DEN - ISP

$65 Find Cheap Flights from Denver to Islip

This is the cheapest one-way flight price found by a KAYAK user in the last 72 hours by searching for a flight from Denver to Islip departing on 12/3. Fares are subject to change and may not be available on all flights or dates of travel. Click the price to replicate the search for this deal.
1 adult
1 adult, Economy, 0 bags

KAYAK searches hundreds of travel sites at once for deals on flights to Islip

 
These are the airlines KAYAK users have selected most often from within our search results in flight searches from Denver to Islip, as well as popular online travel agencies
These are the airlines KAYAK users have selected most often from within our search results in flight searches from Denver to Islip, as well as popular online travel agencies
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Flight Deals

Cheap Flights from Denver to Islip (DEN-ISP)

 
Here are some of the best deals found on KAYAK recently from the most popular airlines for round-trip flights from Denver to Islip that are departing in the next months. While these flights were available on KAYAK in the last 72 hours, prices and availability are subject to change and deals may expire.
Discover the best prices for you by selecting your travel dates on KAYAK.

Recent round-trip flight deals from Denver to Islip

Thu, Nov 13 - Tue, Nov 18
Frontier Logo
6:00 am - 8:54 amDEN-ISP
24h 54m1 stop
Frontier Logo
6:27 pm - 11:16 pmISP-DEN
30h 49m1 stop
$130Frontier
Find Deal
Sun, Nov 16 - Thu, Nov 20
Frontier Logo
6:00 am - 9:09 amDEN-ISP
25h 09m1 stop
Frontier Logo
10:02 am - 8:19 amISP-DEN
24h 17m1 stop
$137Frontier
Find Deal
Wed, Nov 12 - Thu, Nov 13
Frontier Logo
7:45 am - 9:09 amDEN-ISP
23h 24m1 stop
Frontier Logo
6:37 pm - 8:15 amISP-DEN
15h 38m1 stop
$150Frontier
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Fri, Nov 14 - Mon, Nov 17
Frontier Logo
12:16 am - 10:37 amDEN-ISP
8h 21m1 stop
Frontier Logo
9:54 am - 9:58 amISP-DEN
26h 04m1 stop
$170Frontier
Find Deal
Sun, Nov 16 - Wed, Nov 19
Frontier Logo
12:16 am - 10:37 amDEN-ISP
8h 21m1 stop
Frontier Logo
4:58 pm - 11:16 pmISP-DEN
8h 18m1 stop
$176Frontier
Find Deal
Sun, Nov 9 - Thu, Nov 13
Frontier Logo
11:59 pm - 9:09 amDEN-ISP
7h 10m1 stop
Frontier Logo
9:54 am - 8:43 amISP-DEN
24h 49m1 stop
$182Frontier
Find Deal
Fri, Dec 5 - Mon, Dec 8
Frontier Logo
6:31 pm - 9:13 amDEN-ISP
12h 42m1 stop
Frontier Logo
6:00 am - 9:10 amISP-DEN
29h 10m1 stop
$186Frontier
Find Deal
Thu, Dec 11 - Mon, Dec 15
Frontier Logo
11:00 pm - 11:59 pmDEN-ISP
22h 59m1 stop
Frontier Logo
10:19 am - 11:04 pmISP-DEN
14h 45m1 stop
$196Frontier
Find Deal
Wed, Dec 10 - Fri, Dec 12
Southwest Logo
7:00 am - 3:20 pmDEN-ISP
6h 20m1 stop
Southwest Logo
5:50 am - 12:15 pmISP-DEN
8h 25m2 stops
$408Southwest
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Fri, Dec 5 - Mon, Dec 8
Southwest Logo
10:20 am - 10:05 pmDEN-ISP
9h 45m2 stops
Southwest Logo
5:40 am - 1:55 pmISP-DEN
10h 15m2 stops
$413Southwest
Find Deal

Everything you should know

Top airlines
Frontier
Cheapest • from $130 (round-trip)
Southwest
Best reviews • 8.0 score
Airline reviews
Airline reviews
+1
+1
Airline reviews
Airline reviews
+1
Cheapest round-trip
$130
Frontier
Thu 11/13Tue 11/18
DEN - ISP • 1 stop
Cheapest one-way
$65
Frontier
Wed 12/3
DEN - ISP • 1 stop
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KAYAK searches 100s of sites at once to find you the best travel deals.
We hope you love your trip to Islip!
Booking Insights

KAYAK's insights & trends for Denver to Islip flights

Get data-powered insights and trends into flights from Denver to Islip to help you find the cheapest flights, the best time to fly and much more.

What’s the cheapest day of the week to fly from Denver to Islip?

The average price of all round-trip flights from Denver to Islip clicked on KAYAK for each day over the last 12 months.

If you are looking for a flight deal from Denver to Islip, look for departures on Thursdays and avoid leaving on a Wednesday, as it's usually the priciest day. When flying back from Islip, Wednesday is the cheapest day to fly and Friday is the most expensive.

