--- title: "Islip to St. Louis cheap flights from $116 (ISP to STL) - Expedia" description: "Book cheap Flights from Islip (ISP) to St. Louis (STL) start at $116 for one-way and $371 for round trip. Earn your airline miles on top of our rewards!" canonical: "https://www.expedia.com/lp/flights/isp/stl/islip-to-st-louis" language: en-US market: US currency: USD prices_as_of: 2026-11-14T04:26:35Z --- # $116 Cheap Flights from Islip (ISP) to St. Louis (STL) ![A city skyline with a prominent arch bridge at sunset.](https://images.trvl-media.com/place/5002323/199e2ff7-9ba1-40d2-987c-00d8170be611.jpg?impolicy=fcrop&w=1200&h=500&q=medium) [View $116 flight on Sat, Feb 27, 2027](https://www.expedia.com/Flights-Search?leg1=from:ISP,to:STL,departure:2/27/2027TANYT&trip=oneway&passengers=adults:1,children:0,infantinlap:N&mode=search&pageId=0&flp=mdl:flights-flex-module,price:115.59&airProductToken=AQpeCi0IxnISBDM5NDEYyHwgzHAom7CmAzDWsaYDOFJAAFgBagNFQ09yB1IyMU9YUDQKLQjGchIEMjYzNRjMcCDyXCiKtaYDMKy2pgM4UkABWAFqA0VDT3IHUjIxT1hQNBIKCAEQARgBKgJGORgBIgQIARABKAIoAygEMAE) ## Popular airlines from MacArthur Airport (ISP) to St. Louis Lambert Intl. Airport (STL) [Frontier Airlines](https://www.expedia.com/Flights-Search?leg1=from:ISP,to:STL,departure:11/28/2026TANYT&leg2=from:STL,to:ISP,departure:12/5/2026TANYT&trip=roundtrip&passengers=adults:1,children:0,infantinlap:N&mode=search&pageId=0&filters=[{"preferredAirlineFilterValue":{"carrierCode":"F9"}}]) [Southwest Airlines](https://www.expedia.com/Flights-Search?leg1=from:ISP,to:STL,departure:11/28/2026TANYT&leg2=from:STL,to:ISP,departure:12/5/2026TANYT&trip=roundtrip&passengers=adults:1,children:0,infantinlap:N&mode=search&pageId=0&filters=[{"preferredAirlineFilterValue":{"carrierCode":"WN"}}]) ### Be in the know Get alerts if flight prices drop or rise\* ### Book smarter Save up to 30% on select hotels after you book a flight\* ### Earn twice Earn your airline miles on top of our OneKeyCash [Learn about One Key](https://www.expedia.com/welcome-one-key) Find the cheapest flights on Expedia from (ISP) to (STL). Flight ticket prices change frequently based on availability and demand. We send price‑drop alerts to make air travel simple and flexible. The lowest one-way fare found on Expedia for this route in the past 7 days starts at $116 for travel on February 27, 2027. ## Cheap Flights from Islip to St. Louis (ISP-STL) Prices were available within the past 7 days and start at $116 for one-way flights and $371 for roundtrip, for the period specified. Prices and availability are subject to change. All deals One way Roundtrip [Select Southwest Airlines flight, departing Tue, Dec 8 from Islip to St. Louis, returning Wed, Dec 9, priced at $371 Found 1 day ago](https://www.expedia.com/Flights-Search?leg1=from:ISP,to:STL,departure:12/8/2026TANYT&leg2=from:STL,to:ISP,departure:12/9/2026TANYT&trip=roundtrip&passengers=adults:1,children:0,infantinlap:N&mode=search&pageId=0&flp=mdl:flights-flex-module,price:370.41&airProductToken=AQpgCi4I15wBEgQxMDM0GMh8IMxwKK2jnwMw3KSfAzhEQABYAWoDV0dBcgdEWEFWUzJGCi4I15wBEgQyODc1GMxwIPJcKImlnwMwrqafAzhEQAFYAWoDV0dBcgdEWEFWUzJGCmAKLgjXnAESBDQxMjQY8lwgwUUok6qfAzCGq58DOERAAFgBagNXR0FyB0RYQVZTMkYKLgjXnAESBDEwMzQYwUUgyHwo1a2fAzCbrp8DOERAAVgBagNXR0FyB0RYQVZTMkYSCggBEAEYASoCV04YASIECAEQASgCKAMoBDAB) Tue, Dec 8 - Wed, Dec 9 · ISP · STL · Roundtrip [Select Southwest Airlines flight, departing Wed, Jan 6 from Islip to St. Louis, returning Wed, Jan 13, priced at $373 Found 4 days ago](https://www.expedia.com/Flights-Search?leg1=from:ISP,to:STL,departure:1/6/2027TANYT&leg2=from:STL,to:ISP,departure:1/13/2027TANYT&trip=roundtrip&passengers=adults:1,children:0,infantinlap:N&mode=search&pageId=0&flp=mdl:flights-flex-module,price:372.40&airProductToken=AQpgCi4I15wBEgQxOTkxGMh8IMFFKOnooQMwuemhAzhEQABYAWoDV0dBcgdETEFXVjJGCi4I15wBEgQ0OTkzGMFFIPJcKInqoQMwpOuhAzhEQAFYAWoDV0dBcgdETEFXVjJGEgoIARABGAEqAldOGAEiBAgBEAEoAigDKAQwAQ) Wed, Jan 6 - Wed, Jan 13 · ISP · STL · Roundtrip [Select Southwest Airlines flight, departing Tue, Dec 8 from Islip to St. Louis, returning Wed, Dec 9, priced at $376 Found 1 day