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$86+ Cheap flights from Islip (ISP) to Colorado

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 11/15. Fares are subject to change and may not be available on all flights or dates of travel.
ISP — DEN
Nov 13 — Nov 201
Thu 11/13
Thu 11/20
1 adult, Economy
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Find flight deals from Islip to Colorado

Cheapest flights from Islip to Colorado
Explore the most affordable flight options available from Islip to Colorado. Find the lowest fares from popular airlines and budget airlines, with prices last updated on October 14, 2025.

This CheapOair deal was found by Cheapflights users on 10/12. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 10/306:37 pmISP - DEN
1 stop15h 38mFrontier
Sun 11/211:59 pmDEN - ISP
1 stop7h 10mFrontier
Deal found 10/12$155
This CheapOair deal was found by Cheapflights users on 10/13. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 11/168:49 amISP - DEN
1 stop25h 54mFrontier
Tue 11/1812:16 amDEN - ISP
1 stop8h 21mFrontier
Deal found 10/13$206
This Frontier deal was found by Cheapflights users on 10/13. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/294:58 pmISP - DEN
1 stop8h 18mFrontier
Sat 11/111:59 pmDEN - ISP
1 stop7h 03mFrontier
Deal found 10/13$227
This CheapOair deal was found by Cheapflights users on 10/13. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 11/98:57 pmISP - DEN
1 stop28h 19mFrontier
Tue 11/1112:16 amDEN - ISP
1 stop8h 21mFrontier
Deal found 10/13$231
This Frontier deal was found by Cheapflights users on 10/12. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 10/244:58 pmISP - DEN
1 stop8h 18mFrontier
Sat 10/2511:59 pmDEN - ISP
1 stop7h 08mFrontier
Deal found 10/12$250
This CheapOair deal was found by Cheapflights users on 10/12. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 10/1410:39 amISP - DEN
1 stop24h 04mFrontier
Sun 11/212:16 amDEN - ISP
1 stop8h 21mFrontier
Deal found 10/12$252
This CheapOair deal was found by Cheapflights users on 10/13. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 10/204:58 pmISP - DEN
1 stop21h 46mFrontier
Tue 10/2112:36 amDEN - ISP
1 stop8h 21mFrontier
Deal found 10/13$277
This CheapOair deal was found by Cheapflights users on 10/14. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/224:58 pmISP - DEN
1 stop8h 18mFrontier
Thu 10/2312:36 amDEN - ISP
1 stop8h 01mFrontier
Deal found 10/14$284
This Kiwi.com deal was found by Cheapflights users on 10/13. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 10/286:27 pmISP - DEN
1 stop30h 49mMultiple Airlines
Sat 11/111:59 pmDEN - ISP
2 stops10h 01mMultiple Airlines
Deal found 10/13$285
This CheapOair deal was found by Cheapflights users on 10/13. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 11/74:58 pmISP - DEN
1 stop8h 18mFrontier
Sun 11/912:16 amDEN - ISP
1 stop8h 21mFrontier
Deal found 10/13$302

Cheap flight deals from Islip to Colorado

Keep the following information in mind while searching for Islip to Colorado flight deals. Data was last updated October 14, 2025.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$155
(CheapOair)

One-way from

$86
(CheapOair)

Popular in

December

Cheapest in

January

Average price

$282
Provider with most accurate pricing for New York (NYC)-Denver Intl flight deals.
Search Deals
Provider most trusted by Cheapflights users for New York (NYC)-Denver Intl flights.
Search Deals
From Islip Long Island to Colorado
Search Deals
One-way flight from Islip Long Island to Colorado
Search Deals
High demand for flights, 3% potential price rise
Search Deals
Cheapest flight prices on average. 1% potential price decrease ($5 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in October 2025
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Cheapflights Fare Finder

 
Customize your flight search to find flights from Islip to Colorado 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 October 14, 2025.
Use the filters below to find and compare flights from Islip to Colorado that are best for you.

