$168 Find Cheap Flights from Islip to Colorado

This is the cheapest one-way flight price found by a KAYAK user in the last 72 hours by searching for a flight from Islip to Colorado departing on 9/29. 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

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

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

Cheapest round-trip prices found by our users on KAYAK in the last 72 hours
Denver
Denver2 stops$302
Denver
Denver2 stops$302

Cheap Flights from Islip to Colorado

 
Here are some of the best deals found on KAYAK recently from the most popular airlines for round-trip flights from Islip to Colorado 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 Islip to Colorado

Mon, Dec 8 - Thu, Dec 11
Southwest Logo
5:40 am - 1:55 pmISP-DEN
10h 15m2 stops
Southwest Logo
7:00 am - 3:20 pmDEN-ISP
6h 20m1 stop
$302Southwest
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Mon, Dec 8 - Thu, Dec 11
Southwest Logo
5:40 am - 1:55 pmISP-DEN
10h 15m2 stops
Southwest Logo
10:35 am - 10:05 pmDEN-ISP
9h 30m2 stops
$307Southwest
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Mon, Dec 8 - Thu, Dec 11
Southwest Logo
12:55 pm - 6:00 pmISP-DEN
7h 05m1 stop
Southwest Logo
7:00 am - 3:20 pmDEN-ISP
6h 20m1 stop
$334Southwest
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Thu, Oct 16 - Sun, Oct 19
Southwest Logo
5:35 pm - 11:00 pmISP-DEN
7h 25m1 stop
Southwest Logo
11:40 pm - 12:00 pmDEN-ISP
10h 20m1 stop
$339Southwest
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Thu, Aug 14 - Wed, Aug 20
Frontier Logo
2:05 pm - 11:56 pmISP-DEN
11h 51m1 stop
Frontier Logo
11:59 pm - 12:09 pmDEN-ISP
10h 10m1 stop
$340Frontier
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Tue, Aug 12 - Sat, Aug 23
Southwest Logo
5:30 am - 5:55 pmISP-DEN
14h 25m1 stop
Southwest Logo
11:50 am - 9:40 pmDEN-ISP
7h 50m1 stop
$348Southwest
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Tue, Aug 12 - Sat, Aug 23
Southwest Logo
5:30 am - 5:55 pmISP-DEN
14h 25m1 stop
Southwest Logo
9:40 am - 9:40 pmDEN-ISP
10h 00m2 stops
$354Southwest
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Mon, Aug 11 - Tue, Aug 12
Southwest Logo
6:25 am - 2:00 pmISP-DEN
9h 35m1 stop
Southwest Logo
6:45 am - 3:10 pmDEN-ISP
6h 25m1 stop
$362Southwest
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Sat, Oct 11 - Sat, Oct 18
Frontier Logo
5:05 pm - 11:16 pmISP-DEN
8h 11m1 stop
Frontier Logo
9:47 am - 7:53 pmDEN-ISP
8h 06m1 stop
$369Frontier
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Wed, Sep 10 - Thu, Sep 18
Southwest Logo
5:30 am - 12:15 pmISP-DEN
8h 45m1 stop
Southwest Logo
12:20 pm - 10:45 pmDEN-ISP
8h 25m1 stop
$371Southwest
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KAYAK's insights & trends for Islip to Colorado flights

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

What is the cheapest month to fly from Islip to Colorado?

To calculate monthly average prices, KAYAK takes all prices for each month over the last year for round-trip flights from Islip to Colorado, removes the top 0.1% to account for outliers, and then takes the median of all values for each month.

The cheapest month for flights from Islip to Colorado is December, when tickets cost $148 (return) on average. On the other hand, the most expensive months are April and March, when the average cost of round-trip tickets is $631 and $611 respectively.

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

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

For Islip to Colorado, Wednesday is the cheapest day to fly on average and Friday is the most expensive. Flying from Colorado back to Islip, the best deals are generally found on Thursday, with Wednesday being the most expensive.


