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Islip

$184+ Cheap flights from Knoxville to Islip, NY (TYS - ISP)

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 8/6. Fares are subject to change and may not be available on all flights or dates of travel.
TYS — ISP
May 23 — May 301
Sat 5/23
Sat 5/30
1 adult, Economy
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Cheap flight deals from Knoxville to Islip

Cheapest flights from Knoxville to Islip
Explore the most affordable flight options available from Knoxville to Islip. Find the lowest fares from popular airlines and budget airlines, with prices last updated on April 23, 2026.

This Southwest deal was found by Cheapflights users on 4/23. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 8/178:25 am
TYS
-
ISP
1 stop4h 10m
Southwest
Mon 8/246:10 am
ISP
-
TYS
2 stops11h 00m
Southwest
Deal found 4/23$286
This Southwest deal was found by Cheapflights users on 4/20. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 6/96:55 pm
TYS
-
ISP
2 stops13h 10m
Southwest
Wed 6/242:55 pm
ISP
-
TYS
1 stop6h 20m
Southwest
Deal found 4/20$307
This Southwest deal was found by Cheapflights users on 4/21. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 5/198:15 am
TYS
-
ISP
1 stop3h 40m
Southwest
Tue 5/264:10 pm
ISP
-
TYS
1 stop4h 40m
Southwest
Deal found 4/21$316
This Kiwi.com deal was found by Cheapflights users on 4/22. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 5/227:24 pm
TYS
-
ISP
1 stop14h 41m
Multiple Airlines
Fri 5/2911:00 am
ISP
-
TYS
1 stop12h 37m
Multiple Airlines
Deal found 4/22$325
This Trip.com deal was found by Cheapflights users on 4/19. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 5/257:24 pm
TYS
-
ISP
1 stop21h 53m
Multiple Airlines
Fri 5/2911:00 am
ISP
-
TYS
1 stop12h 37m
Multiple Airlines
Deal found 4/19$371
This Southwest deal was found by Cheapflights users on 4/19. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 5/128:15 am
TYS
-
ISP
1 stop3h 40m
Southwest
Tue 5/194:10 pm
ISP
-
TYS
1 stop4h 40m
Southwest
Deal found 4/19$377

Find flight deals from Knoxville to Islip

Discover tips and strategies to find the most affordable flight options for your journey from Knoxville (TYS) to Islip (ISP). Learn about various techniques such as flexible date searches, comparing prices across and setting up price alerts. Use these methods to find the cheapest flights available for your travel needs. Data last updated April 23, 2026.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$286
(Southwest)

One-way from

$184
(Southwest)

Popular in

March

Cheapest in

June

Average price

$365
Provider with most accurate pricing for Knoxville McGhee Tyson-Islip Long Island flight deals.
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Provider most trusted by Cheapflights users for Knoxville McGhee Tyson-Islip Long Island flights.
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From Knoxville McGhee Tyson to Islip Long Island
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One-way flight from Knoxville McGhee Tyson to Islip Long Island
Search Deals
Highest demand for flights based on searches. 16% potential increase in price ($66 potential increase over avg. RT price).
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Cheapest flight prices on average. 3% potential price decrease ($13 potential savings vs. average RT price).
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Average for round-trip flights in April 2026
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Cheapflights Fare Finder

 
Customize your flight search to find flights from Knoxville 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 2,558,603 searches. Data last updated April 23, 2026.
Use the filters below to find and compare flights from Knoxville to Islip that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

