 926 miles.

Do I need a passport to fly from Islip to St. Louis?

No, a passport is not required for this domestic route, but you will need a real ID-compliant driver's license, a state ID or another TSA-accepted form of identification.

Have flight prices from Islip to St. Louis changed much recently?

Yes. Based on fares seen in the past 5 days, round-trip prices on this route showed a wide range, from about $321 to $752. That means the highest observed fare was about 2x higher than the lowest one.

How are flight prices from Islip to St. Louis looking right now?

One-way fares from Islip to St. Louis are currently higher than usual. Average one-way flight prices are about $202, which is 39% above the typical average for this route.

What is the time difference between Islip and St. Louis?

St. Louis is 1 hour behind Islip (Central Time vs Eastern Time). Plan for the time shift when scheduling connections or first-day activities.

What car rental options are available at Lambert-St Louis Airport (STL)?

Lambert-St Louis Airport (STL) hosts 5 major car rental companies, with daily rates averaging $78 for economy cars. Top options include: • Hertz • Budget • Alamo • Enterprise Rent-A-Car • Payless

How much should I expect to pay for a Islip to St. Louis flight?

Round-trip flights from Islip to St. Louis range from $288 to $359, with an average of $324 over the past 12 months. Anything below $288 counts as a good deal.

How much is a round-trip flight from Islip to St. Louis?

Round-trip flights from Islip to St. Louis typically range from $288 to $359. The lowest price found in the past 5 days was $321, on Southwest.

Which airline is the cheapest to fly from Islip to St. Louis?

Southwest ($321) and Frontier ($563) are the cheapest airlines to fly round-trip from Islip to St. Louis according to KAYAK data over the last 5 days.

What is the cheapest layover airport when flying from Islip to St. Louis?

Flights via Baltimore/Washington (BWI) offer the most affordable fares, with an average round-trip price of $304. Based on KAYAK data over the past 3 months.

When flying from Islip to St. Louis which airport offers the shortest layover?

Baltimore/Washington (BWI) had the shortest average connection time for Islip to St. Louis layovers at 3h 58m over the past 3 months.

$118 CHEAP FLIGHTS from Islip to St. Louis (ISP - STL)

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Never overpay with our price tracking tools.

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Cheapest round-trip

$321

Typical prices: $288-$359

Southwest

Fri 11/16Sun 11/18

ISP - STL • 1 stop

Cheapest one-way

$118

Typical prices: $129-$156

Frontier

Thu 12/6

ISP - STL • 1 stop

Nonstop flights

Not available

There are currently no direct flights between Islip and St. Louis. You'll need to take a connecting flight to reach the destination.

Insights

When to travel

September

Cheapest • 24% price drop

September

Most popular

Good to know

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We hope you love your trip to St. Louis!

Flight Deals

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

Discover the best prices for you by selecting your travel dates on KAYAK.

