$157+ 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 11/11. Fares are subject to change and may not be available on all flights or dates of travel.
ISP — TYS
Sep 3 — Sep 101
Round-trip
1 adult, Economy
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Find cheap flights from Islip to Knoxville 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
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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 Islip to Knoxville
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Cheapest flights from Islip to KnoxvilleExplore 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 August 4, 2026.
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 August 4, 2026.
This Southwest deal was found by Cheapflights users on 8/2. 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.
Sat 8/293:15 pm -
1 stop4h 05m
Thu 9/171:00 pm -
1 stop8h 35m
Deal found 8/2![Southwest logo]()
$303
This Kiwi.com deal was found by Cheapflights users on 8/3. 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 9/710:57 am -
1 stop7h 54m
Mon 9/144:18 pm -
1 stop24h 40m
Deal found 8/3![Multiple Airlines logo]()
$325
This Kiwi.com deal was found by Cheapflights users on 8/3. 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.
Thu 9/37:09 pm -
1 stop27h 47m
Thu 9/1010:54 am -
2 stops23h 34m
Deal found 8/3![Multiple Airlines logo]()
$331
This Southwest deal was found by Cheapflights users on 8/3. 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.
Thu 9/36:45 am -
1 stop10h 25m
Thu 9/101:00 pm -
1 stop8h 35m
Deal found 8/3![Southwest logo]()
$350
This Southwest deal was found by Cheapflights users on 8/2. 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 8/263:20 pm -
1 stop4h 30m
Mon 8/318:25 am -
1 stop4h 10m
Deal found 8/2![Southwest logo]()
$355
Best flights from Islip to KnoxvilleDiscover carefully curated flight deals from Islip to Knoxville that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated August 4, 2026.
Discover carefully curated flight deals from Islip to Knoxville that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated August 4, 2026.
This Southwest deal was found by Cheapflights users on 8/2. 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.
Sat 8/293:15 pm -
1 stop4h 05m
Thu 9/171:00 pm -
1 stop8h 35m
Deal found 8/2![Southwest logo]()
$303
This Kiwi.com deal was found by Cheapflights users on 8/3. 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 9/710:57 am -
1 stop7h 54m
Mon 9/144:18 pm -
1 stop24h 40m
Deal found 8/3![Multiple Airlines logo]()
$325
This Southwest deal was found by Cheapflights users on 8/3. 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.
Thu 9/36:45 am -
1 stop10h 25m
Thu 9/101:00 pm -
1 stop8h 35m
Deal found 8/3![Southwest logo]()
$350
This Southwest deal was found by Cheapflights users on 7/31. 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.
Sat 8/155:30 am -
2 stops9h 10m
Sat 8/297:50 am -
1 stop6h 40m
Deal found 7/31![Southwest logo]()
$432
This Southwest deal was found by Cheapflights users on 8/2. 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 8/1910:30 am -
2 stops9h 20m
Mon 8/2412:40 pm -
2 stops9h 25m
Deal found 8/2![Southwest logo]()
$449
This Southwest deal was found by Cheapflights users on 8/2. 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 8/266:05 am -
2 stops12h 50m
Mon 8/311:00 pm -
2 stops9h 05m
Deal found 8/2![Southwest logo]()
$453
This Southwest deal was found by Cheapflights users on 8/1. 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 9/76:10 am -
2 stops11h 00m
Mon 9/141:00 pm -
2 stops9h 10m
Deal found 8/1![Southwest logo]()
$468
This Southwest deal was found by Cheapflights users on 7/31. 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.
Fri 8/144:05 pm -
1 stop3h 50m
Mon 8/171:00 pm -
1 stop8h 30m
Deal found 7/31![Southwest logo]()
$497
Last-minute flights from Islip to KnoxvilleDiscover last-minute flight deals from Islip to Knoxville. Data last updated August 4, 2026 and is based on user searches.
Discover last-minute flight deals from Islip to Knoxville. Data last updated August 4, 2026 and is based on user searches.
This Southwest deal was found by Cheapflights users on 8/2. 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 8/263:20 pm -
1 stop4h 30m
Mon 8/318:25 am -
1 stop4h 10m
Deal found 8/2![Southwest logo]()
$355
This Southwest deal was found by Cheapflights users on 8/2. 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.
Sat 8/293:15 pm -
1 stop4h 05m
Thu 9/171:00 pm -
1 stop8h 35m
Deal found 8/2![Southwest logo]()
$303
This Kiwi.com deal was found by Cheapflights users on 8/3. 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.
Thu 9/37:09 pm -
1 stop27h 47m
Thu 9/1010:54 am -
2 stops23h 34m
Deal found 8/3![Multiple Airlines logo]()
$331
This Southwest deal was found by Cheapflights users on 8/3. 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.
Thu 9/36:45 am -
1 stop10h 25m
Thu 9/101:00 pm -
1 stop8h 35m
Deal found 8/3![Southwest logo]()
$350
This Kiwi.com deal was found by Cheapflights users on 8/3. 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 9/710:57 am -
1 stop7h 54m
Mon 9/144:18 pm -
1 stop24h 40m
Deal found 8/3![Multiple Airlines logo]()
$325
One-way flights from Islip to KnoxvilleSearch for one-way flight options from Islip to Knoxville. Find affordable one-way fares based on user searches. Data last updated August 4, 2026.
Search for one-way flight options from Islip to Knoxville. Find affordable one-way fares based on user searches. Data last updated August 4, 2026.
This Southwest deal was found by Cheapflights users on 8/2. 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 11/1112:30 pm -
2 stops7h 15m
Deal found 8/2![Southwest logo]()
$157
This Kiwi.com deal was found by Cheapflights users on 8/2. 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.