ago](https://www.expedia.com/Flights-Search?leg1=from:ISP,to:STL,departure:12/8/2026TANYT&leg2=from:STL,to:ISP,departure:12/9/2026TANYT&trip=roundtrip&passengers=adults:1,children:0,infantinlap:N&mode=search&pageId=0&flp=mdl:flights-flex-module,price:375.71&airProductToken=AQpgCi4I15wBEgQyMjA5GMh8IMFFKJqhnwMw5aGfAzhEQABYAWoDV0dBcgdEWEFWUzJGCi4I15wBEgQxMzkwGMFFIPJcKI6lnwMwn6afAzhEQAFYAWoDV0dBcgdEWEFWUzJGCpIBCi8I15wBEgQzNjY3GPJcIMGTASiorZ8DML6unwM4REAAWAFqA1dHQXIHRFhBVlMyRgovCNecARIEMTk1NxjBkwEgwUUo666fAzDPr58DOERAAVgBagNXR0FyB0RYQVZTMkYKLgjXnAESBDEwMzUYwUUgyHwon7CfAzDlsJ8DOERAAVgBagNXR0FyB0RYQVZTMkYSCggBEAEYASoCV04YASIECAEQASgCKAMoBDAB) Tue, Dec 8 - Wed, Dec 9 · ISP · STL · Roundtrip [Select Southwest Airlines flight, departing Wed, Jan 6 from Islip to St. Louis, returning Wed, Jan 13, priced at $378 Found 4 days ago](https://www.expedia.com/Flights-Search?leg1=from:ISP,to:STL,departure:1/6/2027TANYT&leg2=from:STL,to:ISP,departure:1/13/2027TANYT&trip=roundtrip&passengers=adults:1,children:0,infantinlap:N&mode=search&pageId=0&flp=mdl:flights-flex-module,price:377.71&airProductToken=AQpgCi4I15wBEgQxOTkxGMh8IMFFKOnooQMwuemhAzhEQABYAWoDV0dBcgdETEFXVjJGCi4I15wBEgQ0OTkzGMFFIPJcKInqoQMwpOuhAzhEQAFYAWoDV0dBcgdETEFXVjJGCpABCi8I15wBEgQ0MTIzGPJcIMejASjQs6IDMNK0ogM4REAAWAFqA1dHQXIHRExBV1YyRgouCNecARIDNDc4GMejASDBRSiLtqIDML-3ogM4REABWAFqA1dHQXIHRExBV1YyRgotCNecARIDODk0GMFFIMh8KPC5ogMwu7qiAzhEQAFYAWoDV0dBcgdETEFXVjJGEgoIARABGAEqAldOGAEiBAgBEAEoAigDKAQwAQ) Wed, Jan 6 - Wed, Jan 13 · ISP · STL · Roundtrip [Select Southwest Airlines flight, departing Tue, Dec 8 from Islip to St. Louis, returning Wed, Dec 9, priced at $382 Found 1 day ago](https://www.expedia.com/Flights-Search?leg1=from:ISP,to:STL,departure:12/8/2026TANYT&leg2=from:STL,to:ISP,departure:12/9/2026TANYT&trip=roundtrip&passengers=adults:1,children:0,infantinlap:N&mode=search&pageId=0&flp=mdl:flights-flex-module,price:381.01&airProductToken=AQpgCi4I15wBEgQyMjA5GMh8IMFFKJqhnwMw5aGfAzhEQABYAWoDV0dBcgdEWEFWUzJGCi4I15wBEgQxMTExGMFFIPJcKJ6jnwMw9aSfAzhEQAFYAWoDV0dBcgdEWEFWUzJGCpIBCi8I15wBEgQzNjY3GPJcIMGTASiorZ8DML6unwM4REAAWAFqA1dHQXIHRFhBVlMyRgovCNecARIEMTk1NxjBkwEgwUUo666fAzDPr58DOERAAVgBagNXR0FyB0RYQVZTMkYKLgjXnAESBDEwMzUYwUUgyHwon7CfAzDlsJ8DOERAAVgBagNXR0FyB0RYQVZTMkYSCggBEAEYASoCV04YASIECAEQASgCKAMoBDAB) Tue, Dec 8 - Wed, Dec 9 · ISP · STL · Roundtrip [Select Southwest Airlines flight, departing Wed, Jan 6 from Islip to St. Louis, returning Wed, Jan 13, priced at $384 Found 4 days ago](https://www.expedia.com/Flights-Search?leg1=from:ISP,to:STL,departure:1/6/2027TANYT&leg2=from:STL,to:ISP,departure:1/13/2027TANYT&trip=roundtrip&passengers=adults:1,children:0,infantinlap:N&mode=search&pageId=0&flp=mdl:flights-flex-module,price:383.01&airProductToken=AQpfCi0I15wBEgMyMjYYyHwgwUUouuehAzCK6KEDOERAAFgBagNXR0FyB0RMQVdWMkYKLgjXnAESBDQ5OTMYwUUg8lwoieqhAzCk66EDOERAAVgBagNXR0FyB0RMQVdWMkYKjgEKLgjXnAESBDM3NjMY8lwgoQMovrSiAzCEtaIDOERAAFgBagNXR0FyB0RMQVdWMkYKLQjXnAESAzQ5MhihAyDBRSjUtaIDMKu3ogM4REABWAFqA1dHQXIHRExBV1YyRgotCNecARIDODk0GMFFIMh8KPC5ogMwu7qiAzhEQAFYAWoDV0dBcgdETEFXVjJGEgoIARABGAEqAldOGAEiBAgBEAEoAigDKAQwAQ) Wed, Jan 6 - Wed, Jan 13 · ISP · STL · Roundtrip [Select Southwest Airlines flight, departing Wed, Jan 6 from Islip to St. Louis, returning Wed, Jan 13, priced at $388 Found 4 days ago](https://www.expedia.com/Flights-Search?leg1=from:ISP,to:STL,departure:1/6/2027TANYT&leg2=from:STL,to:ISP,departure:1/13/2027TANYT&trip=roundtrip&passengers=adults:1,children:0,infantinlap:N&mode=search&pageId=0&flp=mdl:flights-flex-module,price:387.40&airProductToken=AQpeCi0I15wBEgM4NDkYyHwgwUUopeShAzD%5F5KEDOEpAAFgBagNXR0FyB0pMQVZQMkYKLQjXnAESAzQ0MhjBRSDyXCiD56EDMJnooQM4SkABWAFqA1dHQXIHSkxBVlAyRgpeCi4I15wBEgQ0MTE5GPJcIMFFKOmzogMw5rSiAzhEQABYAWoDV0dBcgdETEFXVjJGCiwI15wBEgI3NhjBRSDIfCiXt6IDMN23ogM4REABWAFqA1dHQXIHRExBV1YyRhIKCAEQARgBKgJXThgBIgQIARABKAIoAygEMAE) Wed, Jan 6 - Wed, Jan 13 · ISP · STL · Roundtrip [Select Southwest Airlines flight, departing Wed, Jan 6 from Islip to St. Louis, returning Wed, Jan 13, priced at $389 Found 4 days