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

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

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

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

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

Most connecting flights from St. Louis to Islip pass through Baltimore/Washington (BWI), which handles 100% of one-stop traffic on this route. Other layover airports each see under 5%.

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

Yes. Being flexible with your travel dates can save you up to 57% on the St. Louis to Islip route. Wednesday is the cheapest departure day at $258 round-trip on average, while Thursday is the most expensive at $597, a difference of $339. KAYAK's flexible dates feature shows options up to 3 days before and after your selected dates, making it easier to compare nearby fares.

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

A nonstop flight from St. Louis to Islip takes 0h 00m, covering 926 miles.

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

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 St. Louis to Islip changed much recently?

Yes. Based on fares seen in the past 5 days, round-trip prices on this route varied from about $341 to $475. That means the highest observed fare was about 39% higher than the lowest one.

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

One-way fares from St. Louis to Islip are currently higher than usual. Average one-way flight prices are about $210, which is 11% above the typical average for this route.

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

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

What car rental options are available at Islip Long Island Airport (ISP)?

Islip Long Island Airport (ISP) hosts 5 major car rental companies, with daily rates starting from around $36 for economy cars. Top options include: • Budget • Enterprise Rent-A-Car • Avis • National • Empire Rent A Car

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

Round-trip flights from St. Louis to Islip range from $285 to $540, with an average of $403 over the past 12 months. Anything below $285 counts as a good deal.

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

Frontier ($341) and Southwest ($361) are the cheapest airlines to fly round-trip from St. Louis to Islip according to KAYAK data over the last 5 days.

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

Flights via Baltimore/Washington (BWI) offer the most affordable fares, with an average round-trip price of $389. Based on KAYAK data over the past 3 months.

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

Baltimore/Washington (BWI) had the shortest average connection time for St. Louis to Islip layovers at 231 minutes over the past 3 months.

$133 CHEAP FLIGHTS from St. Louis to Islip (STL - ISP)

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Cheapest round-trip

$341

Typical prices: $285-$540

Frontier

Tue 11/13Thu 11/15

STL - ISP • 1 stop

Cheapest one-way

$133

Typical prices: $119-$303

Multiple Airlines

Tue 10/23

STL - ISP • 2 stops

Nonstop flights

Not available

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

Insights

When to travel

October

Cheapest • 46% price drop

June

Most popular

Good to know

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We hope you love your trip to Islip!

