HomeSearch by dateVacation packagesHotelsFlight dealsCar rentalTravel tips & news
Islip

$169+ 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 3/15. Fares are subject to change and may not be available on all flights or dates of travel.
TYS — ISP
Mar 16 — Mar 231
Mon 3/16
Mon 3/23
1 adult, Economy
We work with more than 300 partners to bring you better travel deals

Find cheap flights from Knoxville to Islip with Cheapflights

1. Tell us where you want to go

Enter your travel information like dates, passengers, trip type (one-way or round trip), and preferred cabin class then click “Find deals”

2. Select your favorite providers

We find the providers serving your travel needs. Choose up to four travel providers to compare side-by-side for flights, hotels, or car rentals.

3. Compare prices and book

Review each provider’s pricing and select the best option for you! Book through your favorite provider’s website for a seamless experience.

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 February 14, 2026.

This Southwest deal was found by Cheapflights users on 2/11. 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 4/78:15 am
TYS
-
ISP
1 stop5h 35m
Southwest
Wed 4/154:10 pm
ISP
-
TYS
1 stop4h 40m
Southwest
Deal found 2/11$279
This Southwest deal was found by Cheapflights users on 2/11. 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 3/167:50 am
TYS
-
ISP
1 stop9h 30m
Southwest
Wed 3/184:40 pm
ISP
-
TYS
1 stop4h 30m
Southwest
Deal found 2/11$294
This Southwest deal was found by Cheapflights users on 2/12. 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.
Wed 4/88:15 am
TYS
-
ISP
1 stop3h 40m
Southwest
Sun 4/125:25 pm
ISP
-
TYS
1 stop4h 35m
Southwest
Deal found 2/12$308
This Southwest deal was found by Cheapflights users on 2/13. 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 4/208:05 am
TYS
-
ISP
1 stop3h 45m
Southwest
Thu 4/238:35 am
ISP
-
TYS
2 stops9h 35m
Southwest
Deal found 2/13$323
This Southwest deal was found by Cheapflights users on 2/12. 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.
Wed 3/117:50 am
TYS
-
ISP
1 stop3h 50m
Southwest
Thu 3/125:55 pm
ISP
-
TYS
1 stop4h 15m
Southwest
Deal found 2/12$328

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 February 14, 2026.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$279
(Southwest)

One-way from

$169
(Southwest)

Popular in

November

Cheapest in

April

Average price

$368
Provider with most accurate pricing for Knoxville McGhee Tyson-Islip Long Island flight deals.
Search Deals
Provider most trusted by Cheapflights users for Knoxville McGhee Tyson-Islip Long Island flights.
Search Deals
From Knoxville McGhee Tyson to Islip Long Island
Search Deals
One-way flight from Knoxville McGhee Tyson to Islip Long Island
Search Deals
Highest demand for flights based on searches. 13% potential increase in price ($46 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 3% potential price decrease ($10 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in February 2026
Search Deals

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 February 14, 2026.
Use the filters below to find and compare flights from Knoxville to Islip that are best for you.