ago](https://www.expedia.com/Flights-Search?leg1=from:ISP,to:STL,departure:1/6/2027TANYT&leg2=from:STL,to:ISP,departure:1/13/2027TANYT&trip=roundtrip&passengers=adults:1,children:0,infantinlap:N&mode=search&pageId=0&flp=mdl:flights-flex-module,price:388.31&airProductToken=AQqQAQouCNecARIEMTk5MRjIfCDBRSjp6KEDMLnpoQM4REAAWAFqA1dHQXIHRExBV1YyRgouCNecARIEMTcwOBjBRSDMcCj86qEDMJLsoQM4REABWAFqA1dHQXIHRExBV1YyRgouCNecARIEMjYwORjMcCDyXCjZ76EDMPnwoQM4REABWAFqA1dHQXIHRExBV1YyRgqPAQovCNecARIEMTMwNBjyXCDssAEo1bOiAzCbtKIDOERAAFgBagNXR0FyB0RMQVdWMkYKLgjXnAESAzMwORjssAEgwUUo17SiAzC4tqIDOERAAVgBagNXR0FyB0RMQVdWMkYKLAjXnAESAjc2GMFFIMh8KJe3ogMw3beiAzhEQAFYAWoDV0dBcgdETEFXVjJGEgoIARABGAEqAldOGAEiBAgBEAEoAigDKAQwAQ) Wed, Jan 6 - Wed, Jan 13 · ISP · STL · Roundtrip [Select Southwest Airlines flight, departing Tue, Dec 8 from Islip to St. Louis, returning Wed, Dec 9, priced at $392 Found 1 day ago](https://www.expedia.com/Flights-Search?leg1=from:ISP,to:STL,departure:12/8/2026TANYT&leg2=from:STL,to:ISP,departure:12/9/2026TANYT&trip=roundtrip&passengers=adults:1,children:0,infantinlap:N&mode=search&pageId=0&flp=mdl:flights-flex-module,price:391.40&airProductToken=AQpgCi4I15wBEgQxMDM0GMh8IMxwKK2jnwMw3KSfAzhEQABYAWoDV0dBcgdEWEFWUzJGCi4I15wBEgQyODc1GMxwIPJcKImlnwMwrqafAzhEQAFYAWoDV0dBcgdEWEFWUzJGCmAKLgjXnAESBDQxMjQY8lwgwUUok6qfAzCGq58DOEpAAFgBagNXR0FyB0pMQVZQMkYKLgjXnAESBDExMDAYwUUgyHwozKufAzCNrJ8DOEpAAVgBagNXR0FyB0pMQVZQMkYSCggBEAEYASoCV04YASIECAEQASgCKAMoBDAB) Tue, Dec 8 - Wed, Dec 9 · ISP · STL · Roundtrip [Select Frontier Airlines flight, departing Sun, Nov 22 from Islip to St. Louis, returning Thu, Nov 26, priced at $1,317 Found 8 hours ago](https://www.expedia.com/Flights-Search?leg1=from:ISP,to:STL,departure:11/22/2026TANYT&leg2=from:STL,to:ISP,departure:11/26/2026TANYT&trip=roundtrip&passengers=adults:1,children:0,infantinlap:N&mode=search&pageId=0&flp=mdl:flights-flex-module,price:1316.62&airProductToken=AQpeCi0IxnISBDIxNDkYyHwgzHAolO-dAzDM8J0DOFVAAFgBagNFQ09yB1UwN1BYUzYKLQjGchIEMTYzMRjMcCDyXCjl8Z0DMIfznQM4TEABWAFqA0VDT3IHTDA3UFhTOAqPAQouCMZyEgQzMTA3GPJcIIuQASjznJ4DMNOengM4TkAAWAFqA0VDT3IHTjAwUlhTNQouCMZyEgQxNzI4GIuQASDMcCj9oJ4DMImjngM4TkABWAFqA0VDT3IHTjAwUlhTNQotCMZyEgQxMjM4GMxwIMh8KOKlngMw%5FaaeAzhHQAFYAWoDRUNPcgdHMTRQWFM2EgoIARABGAEqAkY5GAEiBAgBEAEoAigDKAQwAQ) Sun, Nov 22 - Thu, Nov 26 · ISP · STL · Roundtrip ## Book with confidence ### Islip to St. Louis Flights #### The cheapest times to fly from Islip to St. Louis On average, Thursday can be the cheapest time to fly, according to data from the Airlines Reporting Corporation (ARC), one of the world's biggest databases for global airline sales. The data reveals that you could save up to 16% by flying on a Thursday—the cheapest day to travel on average—instead of a Sunday—the most expensive. Some of the most affordable flights from Islip to St. Louis are during the month of December. You can find some of the cheapest flights from Islip to St. Louis with Expedia's search tool and vast selection of airlines. #### The best time to book a flight from Islip to St. Louis Sunday is one of the best days to book for cheap flights from Islip to St. Louis: Tickets reserved on a Sunday cost between 6% and 13% less than those reserved on a Friday, according to ARC data. The data also suggests booking early can also lead to cheaper airfares. You could save 24% by buying your tickets for domestic flights at least a month in advance and 10% by booking international flights 2 months in advance. #### How to find cheap round-trip tickets from Islip to St. Louis Being flexible with your dates and using Expedia's Price Drop Protection and Price Tracking features are some of the best ways of finding a cheap ticket from Islip to St. Louis in 2026\. You can also book with separate airlines for your outbound and return journeys, from $116 one-way. Expedia also offers Price Drop Protection, so if the cost of your airfare goes down after booking, you'll receive a credit for the difference\*. This is available for a small fee, and is free to One Key Gold and Platinum tier members. Expedia's Price Tracking feature means you can stay on top of airfares without manually checking every day. It sends you automated price alerts for cheap Islip to St. Louis flights and uses historical data to indicate when the best time to book is. Download Expedia's free app to activate this handy tool in a few easy taps. You could also save big by booking one of Expedia's [vacation packages](https://www.expedia.com/package-deals). Bundling together your Islip to St. Louis airfare with your accommodations and car rental is often cheaper than booking everything separately. There’s also One Key, Expedia's generous rewards program. Join for free and you could earn One Key cash on most bookings to save on future adventures. *\*Terms apply.