Good to know

Low seasonDecember
High seasonMay
Cheapest flight$168
Best time to beat the crowds with an average 67% drop in price.
Most popular time to fly with an average 18% increase in price.
Flight from Islip to Denver

FAQs - booking Colorado flights

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

    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 Islip to Colorado.

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

    KAYAK’s flight Price Forecast tool uses historical data to determine whether the price for a flight from Islip to Colorado 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 Islip to Colorado?

    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 from Islip to Colorado with an airline and back with another airline.

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

    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 from Islip to Colorado up to 3 days before/after your preferred dates. You can then pick the flights that suit you best.

  • What is the cheapest time of day to fly to Colorado?

    The cheapest time of day to fly to Colorado is generally at night, when round-trip flights cost $148 on average. Morning departures are around 12% cheaper than evening flights, on average. The most expensive time of day to fly to Colorado is generally in the evening, which is peak travel time and where the average cost of a ticket is $268.

Top airlines flying from Islip to Colorado

 
See real verified KAYAK customer reviews for airlines flying from Islip to Colorado. 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 Islip to Colorado? 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 4287 reviews
7.6Entertainment
8.0Comfort
7.1Food
8.2Boarding
8.6Crew
Airline reviews

Southwest is typically delayed, and it gets wearisome. It is no longer a discount airline and you get way less than you pay for when it comes to comfort and Ce.

6.0 GoodDavid, Jun 2025BWI - COS
Read more Southwest reviews

Southwest is typically delayed, and it gets wearisome. It is no longer a discount airline and you get way less than you pay for when it comes to comfort and Ce.

We sat on the plane on the tarmac for 4 hours.

I'm not a fan of Southwest's model. I don't like the herding style of boarding.

Flight crew and cabin crew were great. I had to rearrange flights because my original flight was 3hrs delayed for weather, the rub is the flight I moved to boarded on time then we sat at the gate for 2 hours because scheduling stole our first officer for another flight, TWICE. Then our actual FO was an hour delayed. To make it worse my original flight went from a 3 hour delay to departing 15min EARLY. Just poor scheduling operations all around.

Bring back peanuts Take our drink orders when were all seated, especially after you switch to assigned seating.

After a 3 hour layover in Denver my flight was delayed over 5 hours! No explanation; no assistance; no offer to provide compensation; no one at Southwest was willing to offer any assistance. 8 hours in the Denver airport - ridiculous!

WiFi on the flight was not working. Thus, entertainment options were limited.

I really like open seating. I hate that I've heard this is going away. This is one of the unique things that makes Southwest my goto choice.

It was 2 hours 45 minutes late, for no apparently clear reason.

It went well. Plane wasn't full. Will be great when assigned seating is in place

I liked the turn-style feature at gate 209B at LAX. Very efficient process. The gate staff also made several, clearly directed announcements so I felt very informed.

Seats are uncomfortable but price is good. Guess I can put up with misery for four hours.

The plane failed preflight inspection, so we sat there for 90 mins while they tried to fix it. Ultimately, everything was remedied and we made our connecting flight; instead of a 2 hour layover at the airport, we spent it waiting on the plane.

I loked walking out on the tarmac to board and no first class. I didn't like that they have no snacks or onboard wifi to bide your time.

The seats were extremely hard and uncomfortable. It was disappointing even for a budget airline.

Delayed each time on a round trip with no significant weather interference. Updates to flight times came after the fact. 30 min behind in boarding and board and phone still show an on time departure. Some mysterious extra 300 miles that came so surprising they had to fuel while we were already on board?

Our flight was canceled for no known reason. We weren’t told until we were checking in at 5:00 am. This was after our last flight with Frontier where we sat on the plane for three hours (not an exaggeration) before we took off because of a mechanical issue. We won’t be flying Frontier again.

Allowed me to chose my seat without extra charge (I purchased full-price ticket) and boarding was in group1. Didn't even serve water.

Stuck in Phoenix for two days, not even a hotel voucher offered.

Every day about it was very different all the boarding pass where all wrong l miss flight no refund all crazy

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

Information on your arrival and departure airports

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