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Cheap flights from Islip, New York to St. Louis from $400

1 adult
1 adult, Economy, 0 bags

Find the cheapest flights from Islip, New York to St. Louis

Cheap round-trip flights

Enter your travel dates to find the best prices.
Southwest Logo
12:30 pm - 6:05 pmISP  Islip Long Island-STL Lambert-St Louis
6h 35m1 stop Baltimore/Washington
Southwest Logo
3:30 pm - 11:40 pmSTL  Lambert-St Louis-ISP Islip Long Island
7h 10m1 stop Orlando
$400Southwest
Tue, Nov 17 - Tue, Nov 24
Southwest Logo
12:30 pm - 7:25 pmISP  Islip Long Island-STL Lambert-St Louis
7h 55m2 stops Baltimore/Washington Pittsburgh
Southwest Logo
3:30 pm - 11:40 pmSTL  Lambert-St Louis-ISP Islip Long Island
7h 10m1 stop Orlando
$405Southwest
Tue, Nov 17 - Tue, Nov 24
Southwest Logo
5:35 am - 12:30 pmISP  Islip Long Island-STL Lambert-St Louis
7h 55m1 stop Orlando
Southwest Logo
6:35 am - 4:15 pmSTL  Lambert-St Louis-ISP Islip Long Island
8h 40m1 stop Baltimore/Washington
$419Southwest
Wed, Dec 30 - Fri, Jan 1
Southwest Logo
5:35 am - 1:55 pmISP  Islip Long Island-STL Lambert-St Louis
9h 20m2 stops Orlando Nashville Intl
Southwest Logo
6:35 am - 4:15 pmSTL  Lambert-St Louis-ISP Islip Long Island
8h 40m1 stop Baltimore/Washington
$425Southwest
Wed, Dec 30 - Fri, Jan 1
Southwest Logo
5:35 am - 1:55 pmISP  Islip Long Island-STL Lambert-St Louis
9h 20m2 stops Orlando Nashville Intl
Southwest Logo
6:20 am - 4:15 pmSTL  Lambert-St Louis-ISP Islip Long Island
8h 55m2 stops Chicago Midway Baltimore/Washington
$456Southwest
Wed, Dec 30 - Fri, Jan 1
Southwest Logo
4:05 pm - 10:00 pmISP  Islip Long Island-STL Lambert-St Louis
6h 55m2 stops Baltimore/Washington Nashville Intl
Southwest Logo
10:15 am - 11:40 pmSTL  Lambert-St Louis-ISP Islip Long Island
12h 25m2 stops Detroit Metropolitan Wayne County Orlando
$471Southwest
Tue, Nov 17 - Tue, Nov 24
Frontier Logo
4:40 pm - 11:59 pmISP  Islip Long Island-STL Lambert-St Louis
8h 19m1 stop Orlando
Frontier Logo
5:15 pm - 3:45 pmSTL  Lambert-St Louis-ISP Islip Long Island
21h 30m2 stops Las Vegas Harry Reid Intl Orlando
$1,058Frontier
Mon, Nov 23 - Sun, Nov 29
Frontier Logo
4:40 pm - 11:59 pmISP  Islip Long Island-STL Lambert-St Louis
8h 19m1 stop Orlando
Frontier Logo
5:15 pm - 3:45 pmSTL  Lambert-St Louis-ISP Islip Long Island
21h 30m2 stops Las Vegas Harry Reid Intl Orlando
$1,095Frontier
Sun, Nov 22 - Sun, Nov 29
Frontier Logo
4:40 pm - 11:59 pmISP  Islip Long Island-STL Lambert-St Louis
8h 19m1 stop Orlando
Frontier Logo
5:15 pm - 3:45 pmSTL  Lambert-St Louis-ISP Islip Long Island
21h 30m2 stops Las Vegas Harry Reid Intl Orlando
$1,117Frontier
Tue, Nov 24 - Sun, Nov 29
Frontier Logo
4:40 pm - 11:59 pmISP  Islip Long Island-STL Lambert-St Louis
8h 19m1 stop Orlando
Frontier Logo
5:15 pm - 3:45 pmSTL  Lambert-St Louis-ISP Islip Long Island
21h 30m2 stops Las Vegas Harry Reid Intl Orlando
$1,131Frontier
Wed, Nov 25 - Sun, Nov 29

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Frontier flights from Islip, New York to St. Louis

Our best Frontier deals on Islip, New York to St. Louis flight tickets
Frontier
Nov 23
ISP4:40 pmIslip Long Island
8h 19m
1 stop
STL11:59 pmLambert-St Louis
Nov 29
STL5:15 pmLambert-St Louis
21h 30m
2 stops
ISP3:45 pmIslip Long Island
$1,058
Frontier
Nov 22
ISP4:40 pmIslip Long Island
8h 19m
1 stop
STL11:59 pmLambert-St Louis
Nov 29
STL5:15 pmLambert-St Louis
21h 30m
2 stops
ISP3:45 pmIslip Long Island
$1,095
Frontier
Nov 24
ISP4:40 pmIslip Long Island
8h 19m
1 stop
STL11:59 pmLambert-St Louis
Nov 29
STL5:15 pmLambert-St Louis
21h 30m
2 stops
ISP3:45 pmIslip Long Island
$1,117

Southwest flights from Islip, New York to St. Louis

Our best Southwest deals on Islip, New York to St. Louis flight tickets
Southwest
Nov 17
ISP12:30 pmIslip Long Island
6h 35m
1 stop
STL6:05 pmLambert-St Louis
Nov 24
STL3:30 pmLambert-St Louis
7h 10m
1 stop
ISP11:40 pmIslip Long Island
$400
Southwest
Nov 17
ISP12:30 pmIslip Long Island
7h 55m
2 stops
STL7:25 pmLambert-St Louis
Nov 24
STL3:30 pmLambert-St Louis
7h 10m
1 stop
ISP11:40 pmIslip Long Island
$405
Southwest
Dec 30
ISP5:35 amIslip Long Island
7h 55m
1 stop
STL12:30 pmLambert-St Louis
Jan 1
STL6:35 amLambert-St Louis
8h 40m
1 stop
ISP4:15 pmIslip Long Island
$419

momondo Fare Finder

 
Use the filters below to find and compare flights from Islip, New York to St. Louis that are best for you.