* *Disclaimer: ARC The statistics are based on average round-trip ticket prices between January and August 2023\. The percentages you see are averages.* ## Frequently Asked Questions ### How much does a flight from Islip, NY (ISP-MacArthur) to St. Louis, MO (STL-Lambert-St. Louis Intl.) cost? You can find cheap one-way flights from $116 and cheap return flights $371 Islip, NY (ISP-MacArthur) to St. Louis, MO (STL-Lambert-St. Louis Intl.) with Expedia. One-way flights usually range from $284 to $1482, and return flights typically cost between $306 and $1478\. Flight prices vary based on the month and day of the week you want to travel, as well as the airline and how far in advance you book your ticket. Filter your search on Expedia by "Price (lowest to highest)" to see the cheapest fares first, and use the Price Tracking tool to receive alerts when Islip, NY (ISP-MacArthur) to St. Louis, MO (STL-Lambert-St. Louis Intl.) ticket fares go up or down. *\*Typical price ranges based on flights available on Expedia in the last year. Prices include multi-airline options.* ### What is the cheapest month to fly from Islip, NY (ISP-MacArthur) to St. Louis, MO (STL-Lambert-St. Louis Intl.)? The cheapest month to fly from ISP to STL is December when demand is low. Traveling in off-peak or shoulder months is usually a good way to secure cheap tickets, just remember to avoid flying during holidays if you're able to. Use the calendar view in your search to see which months have low fares on this route. ### Which airlines fly direct from Islip, NY (ISP-MacArthur) to St. Louis, MO (STL-Lambert-St. Louis Intl.)? Enter ISP to STL and your travel dates, then apply the 'Nonstop' filter to see only direct flights. ### What is the cheapest airline that flies from Islip, NY (ISP-MacArthur) to St. Louis, MO (STL-Lambert-St. Louis Intl.)? Frontier Airlines is one of the cheapest airlines offering connecting flights from MacArthur (ISP) to Lambert-St. Louis Intl. (STL), with round-trip tickets starting from around $342\. This option allows you to travel conveniently while keeping your budget in check. Use Expedia's search tool to compare the prices and schedules of airlines that fly this route to find the best option for your plans and budget. *\*Prices based on flights available on Expedia in the last year.* ### How do I find cheap flights from Islip, NY (ISP-MacArthur) to St. Louis, MO (STL-Lambert-St. Louis Intl.)? To find a cheap flight from Islip, NY (ISP-MacArthur) to St. Louis, MO (STL-Lambert-St. Louis Intl.), be flexible with your dates. Traveling outside of peak vacation months and booking a mid-week flight can help you save. Early morning and late night flights are often more affordable, too. Expedia allows you to compare flight times, airlines and routes all in one place to find low fares. You can also set up [Price Tracking](https://www.expedia.com/why/price-tracking) and receive alerts when fares go up or down. ### What is the best time to fly from Islip, NY (ISP-MacArthur) to St. Louis, MO (STL-Lambert-St. Louis Intl.)? The best time to fly is usually mid-week (Tuesday or Wednesday) and during early morning hours as flights tend to be cheaper, less crowded, and generally more on-time. Avoid major holidays and peak vacation seasons for smoother travel. Combining off-peak days and hours often gives the best combination of cost, comfort, and convenience. ### What is the earliest flight from Islip, NY (ISP-MacArthur) to St. Louis, MO (STL-Lambert-St. Louis Intl.)? The earliest flight from Islip, NY (ISP) to St. Louis, MO (STL) typically departs at around 5:00 AM local time, operated by Southwest Airlines. This seasonal service is available in April and May, allowing you to maximize your time in St. Louis. To compare early flights on Expedia, select the "Early Morning" and "Morning" filters in your search. ### What are the most popular departure times for flights from Islip, NY (ISP-MacArthur) to St. Louis, MO (STL-Lambert-St. Louis Intl.)