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Cheap flights from St. Louis to Islip (STL - ISP) from $125

This is the cheapest one-way flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 6/18. 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.
STL — ISP
Jun 11 — Jun 181
From?
To?
Tue 6/11
Tue 6/18
1 adult, Economy
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How far in advance should I book a flight from St. Louis to Islip, New York?

When searching for a good deal, it’s best to be prepared for potential fluctuations in price. We recommend booking at least 58 days in advance, which can save you up to 177% on flights from St. Louis to Islip, New York compared to booking the week you need them. Waiting 58 days out may not be for everyone, so we have options available for flights within the next two weeks, with the lowest price starting at $290. For sooner than that we have options available in the next 3 days from $562.

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

Due to multiple factors, expect to potentially pay more when booking in June. For low rates, September can be a great choice for travel to Islip, New York. Flights to Islip, New York from St. Louis in September are about $309 on average during September, but can be found for as low as $129.

What is the cheapest time of day to fly from STL to ISP?

When flying from St. Louis to Islip, New York, the time of day you decide to fly out makes little to no difference towards the overall price you’ll pay on tickets.

Cheap St. Louis to Islip flights in June & July 2024

Find cheap flight options from St. Louis to Islip specifically for the months of June and July 2024. Explore affordable fares based on user searches. Over the last 7 days, Cheapflights users made 3,050,429 searches. Prices were last updated on June 6, 2024.
Thu 7/187:33 pmSTL - ISP
1 stop11h 25mFrontier
Sun 7/2110:22 pmISP - STL
1 stop11h 21mFrontier
Deal found 6/5$220
Thu 7/257:33 pmSTL - ISP
1 stop11h 25mFrontier
Tue 7/309:43 pmISP - STL
1 stop12h 00mFrontier
Deal found 6/6$248
Thu 7/117:33 pmSTL - ISP
1 stop11h 25mFrontier
Tue 7/169:43 pmISP - STL
1 stop12h 00mFrontier
Deal found 6/4$339
Thu 7/47:29 pmSTL - ISP
1 stop11h 29mFrontier
Sun 7/710:22 pmISP - STL
1 stop11h 21mFrontier
Deal found 6/5$358
Sat 6/2212:13 pmSTL - ISP
1 stop18h 27mFrontier
Sun 6/2310:23 pmISP - STL
1 stop19h 51mFrontier
Deal found 6/5$432

St. Louis to Islip 2024 flight deals

Discover exclusive flight deals for travel between St. Louis and Islip in 2024. Find excellent offers based on user searches. Over the last 7 days, Cheapflights users made 3,050,429 searches. Data last updated June 6, 2024.
Thu 7/187:33 pmSTL - ISP
1 stop11h 25mFrontier
Sun 7/2110:22 pmISP - STL
1 stop11h 21mFrontier
Deal found 6/5$220
Fri 8/27:33 pmSTL - ISP
1 stop12h 05mFrontier
Sun 8/410:22 pmISP - STL
1 stop11h 21mFrontier
Deal found 6/6$246
Thu 7/257:33 pmSTL - ISP
1 stop11h 25mFrontier
Tue 7/309:43 pmISP - STL
1 stop12h 00mFrontier
Deal found 6/6$248
Fri 8/236:42 pmSTL - ISP
1 stop12h 44mFrontier
Mon 8/2610:00 amISP - STL
1 stop11h 20mFrontier
Deal found 6/4$249
Thu 7/117:33 pmSTL - ISP
1 stop11h 25mFrontier
Tue 7/169:43 pmISP - STL
1 stop12h 00mFrontier
Deal found 6/4$339
Thu 7/47:29 pmSTL - ISP
1 stop11h 29mFrontier
Sun 7/710:22 pmISP - STL
1 stop11h 21mFrontier
Deal found 6/5$358
Sat 6/2212:13 pmSTL - ISP
1 stop18h 27mFrontier
Sun 6/2310:23 pmISP - STL
1 stop19h 51mFrontier
Deal found 6/5$432

One-way flights to Islip from St. Louis

Search for one-way flight options from St. Louis to Islip. Find affordable one-way fares based on user searches. Compare prices and availability to plan your one-way journey according to your preferred dates and budget. Over the last 7 days, Cheapflights users made 3,050,429 searches. Data last updated June 6, 2024.
Tue 6/187:44 pmSTL - ISP
1 stop10h 56mFrontier
Deal found 6/5$125
Tue 6/117:44 pmSTL - ISP
1 stop10h 56mFrontier
Deal found 6/5$155
Tue 7/167:33 pmSTL - ISP
1 stop11h 25mFrontier
Deal found 6/5$201

Find flights from St. Louis to Islip within your budget

Customize your flight search to find flights from St. Louis to Islip that fit within your specific budget. Explore options based on user searches and filter the results based on your desired price range. Find flights that match your budget for a cost-effective journey. Over the last 7 days, Cheapflights users made 3,050,429 searches. Data last updated June 6, 2024.