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Depart

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Price

Cheapest round-trip
Quickest round-trip

IslipSt. Louis

ISP Islip Long Island - STL Lambert-St Louis

ISPSTL

Islip Long Island

Tue 11/17

12:30 pm-6:05 pm

1 stop6h 35m

Lambert-St Louis

Tue 11/24

3:30 pm-11:40 pm

1 stop7h 10m

$400

IslipSt. Louis

ISP Islip Long Island - STL Lambert-St Louis

ISPSTL

Islip Long Island

Tue 11/17

12:30 pm-7:25 pm

2 stops7h 55m

Lambert-St Louis

Tue 11/24

3:30 pm-11:40 pm

1 stop7h 10m

$405

IslipSt. Louis

ISP Islip Long Island - STL Lambert-St Louis

ISPSTL

Islip Long Island

Wed 12/30

5:35 am-12:30 pm

1 stop7h 55m

Lambert-St Louis

Fri 1/1

6:35 am-4:15 pm

1 stop8h 40m

$419

IslipSt. Louis

ISP Islip Long Island - STL Lambert-St Louis

ISPSTL

Islip Long Island

Wed 12/30

5:35 am-1:55 pm

2 stops9h 20m

Lambert-St Louis

Fri 1/1

6:35 am-4:15 pm

1 stop8h 40m

$425

IslipSt. Louis

ISP Islip Long Island - STL Lambert-St Louis

ISPSTL

Islip Long Island

Wed 12/30

5:35 am-1:55 pm

2 stops9h 20m

Lambert-St Louis

Fri 1/1

6:20 am-4:15 pm

2 stops8h 55m

$456

IslipSt. Louis

ISP Islip Long Island - STL Lambert-St Louis

ISPSTL

Islip Long Island

Tue 11/17

4:05 pm-10:00 pm

2 stops6h 55m

Lambert-St Louis

Tue 11/24

10:15 am-11:40 pm

2 stops12h 25m

$471

IslipSt. Louis

ISP Islip Long Island - STL Lambert-St Louis

ISPSTL

Islip Long Island

Mon 11/23

4:40 pm-11:59 pm

1 stop8h 19m

Lambert-St Louis

Sun 11/29

5:15 pm-3:45 pm

2 stops21h 30m

$1,058

IslipSt. Louis

ISP Islip Long Island - STL Lambert-St Louis

ISPSTL

Islip Long Island

Sun 11/22

4:40 pm-11:59 pm

1 stop8h 19m

Lambert-St Louis

Sun 11/29

5:15 pm-3:45 pm

2 stops21h 30m

$1,095

IslipSt. Louis

ISP Islip Long Island - STL Lambert-St Louis

ISPSTL

Islip Long Island

Tue 11/24

4:40 pm-11:59 pm

1 stop8h 19m

Lambert-St Louis

Sun 11/29

5:15 pm-3:45 pm

2 stops21h 30m

$1,117

IslipSt. Louis

ISP Islip Long Island - STL Lambert-St Louis

ISPSTL

Islip Long Island

Wed 11/25

4:40 pm-11:59 pm

1 stop8h 19m

Lambert-St Louis

Sun 11/29

5:15 pm-3:45 pm

2 stops21h 30m

$1,131

Flights are sorted by cheapest round-trip flights first.

Showing 1-10 of 11 resultsSorted by cheapest first
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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 Thursday when prices can be found for as low as $394. 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 $509. 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 $417 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 $454 per ticket.

When to book flights from Islip, New York to St. Louis

Are you open to changing your travel dates? Check out the ideal times to fly from Islip, New York to St. Louis according to our flight data. Find out which month and days have the cheapest flights.
Estimated round-trip price

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

Best Price Found

$428

Fastest flight time

6h 40m

Direct flights

None
The best one-way flight to St. Louis from Islip, New York in the past 72 hours is $428. The best round-trip flight deal from Islip, New York to St. Louis found on momondo in the last 72 hours is $400.
The fastest flight from Islip, New York to St. Louis takes 6h 40m
There are no direct flights from Islip, New York to St. Louis. There are no popular flight routes from Islip, New York to St. Louis.
Search flight deals

Frequently asked questions about flying 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 6h 40m.

  • 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?

  • 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?

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
SouthwestPriceFrom $214Free CancellationRating
7.9
4,213 reviews
Search Southwest flights

Traveling to a place near St. Louis?

Book flights to St. Louis if you plan to visit one of these locations
St. Charles
Fairview Heights
Chesterfield
Maryland Heights
St. Peters
Alton
Collinsville
Florissant
Farmington
Hermann
Clayton
Festus
Fenton
Edwardsville
O'Fallon
Eureka
Wentzville
Litchfield
Grafton
Waterloo

Why 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.

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