Wed 11/113:43 pm -
3 stops30h 22m
Deal found 8/2![Multiple Airlines logo]()
$161
This Kiwi.com deal was found by Cheapflights users on 8/2. 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.
Sun 10/184:13 pm -
2 stops29h 08m
Deal found 8/2![Multiple Airlines logo]()
$186
This Kiwi.com deal was found by Cheapflights users on 7/31. 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 10/93:02 pm -
2 stops18h 41m
Deal found 7/31![Multiple Airlines logo]()
$231
This Southwest deal was found by Cheapflights users on 8/2. 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.
Sun 10/1811:00 am -
1 stop10h 20m
Deal found 8/2![Southwest logo]()
$239
This Kiwi.com deal was found by Cheapflights users on 7/31. 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.
Thu 8/136:46 pm -
2 stops28h 45m
Deal found 7/31![Multiple Airlines logo]()
$269
This Southwest deal was found by Cheapflights users on 7/31. 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.
Thu 8/134:05 pm -
1 stop3h 50m
Deal found 7/31![Southwest logo]()
$339
This Southwest deal was found by Cheapflights users on 8/2. 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 8/1012:35 pm -
2 stops6h 00m
Deal found 8/2![Southwest logo]()
$344
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 August 4, 2026.
Most accurate provider | FlightHub 3 stars |
|---|---|
Most trusted provider | FlightHub 3 stars |
Round-trip from | $303 (Southwest) |
One-way from | $157 (Southwest) |
Popular in | May |
Cheapest in | August |
Average price | $340 |
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 August 4, 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
Cheapest round-trip
IslipKnoxville
ISP - TYS
ISPTYS
Islip Long Island
Sat 8/29
3:15 pm-7:20 pm
1 stop4h 05m
Knoxville McGhee Tyson
Thu 9/17
1:00 pm-9:35 pm
1 stop8h 35m
$303
IslipKnoxville
ISP - TYS
ISPTYS
Islip Long Island
Mon 9/7
10:57 am-6:51 pm
1 stop7h 54m
Knoxville McGhee Tyson
Mon 9/14
4:18 pm-4:58 pm
1 stop24h 40m
$325
IslipKnoxville
ISP - TYS
ISPTYS
Islip Long Island
Thu 9/3
6:45 am-5:10 pm
1 stop10h 25m
Knoxville McGhee Tyson
Thu 9/10
1:00 pm-9:35 pm
1 stop8h 35m
$350
IslipKnoxville
ISP - TYS
ISPTYS
Islip Long Island
Sat 8/15
5:30 am-2:40 pm
2 stops9h 10m
Knoxville McGhee Tyson
Sat 8/29
7:50 am-2:30 pm
1 stop6h 40m
$432
IslipKnoxville
ISP - TYS
ISPTYS
Islip Long Island
Wed 8/19
10:30 am-7:50 pm
2 stops9h 20m
Knoxville McGhee Tyson
Mon 8/24
12:40 pm-10:05 pm
2 stops9h 25m
$449
IslipKnoxville
ISP - TYS
ISPTYS
Islip Long Island
Wed 8/26
6:05 am-6:55 pm
2 stops12h 50m
Knoxville McGhee Tyson
Mon 8/31
1:00 pm-10:05 pm
2 stops9h 05m
$453
IslipKnoxville
ISP - TYS
ISPTYS
Islip Long Island
Mon 9/7
6:10 am-5:10 pm
2 stops11h 00m
Knoxville McGhee Tyson
Mon 9/14
1:00 pm-10:10 pm
2 stops9h 10m
$468
Quickest round-trip
IslipKnoxville
ISP - TYS
ISPTYS
Islip Long Island
Fri 8/14
4:05 pm-7:55 pm
1 stop3h 50m
Knoxville McGhee Tyson
Mon 8/17
1:00 pm-9:30 pm
1 stop8h 30m
$497
Cheapest one-way
IslipKnoxville
ISP - TYS
ISPTYS
Islip Long Island
Wed 11/11
4:05 pm-8:45 pm
1 stop4h 40m
$168
IslipKnoxville
ISP - TYS
ISPTYS
Islip Long Island
Fri 10/9
3:02 pm-9:43 am
2 stops18h 41m
$231
Showing 1-10 of 15 resultsSorted by cheapest first
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 August.
| Provider | Price Accuracy | Trust Score* |
|---|---|---|
| Price Accuracy1 star | Trust Score*3 stars | |
| Price Accuracy3 stars | Trust Score*3 stars |
- 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.
ISP-TYS
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 August 4, 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.
Food
7.0
Boarding
8.1
Comfort
8.0
Crew
8.6
Overall
8.0
Entertainment
7.5
Reviews
1 / 20
8.0
ExcellentJohn,May 2025
PVD - BNA
Food
7.0
Boarding
8.1
Comfort
8.0
Crew
8.6
Overall
8.0
Entertainment
7.5
Reviews
1 / 20
8.0
ExcellentJohn,May 2025
PVD - BNA
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.
Traveling to a place near Knoxville?
Book flights to Knoxville if you plan to visit one of these locationsCherokee
Crossville
Morristown
Bryson City
Murphy
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Other flights to Knoxville
Explore flights to Knoxville departing from other origins. Flights are based on user searches made on Cheapflights and were last updated on August 4, 2026.
Islip and Knoxville flights
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Browse through other flights departing from Islip. Flights are based on user searches made on Cheapflights and were last updated on August 4, 2026.
Popular flight searches
Check out other popular destinations found by fellow travelers in 2026
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 August 4, 2026.
| Airline | Cheapest | Average | Flexibility | On-time |
|---|---|---|---|---|
| Cheapest$256 | Average$400 | FlexibilityNo cancel fee | On-time63% |