? The most popular departure times for flights from Islip, NY (ISP-MacArthur) to St. Louis, MO (STL-Lambert-St. Louis Intl.) are in the late afternoon to early evening, from 3pm to 6pm. About 32% of passengers prefer this time window. Many major carriers, including Southwest Airlines, offer flights during this window. This timing works well because it allows you to travel after a productive day. ### How long does it take to fly from Islip, NY (ISP-MacArthur) to St. Louis, MO (STL-Lambert-St. Louis Intl.)? Flights from ISP to STL with one stop typically take around 8 hours, covering approximately 926 miles. Keep in mind that actual flight times can vary due to wind patterns, weather, and air traffic. ### Can you fly business or first class from Islip, NY (ISP-MacArthur) to St. Louis, MO (STL-Lambert-St. Louis Intl.)? Select the "Business class" and "First class" filters when looking for ISP to STL flights on Expedia. This is the easiest way to compare prices, routes and flight times for your trip. ### How do I earn miles on a Islip, NY (ISP-MacArthur) to St. Louis, MO (STL-Lambert-St. Louis Intl.) flight with Expedia? It's easy to earn miles on a Islip, NY (ISP-MacArthur) to St. Louis, MO (STL-Lambert-St. Louis Intl.) flight when you book with Expedia. Before you confirm your booking, simply select your frequent flyer program and enter your program number. As a member of [One Key™](https://www.expedia.com/welcome-one-key), you can also earn OneKeyCash™\* on top of your airline miles when you book with Expedia. \*Excludes taxes and fees. OneKeyCash is not redeemable for cash and can only be used on Expedia and other participating brands. ### What airports do you fly into for St. Louis from MacArthur (ISP)? From MacArthur (ISP), you can fly into Lambert-St. Louis Intl. (STL) to reach St. Louis. Some flights may connect through major hubs like Logan Intl. (BOS), Baltimore Washington Intl. Thurgood Marshall (BWI), Orlando Intl. (MCO) before reaching St. Louis. Compare routes and airports on Expedia to find the best flight options for your travel plans. ### Is it cheaper to buy a plane ticket from Islip, NY (ISP-MacArthur) to St. Louis, MO (STL-Lambert-St. Louis Intl.) at the last minute? Typically, booking a last minute flight from Islip, NY (ISP-MacArthur) to St. Louis, MO (STL-Lambert-St. Louis Intl.) will be more expensive than booking in advance. As the departure date approaches, there are usually fewer seats available which can drive up the cost. However, if there's some wiggle room with your travel dates and times, you could bag a cheap last-minute fare. ### Is it cheaper to book a Islip, NY (ISP-MacArthur) to St. Louis, MO (STL-Lambert-St. Louis Intl.) flight and hotel package? Securing a Islip, NY (ISP-MacArthur) to St. Louis, MO (STL-Lambert-St. Louis Intl.) [St Louis Vacation Packages](https://www.expedia.com/st-louis.d178309.destination-travel-guides) is usually cheaper than booking separately. With Expedia, you can enjoy the ease of organizing your travels all in one place. Select from our extensive range of stays and then add flights, activities and car rentals to your booking. Bundle everything together, and you could save hundreds of dollars. ### Can I cancel or change the date of my flight from Islip, NY (ISP-MacArthur) to St. Louis, MO (STL-Lambert-St. Louis Intl.)? If you booked your Islip, NY (ISP-MacArthur) to St. Louis, MO (STL-Lambert-St. Louis Intl.) flight within the last 24 hours, you may be able to modify or cancel it without any fees. Depending on the airline and the type of ticket you have, additional charges may apply for changes beyond this timeframe. Airline policies and contact information can be found in [your itinerary](https://www.expedia.com/trips) or confirmation email. Or, head to our [Customer Service portal](https://www.expedia.com/helpcenter/) if you'd like more information. ## Travel information | Origin airport | MacArthur Airport | | ------------------- | ------------------------------------- | | Destination