Fly from

Any airport

Fly to

Any airport

Budget

$220 - $432

Route

Depart

Return

Price

Lambert-St LouisIslip Long Island

STL - ISP

STLISP

Lambert-St Louis

Thu 7/18

1 stop11h 25m

Islip Long Island

Sun 7/21

1 stop11h 21m

$220

Lambert-St LouisIslip Long Island

STL - ISP

STLISP

Lambert-St Louis

Fri 8/23

1 stop12h 44m

Islip Long Island

Mon 8/26

1 stop11h 20m

$249

Lambert-St LouisIslip Long Island

STL - ISP

STLISP

Lambert-St Louis

Thu 7/11

1 stop11h 25m

Islip Long Island

Tue 7/16

1 stop12h 00m

$339

Lambert-St LouisIslip Long Island

STL - ISP

STLISP

Lambert-St Louis

Thu 7/4

1 stop11h 29m

Islip Long Island

Sun 7/7

1 stop11h 21m

$358

Lambert-St LouisIslip Long Island

STL - ISP

STLISP

Lambert-St Louis

Sat 6/22

1 stop18h 27m

Islip Long Island

Sun 6/23

1 stop19h 51m

$432

Flights are sorted by cheapest first

Deals found on 6/5

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

Use this chart to determine the cheapest time to fly round-trip from St. Louis to Islip. Price data was last updated on June 2, 2024.
Morning
Noon
Afternoon
Evening
All times are departure.
Travelers seeking maximum savings on their St. Louis to Islip, New York flight should consider departing on Saturday evenings when fares are most often at their lowest. Saturday evenings flights should be avoided if possible as fares are typically the most expensive at this time.
Search Deals

Best time to book a flight from St. Louis to Islip

Have a flexible travel schedule? Discover the best time to fly to Islip from St. Louis with our price prediction graph.
Estimated round-trip price
Rates are based on past data. Find the cheapest month and day to book your flight based on your travel requirements, then search for cheap deals.

Reviews of airlines servicing Islip

Get insights into the airlines that provide service to Islip. Read reviews, discover amenities, and learn about the overall travel experience offered by airlines. Use this information to make informed decisions when choosing an airline for your flight to Islip. Reviews last updated June 6, 2024.
Frontier
6.2
Okay
3,985 reviews

Overall

6.2

Boarding

6.5

Crew

7.0

Comfort

5.8

Entertainment

4.9

Food

5.1

Reviews

1 / 10

I'd thought there would be a complimentary drink atleast.

Frontier
6.2
Okay
3,985 reviews
Frontier
6.2
Okay
3,985 reviews

Overall

6.2

Boarding

6.5

Crew

7.0

Comfort

5.8

Entertainment

4.9

Food

5.1

Reviews

1 / 10

I'd thought there would be a complimentary drink atleast.

Related info for your journey

Find useful and relevant information for your journey from St. Louis to Islip. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.

  • Can I find flights from St. Louis to Islip, New York for under $300 on Cheapflights?

    Yes, there are multiple flights from St. Louis to Islip, New York for under $300. The cheapest flight booked recently is on Frontier for just $220, but on average you can expect to pay $319.

  • What does STL to ISP mean?

    Lambert-St Louis Airport is STL and Islip Long Island Airport is ISP. These codes are created by the International Air Transport Association (IATA) and airlines use them to identify the departing and arrival airports in the flight routes they service.

  • Can I find deals for flights from St. Louis to Islip that include extra baggage allowance?

    The amount of baggage you can bring on your St. Louis to Islip flight depends on the airline and the type of fare you've chosen. After entering your flight details, you'll be able to view the specific baggage policies for each deal in the search results. Keep in mind that certain deals may offer additional baggage allowance.

  • Can I find deals on flights from St. Louis to Islip with specific airlines?

    Yes, Cheapflights allows you to browse and filter St. Louis to Islip flight deals by airline. After entering your origin and destination, use the available filters to view flights offered by airlines.

  • Can I find deals for flights from St. Louis to Islip that include hotel bookings?

    Yes. In addition to deals on St. Louis to Islip flights, Cheapflights offers vacation packages that include both flights and hotel.

  • How can I find direct flights from St. Louis to Islip?

    After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from St. Louis to Islip.

  • Can I find deals for business class flights from St. Louis to Islip?

    Yes. Cheapflights offers flight deals from St. Louis to Islip by cabin class. In addition to browsing deals, you can also filter by cabin class on the search results page after making a search.

  • Can I find deals for flights from St. Louis to Islip that allow pets onboard?

    Many airlines flying from St. Louis to Islip offer the option to travel with pets. After selecting a flight deal, you can find more information about the airline's pet policy on their official website or by contacting the airline directly. Please note that additional fees and restrictions may apply.

  • Can I find deals on last-minute flights from St. Louis to Islip?

    Yes, you can often find last-minute deals on St. Louis to Islip flights on Cheapflights. However, these deals can vary and may not always be available. We recommend checking back frequently or signing up for price alerts for the most up-to-date deals.

  • How recently were the St. Louis to Islip, New York flight deals updated?

    The St. Louis to Islip, New York flight deals you see on this page were last updated on 6/6.

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

    Currently, December is the cheapest month in which you can book a flight from St. Louis to Islip, New York (average of $78). Flying from St. Louis to Islip, New York in February is currently the most expensive (average of $151). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

See more FAQs

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Search flights from St. Louis to Islip by cabin class

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