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$216+ Cheap flights from Islip, NY to Knoxville (ISP - TYS)

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 1/4. Fares are subject to change and may not be available on all flights or dates of travel.
ISP — TYS
Aug 20 — Aug 271
Thu 8/20
Thu 8/27
1 adult, Economy
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Cheap flight deals from Islip to Knoxville

Cheapest flights from Islip to Knoxville
Explore the most affordable flight options available from Islip to Knoxville. Find the lowest fares from popular airlines and budget airlines, with prices last updated on July 21, 2026.

This Southwest deal was found by Cheapflights users on 7/20. 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 8/2512:55 pm
ISP
-
TYS
1 stop6h 55m
Southwest
Tue 9/18:05 am
TYS
-
ISP
1 stop4h 05m
Southwest
Deal found 7/20$293
This Kiwi.com deal was found by Cheapflights users on 7/20. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 8/2110:57 am
ISP
-
TYS
1 stop8h 08m
Multiple Airlines
Mon 8/312:49 pm
TYS
-
ISP
2 stops25h 58m
Multiple Airlines
Deal found 7/20$316
This Kiwi.com deal was found by Cheapflights users on 7/20. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 8/2410:57 am
ISP
-
TYS
1 stop8h 08m
Multiple Airlines
Mon 8/312:49 pm
TYS
-
ISP
2 stops25h 58m
Multiple Airlines
Deal found 7/20$320
This Kiwi.com deal was found by Cheapflights users on 7/20. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 8/2110:57 am
ISP
-
TYS
1 stop8h 08m
Multiple Airlines
Fri 8/282:51 pm
TYS
-
ISP
1 stop19h 02m
Multiple Airlines
Deal found 7/20$349
This Kiwi.com deal was found by Cheapflights users on 7/20. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 8/2410:57 am
ISP
-
TYS
1 stop8h 08m
Multiple Airlines
Fri 8/282:51 pm
TYS
-
ISP
1 stop19h 02m
Multiple Airlines
Deal found 7/20$353
This Southwest deal was found by Cheapflights users on 7/20. 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.
Mon 8/244:05 pm
ISP
-
TYS
1 stop3h 50m
Southwest
Fri 8/2812:40 pm
TYS
-
ISP
2 stops9h 25m
Southwest
Deal found 7/20$362
This Kiwi.com deal was found by Cheapflights users on 7/20. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 8/2110:57 am
ISP
-
TYS
1 stop8h 08m
Multiple Airlines
Thu 8/2712:55 pm
TYS
-
ISP
2 stops6h 14m
Multiple Airlines
Deal found 7/20$366

Find flight deals from Islip to Knoxville

Discover tips and strategies to find the most affordable flight options for your journey from Islip (ISP) to Knoxville (TYS). 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 July 21, 2026.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$293
(Southwest)

One-way from

$216
(Southwest)

Popular in

May

Cheapest in

August

Average price

$401
Provider with most accurate pricing for Islip Long Island-Knoxville McGhee Tyson flight deals.
Search Deals
Provider most trusted by Cheapflights users for Islip Long Island-Knoxville McGhee Tyson flights.
Search Deals
From Islip Long Island to Knoxville McGhee Tyson
Search Deals
One-way flight from Islip Long Island to Knoxville McGhee Tyson
Search Deals
Highest demand for flights based on searches. 2% potential increase in price ($9 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 1% potential price decrease ($6 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in July 2026
Search Deals

Cheapflights Fare Finder

 
Customize your flight search to find flights from Islip to Knoxville 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 July 21, 2026.
Use the filters below to find and compare flights from Islip to Knoxville that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