Cheapest round-trip

KnoxvilleIslip

TYS - ISP

TYSISP

Knoxville McGhee Tyson

Tue 6/9

6:55 pm-8:05 am

2 stops13h 10m

Islip Long Island

Wed 6/24

2:55 pm-9:15 pm

1 stop6h 20m

$307
Quickest round-trip

KnoxvilleIslip

TYS - ISP

TYSISP

Knoxville McGhee Tyson

Mon 8/17

8:25 am-12:35 pm

1 stop4h 10m

Islip Long Island

Mon 8/24

4:05 pm-7:55 pm

1 stop3h 50m

$319

KnoxvilleIslip

TYS - ISP

TYSISP

Knoxville McGhee Tyson

Tue 5/19

8:15 am-11:55 am

1 stop3h 40m

Islip Long Island

Tue 5/26

6:30 am-5:10 pm

2 stops10h 40m

$321

KnoxvilleIslip

TYS - ISP

TYSISP

Knoxville McGhee Tyson

Fri 5/22

7:24 pm-10:05 am

1 stop14h 41m

Islip Long Island

Fri 5/29

11:00 am-11:37 pm

1 stop12h 37m

$325

KnoxvilleIslip

TYS - ISP

TYSISP

Knoxville McGhee Tyson

Tue 5/12

8:15 am-11:55 am

1 stop3h 40m

Islip Long Island

Tue 5/19

4:10 pm-8:50 pm

1 stop4h 40m

$377

KnoxvilleIslip

TYS - ISP

TYSISP

Knoxville McGhee Tyson

Fri 5/22

2:45 pm-11:30 pm

2 stops8h 45m

Islip Long Island

Thu 5/28

12:30 pm-8:20 pm

2 stops7h 50m

$397
Cheapest one-way
Quickest one-way

KnoxvilleIslip

TYS - ISP

TYSISP

Knoxville McGhee Tyson

Thu 8/6

12:30 pm-9:30 pm

1 stop9h 00m

$184

KnoxvilleIslip

TYS - ISP

TYSISP

Knoxville McGhee Tyson

Tue 5/26

7:05 am-6:30 pm

2 stops11h 25m

$190

KnoxvilleIslip

TYS - ISP

TYSISP

Knoxville McGhee Tyson

Tue 5/5

12:50 pm-10:10 pm

2 stops9h 20m

$224

KnoxvilleIslip

TYS - ISP

TYSISP

Knoxville McGhee Tyson

Mon 5/25

6:35 am-4:30 pm

2 stops9h 55m

$224

Flights are sorted by cheapest round-trip flights first.

Deals found on 4/20

Showing 1-10 of 11 resultsSorted by cheapest first
1
2

Compare providers for flights from Knoxville to Islip

Provider information is updated monthly. Please note that these providers often have deals for this flight, but the availability may vary on a day-by-day basis on Cheapflights.
Use the table below to compare price accuracy, trust ratings, and cancellation policies for each provider offering flight deals from Knoxville to Islip in April.
ProviderPrice AccuracyTrust Score*
ExpediaPrice Accuracy1 starTrust Score*3 stars
FlightHubPrice Accuracy3 starsTrust Score*3 stars

*The Trust Score is based on feedback from users after their booking experience. It measures overall satisfaction, helping us identify issues like hidden fees, problems during the ticketing process, and the quality of customer service. This score is our best indicator of the provider's quality and reliability.

  • Most accurate provider: When it comes to deals on Knoxville-Islip, New York flights, users find the pricing of FlightHub to be most consistent on Cheapflights vs. FlightHub Users can find the same prices on Knoxville-Islip, New York flight deals on Cheapflights vs. FlightHub >95% of the time. Price accuracy is based on data collected from Knoxville-Islip, New York flight searches over the past month and is updated monthly.
  • Most trusted provider: When it comes to deals on Knoxville-Islip, New York flights, Cheapflights users trust FlightHub the most. FlightHub has received a user feedback score of 3 out of 3 stars (3 being the best), meaning they have been trusted the most by Cheapflights users looking for Knoxville-Islip, New York flight deals. Provider user feedback score is based on Cheapflights searches over the past month and is updated monthly.

Best time to book a flight from Knoxville to Islip

Have a flexible travel schedule? Discover the best time to fly to Islip from Knoxville 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 April 23, 2026.
Get a feel of what it's like to fly with Southwest from Knoxville to Islip by reading reviews from past customers. Users have also rated airlines in terms of entertainment options, comfort, food, crew/service, and boarding process.
Southwest
8.0
Very good
4,334 reviews

Food

7.0

Crew

8.6

Boarding

8.1

Overall

8.0

Entertainment

7.5

Comfort

8.0

Reviews

1 / 20
2.0
Mediocre

Dominic,Mar 2026

MCO - SMF

I had to try and sleep on the floor of the Austin airport. I spent 12 hours there. The airline policies were so poor, that a near violent argument broke out between the people in front of me and the flight attendants - making for a super stressful situation at 30,000 feet. Garbage airline choice by Kayak Garbage idea to book a flight with a layover. Next time I will pay for a quality booking myself, and somehow force the company to reimburse it.
Southwest
8.0
Very good
4,334 reviews
Southwest
8.0
Very good
4,334 reviews

Food

7.0

Crew

8.6

Boarding

8.1

Overall

8.0

Entertainment

7.5

Comfort

8.0

Reviews

1 / 20
2.0
Mediocre

Dominic,Mar 2026

MCO - SMF

I had to try and sleep on the floor of the Austin airport. I spent 12 hours there. The airline policies were so poor, that a near violent argument broke out between the people in front of me and the flight attendants - making for a super stressful situation at 30,000 feet. Garbage airline choice by Kayak Garbage idea to book a flight with a layover. Next time I will pay for a quality booking myself, and somehow force the company to reimburse it.

Related info for your journey

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

  • How long is the flight from Knoxville to Islip, New York?

    Departing from Knoxville to Islip, New York will take you 13h 10m. The distance between Knoxville and Islip, New York is about 682 mi.

  • What is the cheapest airline to fly from Knoxville to Islip, New York round-trip?

    Flying on Southwest is currently your cheapest option to Islip, New York, with prices starting at $307.

  • Can I find deals for flights from Knoxville to Islip that include hotel bookings?

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

  • How can I find direct flights from Knoxville to Islip?

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

  • Can I find deals for business class flights from Knoxville to Islip?

    Yes. Cheapflights offers flight deals from Knoxville 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.

See more FAQs

Traveling to a place near Islip?

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Top airline flying from Knoxville to Islip

Discover the top airline that operate flights from Knoxville to Islip. Compare their services, reliability, and customer satisfaction ratings to choose the airline that best suits your travel preferences and needs. Over the last 7 days, Cheapflights users made 2,558,603 searches. Data last updated April 23, 2026.
AirlineCheapestAverageFlexibilityOn-time
SouthwestCheapest$307Average$366FlexibilityNo cancel feeOn-time63%

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