Flight Deals

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

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

Round-trip

One-way

Last minute

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

Fri, Nov 13 - Sun, Nov 15

4:26 pm - 5:31 pmSTL Lambert-St Louis-ISP Islip Long Island

24h 05m1 stop Orlando

6:33 pm - 11:16 pmISP Islip Long Island-STL Lambert-St Louis

29h 43m1 stop Orlando

$341Frontier

Fri, Nov 13 - Sun, Nov 15

1:05 pm - 11:35 pmSTL Lambert-St Louis-ISP Islip Long Island

9h 30m2 stops Chicago Midway Baltimore/Washington

4:45 pm - 12:10 amISP Islip Long Island-STL Lambert-St Louis

8h 25m1 stop Orlando

$361Southwest

Fri, Nov 13 - Sun, Nov 15

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

5h 55m2 stops Charlotte Douglas Baltimore/Washington

5:35 am - 12:20 pmISP Islip Long Island-STL Lambert-St Louis

7h 45m2 stops Baltimore/Washington Chicago Midway

$366Southwest

Fri, Oct 2 - Mon, Oct 5

4:05 pm - 11:10 pmSTL Lambert-St Louis-ISP Islip Long Island

6h 05m1 stop Orlando

5:40 pm - 11:20 pmISP Islip Long Island-STL Lambert-St Louis

6h 40m1 stop Baltimore/Washington

$422Southwest

Fri, Oct 2 - Mon, Oct 5

4:05 pm - 11:10 pmSTL Lambert-St Louis-ISP Islip Long Island

6h 05m1 stop Orlando

5:40 pm - 12:35 amISP Islip Long Island-STL Lambert-St Louis

7h 55m2 stops Baltimore/Washington Orlando

$427Southwest

Fri, Oct 2 - Mon, Oct 5

4:30 pm - 11:35 pmSTL Lambert-St Louis-ISP Islip Long Island

6h 05m2 stops Charleston Baltimore/Washington

5:40 pm - 12:35 amISP Islip Long Island-STL Lambert-St Louis

7h 55m2 stops Baltimore/Washington Orlando

$432Southwest

Sat, Sep 26 - Wed, Sep 30

6:45 am - 2:30 pmSTL Lambert-St Louis-ISP Islip Long Island

6h 45m1 stop Baltimore/Washington

3:20 pm - 9:15 pmISP Islip Long Island-STL Lambert-St Louis

6h 55m1 stop Baltimore/Washington

$441Southwest

Sat, Sep 26 - Wed, Sep 30

6:45 am - 2:30 pmSTL Lambert-St Louis-ISP Islip Long Island

6h 45m1 stop Baltimore/Washington

6:05 am - 12:10 pmISP Islip Long Island-STL Lambert-St Louis

7h 05m2 stops Baltimore/Washington Atlanta Hartsfield-Jackson

$446Southwest

Sat, Sep 26 - Wed, Sep 30

5:45 am - 2:30 pmSTL Lambert-St Louis-ISP Islip Long Island

7h 45m2 stops Chicago Midway Baltimore/Washington

6:05 am - 11:20 amISP Islip Long Island-STL Lambert-St Louis

6h 15m2 stops Baltimore/Washington Chicago Midway

$475Southwest

Booking Insights

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

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

Prices

Airlines

Layovers

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

Round-trip flights from St. Louis to Islip start at $341. Prices are typical for this route right now, with typical round-trip fares ranging from $285 to $540. The lowest price found in the past 5 days was $341 on Frontier.

Find deals

Low season	January
High season	June
Cheapest flight	$133

Most popular time to fly and prices are also 29% lower on average.

Flight from St. Louis to Islip

When to book flights from St. Louis to Islip

Are your dates flexible? Find out the best times to travel from St. Louis to Islip 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.

Which airports can I use when flying from St. Louis to Islip?
Flights from St. Louis to Islip usually depart from Lambert-St Louis (STL) and arrive at Islip Long Island (ISP).
What cabin classes can I book on flights from St. Louis to Islip?
Only Economy Class is available on flights from St. Louis to Islip.
Which airports do connecting flights from St. Louis to Islip pass through?
Most connecting flights from St. Louis to Islip pass through Baltimore/Washington (BWI), which handles 100% of one-stop traffic on this route. Other layover airports each see under 5%.
Can I save money by using flexible dates for flights from St. Louis to Islip?
Yes. Being flexible with your travel dates can save you up to 57% on the St. Louis to Islip route. Wednesday is the cheapest departure day at $258 round-trip on average, while Thursday is the most expensive at $597, a difference of $339. KAYAK's flexible dates feature shows options up to 3 days before and after your selected dates, making it easier to compare nearby fares.
How long is a flight from St. Louis to Islip?
A nonstop flight from St. Louis to Islip takes 0h 00m, covering 926 miles.
Do I need a passport to fly from St. Louis to Islip?
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 St. Louis to Islip changed much recently?
Yes. Based on fares seen in the past 5 days, round-trip prices on this route varied from about $341 to $475. That means the highest observed fare was about 39% higher than the lowest one.
How are flight prices from St. Louis to Islip looking right now?
One-way fares from St. Louis to Islip are currently higher than usual. Average one-way flight prices are about $210, which is 11% above the typical average for this route.
What is the time difference between St. Louis and Islip?
Islip is 1 hour ahead of St. Louis (Eastern Time vs Central Time). Plan for the time shift when scheduling connections or first-day activities.
What car rental options are available at Islip Long Island Airport (ISP)?
Islip Long Island Airport (ISP) hosts 5 major car rental companies, with daily rates starting from around $36 for economy cars. Top options include:
• Budget
• Enterprise Rent-A-Car
• Avis
• National
• Empire Rent A Car
How much should I expect to pay for a St. Louis to Islip flight?
Round-trip flights from St. Louis to Islip range from $285 to $540, with an average of $403 over the past 12 months. Anything below $285 counts as a good deal.

If your dates can be flexible, aim for a Wednesday departure instead of Thursday. On this route, Wednesday flights average $258 - about $339 less than Thursday (57% savings) based on the last 12 months.
If you can choose when to travel, plan your St. Louis to Islip trip for October. Fares historically average $218 round-trip in that month - typically $480 less than the most expensive month, which is May (based on the last 12 months).

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STL - ISP

$133 Find Cheap Flights from St. Louis to Islip - Compare and Save

Everything you should know

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

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

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

Recent last minute flight deals from St. Louis to Islip

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

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

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

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

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

Key details for St. Louis to Islip flights

Low season

High season

Cheapest flight

When to book flights from St. Louis to Islip

Your St. Louis to Islip flight questions, answered

Your guide to booking St. Louis to Islip flights

More options for your flight from St. Louis to Islip

Complete your trip to Islip with a hotel stay or car rental

Information on your arrival and departure airports

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

Find direct flights to and from St. Louis and Islip

Flights from domestic origins to Islip

Flights to other popular destinations

Find deals for your return flight