airport | St. Louis Lambert Intl. Airport | | Distance | 926 miles away | | Airlines serving | Frontier Airlines, Southwest Airlines | | Popular airline | Frontier Airlines | | Roundtrip price | $371 | ## Explore a world of travel with Expedia - [Flights](?equalTargetTab=tab-0) - [Flights from Birmingham (BHM) to St. Louis (STL)](https://www.expedia.com/lp/flights/bhm/stl/birmingham-to-st-louis) - [Flights from Albany (ALB) to St. Louis (STL)](https://www.expedia.com/lp/flights/alb/stl/albany-to-st-louis) - [Flights from Baltimore (BWI) to St. Louis (STL)](https://www.expedia.com/lp/flights/bwi/stl/baltimore-to-st-louis) - [Flights from San Diego (SAN) to St. Louis (STL)](https://www.expedia.com/lp/flights/san/stl/san-diego-to-st-louis) - [Flights from Detroit (DTW) to St. Louis (STL)](https://www.expedia.com/lp/flights/dtw/stl/detroit-to-st-louis) - [Flights from Fort Myers (RSW) to St. Louis (STL)](https://www.expedia.com/lp/flights/rsw/stl/fort-myers-to-st-louis) - [Flights from Sioux Falls (FSD) to St. Louis (STL)](https://www.expedia.com/lp/flights/fsd/stl/sioux-falls-to-st-louis) - [Flights from Kansas City (MCI) to St. Louis (STL)](https://www.expedia.com/lp/flights/mci/stl/kansas-city-to-st-louis) - [Flights from San Jose (SJC) to St. Louis (STL)](https://www.expedia.com/lp/flights/sjc/stl/san-jose-to-st-louis) - [Flights from Chicago (ORD) to St. Louis (STL)](https://www.expedia.com/lp/flights/ord/stl/chicago-to-st-louis) - [Flights from Rochester (ROC) to St. Louis (STL)](https://www.expedia.com/lp/flights/roc/stl/rochester-to-st-louis) - [Flights from Little Rock (LIT) to St. Louis (STL)](https://www.expedia.com/lp/flights/lit/stl/little-rock-to-st-louis) - [Flights from Sacramento (SMF) to St. Louis (STL)](https://www.expedia.com/lp/flights/smf/stl/sacramento-to-st-louis) - [Flights from Huntsville (HSV) to St. Louis (STL)](https://www.expedia.com/lp/flights/hsv/stl/huntsville-to-st-louis) - [Flights from Memphis (MEM) to St. Louis (STL)](https://www.expedia.com/lp/flights/mem/stl/memphis-to-st-louis) - [Flights from Papeete (PPT) to St. Louis (STL)](https://www.expedia.com/lp/flights/ppt/stl/papeete-to-st-louis) - [Flights from Wichita (ICT) to St. Louis (STL)](https://www.expedia.com/lp/flights/ict/stl/wichita-to-st-louis) - [Flights from New Orleans (MSY) to St. Louis (STL)](https://www.expedia.com/lp/flights/msy/stl/new-orleans-to-st-louis) - [Flights from Syracuse (SYR) to St. Louis (STL)](https://www.expedia.com/lp/flights/syr/stl/syracuse-to-st-louis) - [Flights from Omaha (OMA) to St. Louis (STL)](https://www.expedia.com/lp/flights/oma/stl/omaha-to-st-louis) - [Flights from Columbia (COU) to St. Louis (STL)](https://www.expedia.com/lp/flights/cou/stl/columbia-to-st-louis) - [Flights from Jonesboro (JBR) to St. Louis (STL)](https://www.expedia.com/lp/flights/jbr/stl/jonesboro-to-st-louis) - [Flights from Fort Lauderdale (FLL) to St. Louis (STL)](https://www.expedia.com/lp/flights/fll/stl/fort-lauderdale-to-st-louis) - [Flights from Providence (PVD) to St. Louis (STL)](https://www.expedia.com/lp/flights/pvd/stl/providence-to-st-louis) - [Flights from Raleigh (RDU) to St. Louis (STL)](https://www.expedia.com/lp/flights/rdu/stl/raleigh-to-st-louis) - [Flights from Tampa (TPA) to St. Louis (STL)](https://www.expedia.com/lp/flights/tpa/stl/tampa-to-st-louis) - [Flights from Minneapolis (MSP) to St. Louis (STL)](https://www.expedia.com/lp/flights/msp/stl/minneapolis-to-st-louis) - [Flights from Lexington (LEX) to St. Louis (STL)](https://www.expedia.com/lp/flights/lex/stl/lexington-to-st-louis) - [Flights from Grand Rapids (GRR) to St. Louis (STL)](https://www.expedia.com/lp/flights/grr/stl/grand-rapids-to-st-louis) - [Flights from Phoenix (PHX) to St. Louis (STL)](https://www.expedia.com/lp/flights/phx/stl/phoenix-to-st-louis) - [Flights from Madison (MSN) to St. Louis (STL)](https://www.expedia.com/lp/flights/msn/stl/madison-to-st-louis) - [Flights from Orlando (MCO) to St. Louis (STL)](https://www.expedia.com/lp/flights/mco/stl/orlando-to-st-louis) - [Flights from Norfolk (ORF) to St. Louis (STL)](https://www.expedia.com/lp/flights/orf/stl/norfolk-to-st-louis) - [Flights from Paris (CDG) to