Fly from

Knoxville

Fly to

Islip

Route

Depart

Return

Price

KnoxvilleIslip

TYS - ISP

TYSISP

Knoxville McGhee Tyson

Tue 4/7

8:15 am-1:50 pm

1 stop5h 35m

Islip Long Island

Wed 4/15

4:10 pm-8:50 pm

1 stop4h 40m

$279

KnoxvilleIslip

TYS - ISP

TYSISP

Knoxville McGhee Tyson

Mon 3/16

7:50 am-5:20 pm

1 stop9h 30m

Islip Long Island

Wed 3/18

4:40 pm-9:10 pm

1 stop4h 30m

$294

KnoxvilleIslip

TYS - ISP

TYSISP

Knoxville McGhee Tyson

Tue 5/12

8:15 am-1:50 pm

1 stop5h 35m

Islip Long Island

Fri 5/15

4:30 pm-9:15 pm

1 stop4h 45m

$308

KnoxvilleIslip

TYS - ISP

TYSISP

Knoxville McGhee Tyson

Wed 4/8

8:15 am-11:55 am

1 stop3h 40m

Islip Long Island

Sun 4/12

5:25 pm-10:00 pm

1 stop4h 35m

$308

KnoxvilleIslip

TYS - ISP

TYSISP

Knoxville McGhee Tyson

Mon 4/20

8:05 am-11:50 am

1 stop3h 45m

Islip Long Island

Thu 4/23

8:35 am-6:10 pm

2 stops9h 35m

$323

KnoxvilleIslip

TYS - ISP

TYSISP

Knoxville McGhee Tyson

Sun 3/15

7:40 am-11:45 am

1 stop4h 05m

$169

KnoxvilleIslip

TYS - ISP

TYSISP

Knoxville McGhee Tyson

Fri 6/26

7:30 am-11:50 am

1 stop4h 20m

$189

KnoxvilleIslip

TYS - ISP

TYSISP

Knoxville McGhee Tyson

Sat 6/27

7:10 am-5:29 pm

2 stops10h 19m

$372

KnoxvilleIslip

TYS - ISP

TYSISP

Knoxville McGhee Tyson

Thu 6/25

7:15 am-9:08 am

2 stops25h 53m

$417

Flights are sorted by cheapest round-trip flights first.

Deals found on 2/14

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 February.
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.

Cheapflights Insights

Everything you need to know about your flight from Knoxville to Islip

What is the cheapest month to book a flight from Knoxville to Islip, New York?

Currently, July is the cheapest month in which you can book a flight from Knoxville to Islip, New York (average of $41). Flying from Knoxville to Islip, New York in December is currently the most expensive (average of $168). 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.

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 5h 35m. The distance between Knoxville and Islip, New York is about 682 mi.

  • 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.

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

    Currently, July is the cheapest month in which you can book a flight from Knoxville to Islip, New York (average of $41). Flying from Knoxville to Islip, New York in December is currently the most expensive (average of $168). 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

Traveling to a place near Islip?

Book flights to Islip if you plan to visit one of these locations
Riverhead

Browse thousands of different options on Cheapflights for your next trip

Toggle through the tabs below to find thousands of options on Cheapflights for your next trip.

Alternative routes for Knoxville to Islip

See prices for flight routes from nearby airports that may be better suited for you.
Nashville to Newark flights
Nashville to LaGuardia flights
Nashville to John F Kennedy Intl flights
Memphis to LaGuardia flights
Memphis to John F Kennedy Intl flights
Memphis to Newark flights
Chattanooga to LaGuardia flights
Knoxville to LaGuardia flights
Chattanooga to Newark flights
Knoxville to John F Kennedy Intl flights
Chattanooga to John F Kennedy Intl flights
Knoxville to Newark flights
Nashville to Buffalo flights
Nashville to Albany flights
Chattanooga to Rochester flights
Knoxville to White Plains flights
Nashville to White Plains flights
Nashville to Stewart flights
Memphis to Buffalo flights
Blountville to Newark flights
Blountville to John F Kennedy Intl flights
Nashville to Syracuse flights
Blountville to LaGuardia flights
Nashville to Rochester flights
Knoxville to Albany flights
Knoxville to Stewart flights
Memphis to Albany flights
Chattanooga to Syracuse flights
Memphis to Rochester flights
Chattanooga to Stewart flights
Knoxville to Buffalo flights
Knoxville to Syracuse flights
Memphis to White Plains flights
Knoxville to Rochester flights
Blountville to Buffalo flights
Chattanooga to White Plains flights
Memphis to Stewart flights
Chattanooga to Albany flights
Nashville to Ithaca flights
Chattanooga to Buffalo flights
Knoxville to Elmira flights
Memphis to Syracuse flights
Knoxville to Ithaca flights
Blountville to Stewart flights
Blountville to Syracuse flights
Nashville to Watertown flights
Nashville to Islip flights
Chattanooga to Elmira flights
Memphis to Binghamton flights

100% Free

Cheapflights is completely free to use, so you can start saving the moment you arrive.

Book with Flexibility

Our users can plan ahead with confidence and find flights with no change fees

Travel Smart

Millions of people come to us for their flight needs every year. We help make travel planning easy by providing useful insights and data-driven graphs that can inform your decisions.