$112 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 9/20. 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
Travelers love KAYAK
41,299,237 searches in the past 7 days on KAYAK

Save 22% or moreCompare multiple travel sites with one search.

Track pricesNot ready to book? Create a price alert for when prices drop.

Bundle and saveSave money when you bundle your flight + hotel.

Filter your dealsChoose cabin class, free Wi-Fi and more.

Flights Deals
Booking Insights
Flights Deals

Cheap Flights from Islip to Colorado

Cheapest round-trip prices found by our users on KAYAK in the last 72 hours
Denver
Denver1 stop$216
Denver
Denver1 stop$216

Book Cheap Islip to Colorado Plane Tickets

 
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

Wed, Oct 22 - Sat, Oct 25
Frontier Logo
5:05 pm - 11:16 pmISP-DEN
8h 11m1 stop
Frontier Logo
9:47 am - 7:53 pmDEN-ISP
8h 06m1 stop
$216Frontier
Find Deal
Wed, Oct 22 - Fri, Oct 24
Frontier Logo
5:05 pm - 11:16 pmISP-DEN
8h 11m1 stop
Frontier Logo
12:04 am - 10:37 amDEN-ISP
8h 33m1 stop
$238Frontier
Find Deal
Tue, Aug 12 - Fri, Aug 15
Frontier Logo
4:45 pm - 12:19 pmISP-DEN
21h 34m1 stop
Frontier Logo
12:23 am - 7:42 pmDEN-ISP
17h 19m1 stop
$239Frontier
Find Deal
Tue, Sep 16 - Mon, Sep 22
Frontier Logo
11:25 am - 10:14 amISP-DEN
24h 49m1 stop
Frontier Logo
12:04 am - 10:40 amDEN-ISP
8h 36m1 stop
$245Frontier
Find Deal
Wed, Sep 3 - Sat, Sep 6
Frontier Logo
8:00 am - 8:09 amISP-DEN
26h 09m1 stop
Frontier Logo
11:59 pm - 4:27 pmDEN-ISP
14h 28m1 stop
$247Frontier
Find Deal
Sat, Sep 20 - Thu, Sep 25
Frontier Logo
5:05 pm - 11:13 pmISP-DEN
8h 08m1 stop
Frontier Logo
11:59 pm - 9:04 amDEN-ISP
7h 05m1 stop
$253Frontier
Find Deal
Sat, Sep 20 - Thu, Sep 25
Frontier Logo
5:05 pm - 11:13 pmISP-DEN
8h 08m1 stop
Frontier Logo
11:59 pm - 9:04 amDEN-ISP
7h 05m1 stop
$254Frontier
Find Deal
Sat, Aug 16 - Sun, Aug 17
Frontier Logo
8:37 pm - 8:02 amISP-DEN
13h 25m1 stop
Frontier Logo
11:58 pm - 1:04 pmDEN-ISP
11h 06m1 stop
$258Frontier
Find Deal
Thu, Sep 25 - Tue, Sep 30
Southwest Logo
3:05 pm - 8:05 pmISP-DEN
7h 00m2 stops
Southwest Logo
6:45 am - 3:10 pmDEN-ISP
6h 25m1 stop
$338Southwest
Find Deal
Thu, Sep 25 - Tue, Sep 30
Southwest Logo
3:05 pm - 8:05 pmISP-DEN
7h 00m2 stops
Southwest Logo
11:20 am - 10:05 pmDEN-ISP
8h 45m2 stops
$343Southwest
Find Deal
Booking Insights

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 November, when tickets cost $330 (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 seasonJanuary
Cheapest flight$112
Best time to beat the crowds with an average 1% drop in price.
Most popular time to fly with an average 12% 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.

Reviews of the top airline 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 4241 reviews
8.1Boarding
7.0Food
7.5Entertainment
8.0Comfort
8.6Crew
Airline reviews

southwest just starting charging for luggage. hadnt realized it until it was too late. now out $70 when i couldve bought a carry on if i wouldve known. free bags was one of the only reasons i chose southwest over another airline (the other being no assigned seats, which is apparently also being changed). stupid business decision. wont be flying southwest anymore.

2.0 MediocreAnonymous, Jul 2025AUS - RDU
Read more Southwest reviews

southwest just starting charging for luggage. hadnt realized it until it was too late. now out $70 when i couldve bought a carry on if i wouldve known. free bags was one of the only reasons i chose southwest over another airline (the other being no assigned seats, which is apparently also being changed). stupid business decision. wont be flying southwest anymore.

The quality of Southwest Airlines continues to degrade each time I fly with them. If it were not for the free luggage, I would probably choose another airline. Their prices are a little bit competitive, but way too high for the quality of the service. Southwest is not unique in this way. Domestic flight in the United States of America has continued to be a lower and lower quality product. Very sad when you compare the quality of domestic airlines to that of many international airlines around the world.

Very smooth checking in our luggage with a super pleasant SW agent. I enjoyed a fun entertaining movie.

WiFi did not work. For as outrageous as these flights cost, when they’re advertised with certain services/ features they should be in working order

Worst experience I had on Southwest. Still better than most, but the seating was barely tolerable.

The Southwest employees (all two of them) were very nice and cheerful despite the fact the line to self-check a bag (simply drop it off) was hundreds of people long. Thank God I arrived early to the airport because I stood in this line for at least an hour. Once on the flight that had been delayed by an hour, we had no Wi-Fi and thus no entertainment. Finally, I hope the investor strong arm tactics against Southwest pay off in a short-term windfall to your C-Suite because the rest of you are screwed. I have been a faithful Southwest customer for 15 years due to everything you just got rid of. I'm flying to Idaho and Washington in October, both places I used to simply book with Southwest without a second thought now with Frontier (Washington) and United (Idaho) because they offer everything the "new" Southwest does but cheaper and at better times, destinations, etc. This really makes me sad...

It was one and half hour late... Not sure if any other experience matters.

Flights delayed by 4-6 hours. Boarding was a mess and unclear. Bags were not at arrival airport and had never even been put on the plane. No idea when I’ll get them. Don’t fly into Denver!

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.

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

Information on your arrival and departure airports

Not what you’re looking for? Find thousands of other hotels, flights, car rentals and package deals with KAYAK.