Fly from

Islip

Fly to

Colorado

Route

Depart

Return

Price

IslipDenver

ISP - DEN

ISPDEN

Islip Long Island

Thu 10/30

6:37 pm-8:15 am

1 stop15h 38m

Denver Intl

Sun 11/2

11:59 pm-9:09 am

1 stop7h 10m

$155

IslipDenver

ISP - DEN

ISPDEN

Islip Long Island

Sun 11/16

8:49 am-8:43 am

1 stop25h 54m

Denver Intl

Tue 11/18

12:16 am-10:37 am

1 stop8h 21m

$206

IslipDenver

ISP - DEN

ISPDEN

Islip Long Island

Wed 10/29

4:58 pm-11:16 pm

1 stop8h 18m

Denver Intl

Sat 11/1

11:59 pm-9:02 am

1 stop7h 03m

$227

IslipDenver

ISP - DEN

ISPDEN

Islip Long Island

Sun 11/9

8:57 pm-11:16 pm

1 stop28h 19m

Denver Intl

Tue 11/11

12:16 am-10:37 am

1 stop8h 21m

$231

IslipDenver

ISP - DEN

ISPDEN

Islip Long Island

Fri 10/24

4:58 pm-11:16 pm

1 stop8h 18m

Denver Intl

Sat 10/25

11:59 pm-9:07 am

1 stop7h 08m

$250

IslipDenver

ISP - DEN

ISPDEN

Islip Long Island

Mon 10/20

4:58 pm-12:44 pm

1 stop21h 46m

Denver Intl

Tue 10/21

12:36 am-10:57 am

1 stop8h 21m

$277

IslipDenver

ISP - DEN

ISPDEN

Islip Long Island

Wed 10/22

4:58 pm-11:16 pm

1 stop8h 18m

Denver Intl

Thu 10/23

12:36 am-10:37 am

1 stop8h 01m

$284

IslipDenver

ISP - DEN

ISPDEN

Islip Long Island

Fri 10/31

4:58 pm-9:00 am

1 stop18h 02m

Denver Intl

Sat 11/1

12:16 am-8:42 pm

1 stop19h 26m

$284

IslipDenver

ISP - DEN

ISPDEN

Islip Long Island

Tue 10/28

6:27 pm-11:16 pm

1 stop30h 49m

Denver Intl

Sat 11/1

11:59 pm-12:00 pm

2 stops10h 01m

$285

IslipDenver

ISP - DEN

ISPDEN

Islip Long Island

Sat 11/15

11:40 am-8:43 am

1 stop23h 03m

$86

Flights are sorted by cheapest round-trip flights first.

Deals found on 10/13

Showing 1-10 of 20 results
1
2

Best time to book a flight from Islip to Colorado

Have a flexible travel schedule? Discover the best time to fly to Colorado 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.

Cheapflights Insights

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

What is the cheapest month to book a flight from Islip to Colorado?

Currently, November is the cheapest month in which you can book a flight from Islip to Colorado (average of $98). Flying from Islip to Colorado in May is currently the most expensive (average of $143). 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.

What is the cheapest time of day to fly from ISP to CO?

Find hourly flight availability from Islip to Colorado. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated October 14, 2025.

It’s optimal to fly from Islip to Colorado in the evening. By choosing this option you can save up to 63% on the cost of your flight, compared to a flight at noon.

Reviews of airlines servicing Colorado

Get insights into the airlines that provide service to Colorado. 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 Colorado. Reviews last updated October 14, 2025.
Peruse reviews from past customers who have flown with Southwest and Frontier from Islip to Colorado to help guide your decision. Users have also rated airlines in terms of entertainment options, comfort, food, crew/service, and boarding process.
Southwest
8.0
Very good
4,238 reviews

Comfort

8.0

Food

7.0

Boarding

8.1

Crew

8.6

Entertainment

7.5

Overall

8.0

Reviews

1 / 20
2.0
Mediocre

Mike,Aug 2025

OKC - AUS

AC was not adequate, even on a night flight. WiFi subpar even for the airlines
Southwest
8.0
Very good
4,238 reviews
Southwest
8.0
Very good
4,238 reviews

Comfort

8.0

Food

7.0

Boarding

8.1

Crew

8.6

Entertainment

7.5

Overall

8.0

Reviews

1 / 20
2.0
Mediocre

Mike,Aug 2025

OKC - AUS

AC was not adequate, even on a night flight. WiFi subpar even for the airlines
Frontier
5.8
Fair
3,135 reviews
Southwest
8.0
Very good
4,238 reviews

Comfort

8.0

Food

7.0

Boarding

8.1

Crew

8.6

Entertainment

7.5

Overall

8.0

Reviews

1 / 20
2.0
Mediocre

Mike,Aug 2025

OKC - AUS

AC was not adequate, even on a night flight. WiFi subpar even for the airlines

Related info for your journey

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

  • What airport do you fly from for flights from Islip to Colorado?

    If you book a flight to Colorado from Islip, you will be flying from Long Island, which is the city’s only airport. Islip Long Island (ISP) is located 7.2 mi from the center of Islip.

  • How long is the flight from Islip to Colorado?

    Departing from Islip to Colorado will take you 15h 38m. Islip and Colorado are separated by a distance of 1654 mi.

  • What are the most popular routes from Islip to Colorado?

    Most travelers choose Islip Long Island - Denver Intl, Islip Long Island - Montrose County or Islip Long Island - Colorado Springs when deciding on the best route from Islip to Colorado.

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

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

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

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

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

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

    Currently, November is the cheapest month in which you can book a flight from Islip to Colorado (average of $98). Flying from Islip to Colorado in May is currently the most expensive (average of $143). 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

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Top 2 airlines flying from Islip to Colorado

Discover the top 2 airlines that operate flights from Islip to Colorado. 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 October 14, 2025.
AirlineCheapestAverageFlexibilityOn-time
FrontierCheapest$148Average$253FlexibilityNo cancel feeOn-time62%
SouthwestCheapest$388Average$521FlexibilityNo cancel feeOn-time63%

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