Good to know

Cheapest flight$65
Flight from Denver to Islip

When to book flights from Denver to Islip

Are your dates flexible? Find out the best times to travel from Denver to Islip based on our flight data from the last year. Discover the cheapest month and even day to fly.
Estimated round-trip price
KAYAK looks at all historical flight data for each date to provide a predicted price for one-way trips or round-trips with a duration up to 40 days. While we try to provide actual minimum prices for each date, some prices are predictions and actual prices may differ.

FAQs for booking flights from Denver to Islip

  • What is the cheapest flight from Denver to Islip?

    In the last 3 days, the lowest price for a flight from Denver to Islip was $65 for a one-way ticket and $130 for a round-trip.

  • Do I need a passport to fly between Denver and Islip?

    Even though you are not required to have a passport, keep in mind that an official ID is needed to board the airplane.

  • Which airports will I be using when flying from Denver to Islip?

    When flying out of Denver you will be using Denver Intl. You will be landing at Islip, also known as Islip Long Island.

  • Which aircraft models fly most regularly from Denver to Islip?

    We unfortunately don’t have that data for this specific route.

  • How does KAYAK find such low prices on flights from Denver to Islip?

    KAYAK is a travel search engine. That means we look across the web to find the best prices we can find for our users. With over 2 billion flight queries processed yearly, we are able to display a variety of prices and options on flights from Denver to Islip.

  • How does KAYAK's flight Price Forecast tool help me choose the right time to buy my flight ticket from Denver to Islip?

    KAYAK’s flight Price Forecast tool uses historical data to determine whether the price for a flight to Islip from Denver is likely to change within 7 days, so travelers know whether to wait or book now.

  • What is the Hacker Fare option on flights from Denver to Islip?

    Hacker Fares allow you to combine one-way tickets in order to save you money over a traditional round-trip ticket. You could then fly to Islip with an airline and back to Denver with another airline. Booking your flights between Denver and ISP can sometimes prove cheaper using this method.

  • What is KAYAK's "flexible dates" feature and why should I care when looking for a flight from Denver to Islip?

    Sometimes travel dates aren't set in stone. If your preferred travel dates have some wiggle room, flexible dates will show you all the options when flying to Islip from Denver up to 3 days before/after your preferred dates. You can then pick the flights that suit you best.

Reviews of the top airline flying from Denver to Islip

 
See real verified KAYAK customer reviews for airlines flying from Denver to Islip. Airline scores are aggregated from all reviews left by passengers on KAYAK after flying with an airline. KAYAK doesn’t show reviews that are older than 5 years. Learn how KAYAK collects reviews.
Need help choosing which airline to fly with from Denver to Islip? KAYAK airline reviews give an overall score for each airline based on loads of factors, including comfort, boarding, in-flight entertainment and more, to make your decision easier. See airline scores according to verified KAYAK customer reviews.
8.0
SouthwestOverall score based on 4243 reviews
7.5Entertainment
8.1Boarding
7.0Food
8.6Crew
8.0Comfort
Airline reviews

Ever since Southwest starting charging for bags, passengers don't want to pay to check their bags, so the gate agents have to beg people to check their roller bags now because there's "not enough space". This was a terrible business move by Southwest.

8.0 ExcellentGreg, Oct 2025OAK - BUR
Read more Southwest reviews

Ever since Southwest starting charging for bags, passengers don't want to pay to check their bags, so the gate agents have to beg people to check their roller bags now because there's "not enough space". This was a terrible business move by Southwest.

Full cans of soda would be nice. A choice between two snacks would be appreciated.

Tried watching free movie and it kept freezing so I couldn’t finish.

All was good. I just had a hard time getting connected to the WiFi/internet during the flight

Sacrament staff are always polite and helpful. Airport is easy to maneuver and boarding is straightforward.

Great flight. Outstanding Service. Southwest was able to put us on a direct flight to Denver when the connection could have been affected by a later arrival to Baltimore. The direct flight was less expensive that the flight with the connection in Baltimore.

Delays delays delays. Late taking off, late landing, wait for a gate, etc.

Boarded on time but once we were ready for take off, the crew determined that, although every seat was taken, somehow someone was on the wrong flight. Delay, delay delay, announcements and ended up with one person checking EVERY ID against their passenger Manifest only to figure out it was a "clerical error." We departed 54 minutes late causing me to run in the St. Louis Airport to make my connection and lose the priority boarding spot I had paid for. Unnecessary delay.

I was re-booked onto another flight because my original flight was delayed and I would have missed my connector. I ended up in the “C” group after paying extra to be in the “A “ group on the original flight. At least if you’re going to re-book people, re-book them into the same group.

Flight was delayed due to plane not passing inspection And one of the crew had to time out and we had to wait for another one A 3 hour delay

Everything you need to know for your flight from Denver to Islip

Information on your arrival and departure airports

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