Cheapest round-trip
Quickest round-trip

IslipKnoxville

ISP - TYS

ISPTYS

Islip Long Island

Tue 8/25

12:55 pm-7:50 pm

1 stop6h 55m

Knoxville McGhee Tyson

Tue 9/1

8:05 am-12:10 pm

1 stop4h 05m

$293

IslipKnoxville

ISP - TYS

ISPTYS

Islip Long Island

Tue 8/18

12:55 pm-7:50 pm

1 stop6h 55m

Knoxville McGhee Tyson

Mon 8/24

12:40 pm-10:05 pm

2 stops9h 25m

$402

IslipKnoxville

ISP - TYS

ISPTYS

Islip Long Island

Sat 8/8

7:46 pm-8:36 am

2 stops36h 50m

Knoxville McGhee Tyson

Fri 8/14

6:29 pm-9:53 am

1 stop15h 24m

$416

IslipKnoxville

ISP - TYS

ISPTYS

Islip Long Island

Mon 9/14

6:10 am-12:20 pm

2 stops6h 10m

Knoxville McGhee Tyson

Fri 9/18

1:00 pm-10:05 pm

2 stops9h 05m

$419

IslipKnoxville

ISP - TYS

ISPTYS

Islip Long Island

Sat 8/8

3:15 pm-7:20 pm

1 stop4h 05m

Knoxville McGhee Tyson

Fri 8/14

1:00 pm-9:30 pm

1 stop8h 30m

$432

IslipKnoxville

ISP - TYS

ISPTYS

Islip Long Island

Tue 8/4

3:20 pm-7:50 pm

1 stop4h 30m

Knoxville McGhee Tyson

Wed 8/5

7:00 am-2:55 pm

2 stops7h 55m

$462

IslipKnoxville

ISP - TYS

ISPTYS

Islip Long Island

Mon 8/3

10:57 am-11:33 pm

1 stop12h 36m

Knoxville McGhee Tyson

Fri 8/7

7:30 am-7:01 pm

2 stops11h 31m

$479
Cheapest one-way

IslipKnoxville

ISP - TYS

ISPTYS

Islip Long Island

Mon 1/4

5:35 am-3:00 pm

2 stops9h 25m

$216

IslipKnoxville

ISP - TYS

ISPTYS

Islip Long Island

Mon 8/3

2:28 pm-3:30 pm

2 stops25h 02m

$254
Quickest one-way

IslipKnoxville

ISP - TYS

ISPTYS

Islip Long Island

Thu 12/31

12:25 pm-7:50 pm

1 stop7h 25m

$264

Flights are sorted by cheapest round-trip flights first.

Deals found on 7/18

Showing 1-10 of 14 resultsSorted by cheapest first
1
2

Compare providers for flights from Islip to Knoxville

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 Islip to Knoxville in July.
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 Islip, New York-Knoxville flights, users find the pricing of FlightHub to be most consistent on Cheapflights vs. FlightHub Users can find the same prices on Islip, New York-Knoxville flight deals on Cheapflights vs. FlightHub >95% of the time. Price accuracy is based on data collected from Islip, New York-Knoxville flight searches over the past month and is updated monthly.
  • Most trusted provider: When it comes to deals on Islip, New York-Knoxville 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 Islip, New York-Knoxville 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 Islip to Knoxville

Have a flexible travel schedule? Discover the best time to fly to Knoxville from Islip 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 Knoxville

Get insights into the airlines that provide service to Knoxville. 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 Knoxville. Reviews last updated July 21, 2026.
Peruse reviews from past customers who have flown with Southwest from Islip to Knoxville to help guide your decision. You can also see how each airline stacks up in terms of entertainment options, comfort, food, crew/service, and boarding process.
Southwest
8.0
Very good
4,239 reviews

Overall

8.0

Crew

8.6

Comfort

8.0

Boarding

8.1

Entertainment

7.5

Food

7.0

Reviews

1 / 20
8.0
Excellent

John,May 2025

PVD - BNA

It’s southwest so no frills but clean, efficient and got me to my location.
Southwest
8.0
Very good
4,239 reviews
Southwest
8.0
Very good
4,239 reviews

Overall

8.0

Crew

8.6

Comfort

8.0

Boarding

8.1

Entertainment

7.5

Food

7.0

Reviews

1 / 20
8.0
Excellent

John,May 2025

PVD - BNA

It’s southwest so no frills but clean, efficient and got me to my location.

Related info for your journey

Find useful and relevant information for your journey from Islip to Knoxville. 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 Islip, New York to Knoxville?

    A quick flight from Islip, New York to Knoxville can take about 6h 55m. Southwest provides one of the quickest options available for as low as $293. The distance between Islip, New York and Knoxville is about 682 mi.

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

    Our cheapest airline available from Islip, New York to Knoxville is Southwest. Our recent data shows that you can find tickets from as low as $256 on this airline.

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

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

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

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

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

    Yes. Cheapflights offers flight deals from Islip to Knoxville 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 Knoxville?

Book flights to Knoxville if you plan to visit one of these locations
Cherokee
Crossville
Morristown
Bryson City
Murphy
Alcoa

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Top airline flying from Islip to Knoxville

Discover the top airline that operate flights from Islip to Knoxville. 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 July 21, 2026.
AirlineCheapestAverageFlexibilityOn-time
SouthwestCheapest$256Average$400FlexibilityNo cancel feeOn-time63%

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