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Islip

$125+ Cheap flights from Denver to Islip, NY (DEN - 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 9/6. Fares are subject to change and may not be available on all flights or dates of travel.
DEN — ISP
Jun 17 — Jun 241
Tue 6/17
Tue 6/24
1 adult, Economy
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Cheap flight deals from Denver to Islip

Discover tips and strategies to find the most affordable flight options for your journey from Denver (DEN) 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 June 12, 2025.

Round-trip from

$346
(CheapOair)

One-way from

$125
(CheapOair)

Popular in

December

Cheapest in

August

Average price

$428
From Denver Intl to Islip Long Island
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One-way flight from Denver Intl to Islip Long Island
Search Deals
Highest demand for flights based on searches. 12% potential increase in price ($60 potential increase over avg. RT price).
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Cheapest flight prices on average. 6% potential price decrease ($26 potential savings vs. average RT price).
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Average for round-trip flights in June 2025
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Find flight deals from Denver to Islip

Cheapest flights from Denver to Islip
Explore the most affordable flight options available from Denver to Islip. Find the lowest fares from popular airlines and budget airlines, with prices last updated on June 12, 2025.

This CheapOair deal was found by Cheapflights users on 6/9. 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 9/188:32 amDEN - ISP
1 stop24h 05mFrontier
Mon 9/225:07 pmISP - DEN
1 stop18h 01mFrontier
Deal found 6/9$249
This Southwest deal was found by Cheapflights users on 6/10. 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 9/2512:20 pmDEN - ISP
1 stop8h 25mSouthwest
Sat 9/273:40 pmISP - DEN
1 stop7h 30mSouthwest
Deal found 6/10$343

Cheapflights Fare Finder

Customize your flight search to find flights from Denver 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 June 12, 2025.
Use the filters below to find and compare flights from Denver to Islip that are best for you.

Fly from

Denver

Fly to

Islip

Route

Depart

Return

Price

DenverIslip

DEN - ISP

DENISP

Denver Intl

Thu 9/18

8:32 am-10:37 am

1 stop24h 05m

Islip Long Island

Mon 9/22

5:07 pm-9:08 am

1 stop18h 01m

$249

DenverIslip

DEN - ISP

DENISP

Denver Intl

Thu 9/25

12:20 pm-10:45 pm

1 stop8h 25m

Islip Long Island

Sat 9/27

3:40 pm-9:10 pm

1 stop7h 30m

$343

DenverIslip

DEN - ISP

DENISP

Denver Intl

Sat 9/6

12:04 am-10:37 am

1 stop8h 33m

$125

DenverIslip

DEN - ISP

DENISP

Denver Intl

Thu 6/26

8:00 am-10:10 pm

2 stops12h 10m

$274

DenverIslip

DEN - ISP

DENISP

Denver Intl

Wed 6/25

11:59 pm-10:04 am

2 stops32h 05m

$462

Flights are sorted by cheapest round-trip flights first.

Deals found on 6/9

Best time to book a flight from Denver to Islip

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

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

Currently, January is the cheapest month in which you can book a flight from Denver to Islip, New York (average of $108). Flying from Denver to Islip, New York in November is currently the most expensive (average of $213). 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 DEN to ISP?

Find hourly flight availability from Denver to Islip. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated June 12, 2025.

Unlike in the morning, when flights are generally more expensive, you can save up to 27% on flights from Denver to Islip, New York by exploring options for tickets at noon.

Rainfall in Islip by month

Plan your trip to Islip by taking into account the average rainfall totals by month.

In terms of precipitation, rainfall in Islip, New York ranges from 3.3 - 4.4 inches per month. March is typically the wettest month, when rainfall can reach 4.4 in. February is typically the driest time to visit Islip, New York when rainfall is around 3.3 in.

Temperature in Islip by month

Plan your trip to Islip by taking into account the average temperature totals by month.

If weather is an important factor for your trip to Islip, New York, use this chart to help with planning. For those seeking warmer temperatures, July is the ideal time of year to visit, when temperatures reach an average of 73.4 F. Travelers looking to avoid the cold should look outside of January, when temperatures are typically at their lowest (around 30.2 F).

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 June 12, 2025.
Breeze Airways
8.1
Very good
178 reviews

Food

6.7

Entertainment

6.6

Boarding

8.3

Overall

8.1

Comfort

8.2

Crew

8.8

Reviews

1 / 11
10.0
Excellent

Dena,Dec 2024

LAS - BDL

It was comfortable and the crew was great! A few free snacks offered would be nice!
Breeze Airways
8.1
Very good
178 reviews
Breeze Airways
8.1
Very good
178 reviews

Food

6.7

Entertainment

6.6

Boarding

8.3

Overall

8.1

Comfort

8.2

Crew

8.8

Reviews

1 / 11
10.0
Excellent

Dena,Dec 2024

LAS - BDL

It was comfortable and the crew was great! A few free snacks offered would be nice!
Southwest
8.0
Very good
4,287 reviews
Breeze Airways
8.1
Very good
178 reviews

Food

6.7

Entertainment

6.6

Boarding

8.3

Overall

8.1

Comfort

8.2

Crew

8.8

Reviews

1 / 11
10.0
Excellent

Dena,Dec 2024

LAS - BDL

It was comfortable and the crew was great! A few free snacks offered would be nice!
Frontier
6.0
Okay
3,295 reviews
Breeze Airways
8.1
Very good
178 reviews

Food

6.7

Entertainment

6.6

Boarding

8.3

Overall

8.1

Comfort

8.2

Crew

8.8

Reviews

1 / 11
10.0
Excellent

Dena,Dec 2024

LAS - BDL

It was comfortable and the crew was great! A few free snacks offered would be nice!

Related info for your journey

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

  • What are the cheapest airlines flying from Denver to Islip, New York round-trip?

    Frontier, at $346, was found to be the cheapest airline from Denver to Islip, New York. An alternate airline flying to your destination would be Southwest. Frontier is 18% cheaper than the average price of flights available within the next 90 days to this destination.

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

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

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

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

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

    Yes. Cheapflights offers flight deals from Denver 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 Denver to Islip, New York?

    Currently, January is the cheapest month in which you can book a flight from Denver to Islip, New York (average of $108). Flying from Denver to Islip, New York in November is currently the most expensive (average of $213). 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 Denver?

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Alternative routes for Denver to Islip

See prices for flight routes from nearby airports that may be better suited for you.
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Top 2 airlines flying from Denver to Islip

Discover the top 2 airlines that operate flights from Denver 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 June 12, 2025.
AirlineCheapestAverageFlexibilityOn-time
FrontierCheapest$155Average$264FlexibilityNo cancel feeOn-time62%
SouthwestCheapest$375Average$456FlexibilityNo cancel feeOn-time63%

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