Round-trip

One-way

Recent round-trip flight deals from Islip to St. Louis

Mon, Nov 16 - Wed, Nov 18

4:05 pm - 10:15 pmISP Islip Long Island-STL Lambert-St Louis

7h 10m1 stop Baltimore/Washington

6:20 am - 4:15 pmSTL Lambert-St Louis-ISP Islip Long Island

8h 55m2 stops Chicago Midway Baltimore/Washington

$321Southwest

Mon, Nov 16 - Wed, Nov 18

4:05 pm - 10:15 pmISP Islip Long Island-STL Lambert-St Louis

7h 10m1 stop Baltimore/Washington

6:35 am - 4:15 pmSTL Lambert-St Louis-ISP Islip Long Island

8h 40m1 stop Baltimore/Washington

$321Southwest

Sat, Nov 21 - Wed, Nov 25

5:05 pm - 11:30 pmISP Islip Long Island-STL Lambert-St Louis

7h 25m1 stop Baltimore/Washington

3:30 pm - 11:40 pmSTL Lambert-St Louis-ISP Islip Long Island

7h 10m1 stop Orlando

$343Southwest

Sat, Dec 12 - Sun, Dec 13

3:30 pm - 7:15 pmISP Islip Long Island-STL Lambert-St Louis

4h 45m1 stop Baltimore/Washington

5:10 pm - 11:35 pmSTL Lambert-St Louis-ISP Islip Long Island

5h 25m1 stop Baltimore/Washington

$343Southwest

Mon, Nov 16 - Wed, Nov 18

12:30 pm - 7:25 pmISP Islip Long Island-STL Lambert-St Louis

7h 55m2 stops Baltimore/Washington Pittsburgh

6:20 am - 4:15 pmSTL Lambert-St Louis-ISP Islip Long Island

8h 55m2 stops Chicago Midway Baltimore/Washington

$343Southwest

Sat, Dec 12 - Sun, Dec 13

12:45 pm - 7:35 pmISP Islip Long Island-STL Lambert-St Louis

7h 50m2 stops Baltimore/Washington Chicago Midway

5:10 pm - 11:35 pmSTL Lambert-St Louis-ISP Islip Long Island

5h 25m1 stop Baltimore/Washington

$348Southwest

Sat, Nov 21 - Wed, Nov 25

5:05 pm - 11:30 pmISP Islip Long Island-STL Lambert-St Louis

7h 25m1 stop Baltimore/Washington

2:35 pm - 11:40 pmSTL Lambert-St Louis-ISP Islip Long Island

8h 05m2 stops Nashville Intl Orlando

$348Southwest

Sat, Dec 12 - Sun, Dec 13

12:45 pm - 7:35 pmISP Islip Long Island-STL Lambert-St Louis

7h 50m2 stops Baltimore/Washington Chicago Midway

4:40 pm - 11:35 pmSTL Lambert-St Louis-ISP Islip Long Island

5h 55m2 stops Charlotte Douglas Baltimore/Washington

$353Southwest

Sun, Nov 22 - Mon, Nov 23

4:40 pm - 11:59 pmISP Islip Long Island-STL Lambert-St Louis

8h 19m1 stop Orlando

3:04 pm - 3:45 pmSTL Lambert-St Louis-ISP Islip Long Island

23h 41m2 stops Denver Intl Orlando

$563Frontier

Sun, Nov 22 - Mon, Nov 23

4:40 pm - 11:59 pmISP Islip Long Island-STL Lambert-St Louis

8h 19m1 stop Orlando

3:04 pm - 3:45 pmSTL Lambert-St Louis-ISP Islip Long Island

23h 41m2 stops Denver Intl Orlando

$626Frontier

Booking Insights

Price, demand and travel trends for Islip to St. Louis flights

Use KAYAK data on prices, travel dates, airlines and seasonal trends to compare options and book flights with more confidence.

Prices

Airlines

Layovers

How much is a round-trip flight from Islip to St. Louis? This analysis is based on the cheapest round-trip price found on KAYAK in the last 12 months by searching for a flight from Islip to St. Louis departing in november.

Find deals

Cheapest flight	$118

One-way 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.

What cabin classes can I book on flights from Islip to St. Louis?
Only Economy Class is available on flights from Islip to St. Louis.
How long is a flight from Islip to St. Louis?
A nonstop flight from Islip to St. Louis takes 00m, covering 926 miles.
Do I need a passport to fly from Islip to St. Louis?
No, a passport is not required for this domestic route, but you will need a real ID-compliant driver's license, a state ID or another TSA-accepted form of identification.
How much should I expect to pay for a Islip to St. Louis flight?
Round-trip flights from Islip to St. Louis range from $288 to $359, with an average of $324 over the past 12 months. Anything below $288 counts as a good deal.
Have flight prices from Islip to St. Louis changed much recently?
Yes. Based on fares seen in the past 5 days, round-trip prices on this route showed a wide range, from about $321 to $752. That means the highest observed fare was about 2x higher than the lowest one.
How are flight prices from Islip to St. Louis looking right now?
One-way fares from Islip to St. Louis are currently higher than usual. Average one-way flight prices are about $202, which is 39% above the typical average for this route.
What car rental options are available at Lambert-St Louis Airport (STL)?
Lambert-St Louis Airport (STL) hosts 5 major car rental companies, with daily rates averaging $78 for economy cars. Top options include:

• Hertz
• Budget
• Alamo
• Enterprise Rent-A-Car
• Payless
Which airports can I use when flying from Islip to St. Louis?
Flights from Islip to St. Louis usually depart from Islip Long Island (ISP) and arrive at Lambert-St Louis (STL).
Which airports do connecting flights from Islip to St. Louis pass through?
Most connecting flights from Islip to St. Louis pass through Baltimore/Washington (BWI), which handles 100% of one-stop traffic on this route.
Can I save money by using flexible dates for flights from Islip to St. Louis?
Yes. Flexible dates can save you up to 40% on flights from Islip to St. Louis. Wednesday is the cheapest departure day at $246 round-trip on average, while Friday is the most expensive at $406, a difference of $160.

KAYAK's flexible dates feature shows options up to 3 days before and after your selected dates, making it easier to compare nearby fares.
What is the time difference between Islip and St. Louis?
St. Louis is 1 hour behind Islip (Central Time vs Eastern Time). Plan for the time shift when scheduling connections or first-day activities.
What popular places can I visit in St. Louis?
Some of the most popular sights in St. Louis are Busch Stadium, Enterprise Center and America's Center Convention Complex. These are among the most viewed places in St. Louis on KAYAK.

If your dates are flexible, aim for a Wednesday departure and avoid flying on Friday. On this route, Wednesday flights average $246, about $160 less than Friday fares (39% savings) based on the last 12 months.
If you can choose when to travel, plan your Islip to St. Louis trip for September. Fares historically average $246 round-trip in that month - typically $160 less than the most expensive month, which is July (based on the last 12 months).
If you're arriving late at night and need somewhere to stay, check out these hotels close to Lambert-St Louis Airport.

• Renaissance St. Louis Airport Hotel
• Drury Inn & Suites St. Louis Airport
• DoubleTree by Hilton St. Louis Airport

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ISP - STL

$118 Find Cheap Flights from Islip to St. Louis - Compare and Save

Everything you should know

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

Recent round-trip flight deals from Islip to St. Louis

Recent one-way flight deals from Islip to St. Louis

Price, demand and travel trends for Islip to St. Louis flights

How much is a round-trip flight from Islip to St. Louis?

Which airline is the cheapest to fly from Islip to St. Louis?

What is the cheapest layover airport when flying from Islip to St. Louis?

When flying from Islip to St. Louis which airport offers the shortest layover?

Key details for Islip to St. Louis flights

Cheapest flight

When to book flights from Islip to St. Louis

Your Islip to St. Louis flight questions, answered

Your guide to booking Islip to St. Louis flights

More options for your flight from Islip to St. Louis

Complete your trip to St. Louis with a hotel stay or car rental

Information on your arrival and departure airports

Cabin class types available on flights from Islip to St. Louis

Find direct flights to and from Islip and St. Louis

Flights from domestic origins to St. Louis

Flights to other popular destinations

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