St. Louis (STL)](https://www.expedia.com/lp/flights/cdg/stl/paris-to-st-louis) - [Flights from Greenville (GSP) to St. Louis (STL)](https://www.expedia.com/lp/flights/gsp/stl/greenville-to-st-louis) - [Flights from Savannah (SAV) to St. Louis (STL)](https://www.expedia.com/lp/flights/sav/stl/savannah-to-st-louis) - [Flights from Nairobi (NBO) to St. Louis (STL)](https://www.expedia.com/lp/flights/nbo/stl/nairobi-to-st-louis) - [Flights from Washington (IAD) to St. Louis (STL)](https://www.expedia.com/lp/flights/iad/stl/washington-to-st-louis) - [Flights from Manila (MNL) to St. Louis (STL)](https://www.expedia.com/lp/flights/mnl/stl/manila-to-st-louis) - [Flights from Knoxville (TYS) to St. Louis (STL)](https://www.expedia.com/lp/flights/tys/stl/knoxville-to-st-louis) - [Flights from Jacksonville (JAX) to St. Louis (STL)](https://www.expedia.com/lp/flights/jax/stl/jacksonville-to-st-louis) - [Flights from Fayetteville (XNA) to St. Louis (STL)](https://www.expedia.com/lp/flights/xna/stl/fayetteville-to-st-louis) - [Flights from Branson (BKG) to St. Louis (STL)](https://www.expedia.com/lp/flights/bkg/stl/branson-to-st-louis) - [Flights from New York (JFK) to St. Louis (STL)](https://www.expedia.com/lp/flights/jfk/stl/new-york-to-st-louis) - [Flights from San Antonio (SAT) to St. Louis (STL)](https://www.expedia.com/lp/flights/sat/stl/san-antonio-to-st-louis) - [Flights from Washington (DCA) to St. Louis (STL)](https://www.expedia.com/lp/flights/dca/stl/washington-to-st-louis) - [Flights from Anchorage (ANC) to St. Louis (STL)](https://www.expedia.com/lp/flights/anc/stl/anchorage-to-st-louis) - [Flights from Boston (BOS) to St. Louis (STL)](https://www.expedia.com/lp/flights/bos/stl/boston-to-st-louis) - [Flights from Oklahoma City (OKC) to St. Louis (STL)](https://www.expedia.com/lp/flights/okc/stl/oklahoma-city-to-st-louis) - [Flights from Louisville (SDF) to St. Louis (STL)](https://www.expedia.com/lp/flights/sdf/stl/louisville-to-st-louis) - [Flights from Austin (AUS) to St. Louis (STL)](https://www.expedia.com/lp/flights/aus/stl/austin-to-st-louis) - [Flights from Buffalo (BUF) to St. Louis (STL)](https://www.expedia.com/lp/flights/buf/stl/buffalo-to-st-louis) - [Flights from Milwaukee (MKE) to St. Louis (STL)](https://www.expedia.com/lp/flights/mke/stl/milwaukee-to-st-louis) - [Flights from Charleston (CHS) to St. Louis (STL)](https://www.expedia.com/lp/flights/chs/stl/charleston-to-st-louis) - [Flights from Charlotte (CLT) to St. Louis (STL)](https://www.expedia.com/lp/flights/clt/stl/charlotte-to-st-louis) - [Flights from Hartford (BDL) to St. Louis (STL)](https://www.expedia.com/lp/flights/bdl/stl/hartford-to-st-louis) - [Flights from Dallas (DFW) to St. Louis (STL)](https://www.expedia.com/lp/flights/dfw/stl/dallas-to-st-louis) - [Flights from Columbia (CAE) to St. Louis (STL)](https://www.expedia.com/lp/flights/cae/stl/columbia-to-st-louis) - [Flights from Harrisburg (MDT) to St. Louis (STL)](https://www.expedia.com/lp/flights/mdt/stl/harrisburg-to-st-louis) - [Flights from Houston (HOU) to St. Louis (STL)](https://www.expedia.com/lp/flights/hou/stl/houston-to-st-louis) - [Flights from Denver (DEN) to St. Louis (STL)](https://www.expedia.com/lp/flights/den/stl/denver-to-st-louis) - [Flights from Pittsburgh (PIT) to St. Louis (STL)](https://www.expedia.com/lp/flights/pit/stl/pittsburgh-to-st-louis) - [Flights from Newark Liberty Intl. Airport (EWR) to St. Louis (STL)](https://www.expedia.com/lp/flights/ewr/stl/newark-liberty-intl-airport-to-st-louis) - [Flights from Philadelphia (PHL) to St. Louis (STL)](https://www.expedia.com/lp/flights/phl/stl/philadelphia-to-st-louis) - [Flights from Pensacola (PNS) to St. Louis (STL)](https://www.expedia.com/lp/flights/pns/stl/pensacola-to-st-louis) - [Flights from New York (LGA) to St. Louis (STL)](https://www.expedia.com/lp/flights/lga/stl/new-york-to-st-louis) - [Flights from Asheville (AVL) to St. Louis (STL)](https://www.expedia.com/lp/flights/avl/stl/asheville-to-st-louis) - [Flights from San Juan (SJU) to St. Louis (STL)](https://www.expedia.com/lp/flights/sju/stl/san-juan-to-st-louis) - [Flights from Cedar Rapids (CID) to St. Louis (STL)](https://www.expedia.com/lp/flights/cid/stl/cedar-rapids-to-st-louis) - [Flights from Springfield (SGF) to St. Louis (STL)](https://www.expedia.com/lp/flights/sgf/stl/springfield-to-st-louis) - [Flights from Los Angeles (LAX) to St. Louis (STL)](https://www.expedia.com/lp/flights/lax/stl/los-angeles-to-st-louis) - [Flights from Seattle (SEA) to St. Louis (STL)](https://www.expedia.com/lp/flights/sea/stl/seattle-to-st-louis) - [Flights from San Francisco (SFO) to St. Louis (STL)](https://www.expedia.com/lp/flights/sfo/stl/san-francisco-to-st-louis) - [Flights from Las Vegas (LAS) to St. Louis (STL)](https://www.expedia.com/lp/flights/las/stl/las-vegas-to-st-louis) - [Flights from Oakland (OAK) to St. Louis (STL)](https://www.expedia.com/lp/flights/oak/stl/oakland-to-st-louis) - [Flights from Toronto (YYZ) to St. Louis (STL)](https://www.expedia.com/lp/flights/yyz/stl/toronto-to-st-louis) - [Flights from Richmond (RIC) to St. Louis (STL)](https://www.expedia.com/lp/flights/ric/stl/richmond-to-st-louis) - [Flights from Columbus (CMH) to St. Louis (STL)](https://www.expedia.com/lp/flights/cmh/stl/columbus-to-st-louis) - [Flights from Nashville (BNA) to St. Louis (STL)](https://www.expedia.com/lp/flights/bna/stl/nashville-to-st-louis) - [Flights from Cleveland (CLE) to St. Louis (STL)](https://www.expedia.com/lp/flights/cle/stl/cleveland-to-st-louis) - [Flights from Salt Lake City (SLC) to St. Louis (STL)](https://www.expedia.com/lp/flights/slc/stl/salt-lake-city-to-st-louis) - [Flights from Houston (IAH) to St. Louis (STL)](https://www.expedia.com/lp/flights/iah/stl/houston-to-st-louis) - [Flights from Albuquerque (ABQ) to St. Louis (STL)](https://www.expedia.com/lp/flights/abq/stl/albuquerque-to-st-louis) - [Flights from Tucson (TUS) to St. Louis (STL)](https://www.expedia.com/lp/flights/tus/stl/tucson-to-st-louis) - [Flights from Boise (BOI) to St. Louis (STL)](https://www.expedia.com/lp/flights/boi/stl/boise-to-st-louis) - [Flights from Fresno (FAT) to St. Louis (STL)](https://www.expedia.com/lp/flights/fat/stl/fresno-to-st-louis) - [Flights from Colorado Springs (COS) to St. Louis (STL)](https://www.expedia.com/lp/flights/cos/stl/colorado-springs-to-st-louis) - [Flights from Honolulu (HNL) to St. Louis (STL)](https://www.expedia.com/lp/flights/hnl/stl/honolulu-to-st-louis) - [Flights from Ontario Intl. Airport (ONT) to St. Louis (STL)](https://www.expedia.com/lp/flights/ont/stl/ontario-to-st-louis) - [Flights from Des Moines (DSM) to St. Louis (STL)](https://www.expedia.com/lp/flights/dsm/stl/des-moines-to-st-louis) - [Flights from Portland (PDX) to St. Louis (STL)](https://www.expedia.com/lp/flights/pdx/stl/portland-to-st-louis) - [Flights from West Palm Beach (PBI) to St. Louis (STL)](https://www.expedia.com/lp/flights/pbi/stl/west-palm-beach-to-st-louis) - [Flights from Chattanooga (CHA) to St. Louis (STL)](https://www.expedia.com/lp/flights/cha/stl/chattanooga-to-st-louis) - [Flights from Cincinnati (CVG) to St. Louis (STL)](https://www.expedia.com/lp/flights/cvg/stl/cincinnati-to-st-louis) - [Flights from Tulsa (TUL) to St. Louis (STL)](https://www.expedia.com/lp/flights/tul/stl/tulsa-to-st-louis) - [Flights from Orange County (SNA) to St. Louis (STL)](https://www.expedia.com/lp/flights/sna/stl/orange-county-to-st-louis) - [Flights from Miami (MIA) to St. Louis (STL)](https://www.expedia.com/lp/flights/mia/stl/miami-to-st-louis) - [Flights from Dayton (DAY) to St. Louis (STL)](https://www.expedia.com/lp/flights/day/stl/dayton-to-st-louis) - [Flights from Spokane (GEG) to St. Louis (STL)](https://www.expedia.com/lp/flights/geg/stl/spokane-to-st-louis) - [Flights from Atlanta (ATL) to St. Louis (STL)](https://www.expedia.com/lp/flights/atl/stl/atlanta-to-st-louis) \*Available to One Key members. ## Other language versions ```yaml hreflang: x-default: https://www.expedia.com/lp/flights/isp/stl/islip-to-st-louis nb-NO: https://www.expedia.no/lp/fly/isp/stl/islip-til-st-louis es: https://www.expedia.com/es/lp/vuelos/isp/stl/islip-a-st-louis en-US: https://www.expedia.com/lp/flights/isp/stl/islip-to-st-louis id-ID: https://www.expedia.co.id/lp/flights/isp/stl/islip-to-st-louis ar: https://www.expedia.sa/lp/flights/isp/stl/islip-to-st-louis ```