$174 Find Cheap Flights from Islip to Colorado - Compare and Save

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 6/30. 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 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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Cheap Flights from Islip to Colorado

Cheapest round-trip prices found by our users on KAYAK in the last 72 hours
Denver
Denver1 stop$242
Colorado Springs
Colorado Springs2 stops$557
Montrose
Montrose2 stops$688
Denver
Denver1 stop$242
Colorado Springs
Colorado Springs2 stops$557
Montrose
Montrose2 stops$688

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

Tue, Sep 1 - Wed, Sep 2
Frontier Logo
4:41 pm - 10:54 pm
ISP
-
DEN
8h 13m
1 stop
Frontier Logo
11:49 pm - 10:03 am
DEN
-
ISP
8h 14m
1 stop
$242Frontier
Thu, Aug 27 - Sun, Aug 30
Frontier Logo
7:46 pm - 2:44 pm
ISP
-
DEN
20h 58m
1 stop
Frontier Logo
11:59 pm - 7:01 pm
DEN
-
ISP
17h 02m
1 stop
$275Frontier
Tue, Sep 1 - Wed, Sep 2
Frontier Logo
4:41 pm - 10:54 pm
ISP
-
DEN
8h 13m
1 stop
Frontier Logo
11:49 pm - 10:03 am
DEN
-
ISP
8h 14m
1 stop
$290Frontier
Fri, Aug 21 - Tue, Aug 25
Frontier Logo
10:48 am - 10:54 pm
ISP
-
DEN
14h 06m
1 stop
Frontier Logo
9:15 am - 10:03 am
DEN
-
ISP
22h 48m
1 stop
$299Frontier
Fri, Aug 7 - Sat, Aug 15
Frontier Logo
10:57 am - 11:00 pm
ISP
-
DEN
14h 03m
1 stop
Frontier Logo
6:00 am - 7:01 pm
DEN
-
ISP
11h 01m
1 stop
$305Frontier
Fri, Aug 28 - Fri, Sep 4
Frontier Logo
10:48 am - 10:54 pm
ISP
-
DEN
14h 06m
1 stop
Frontier Logo
11:49 pm - 10:03 am
DEN
-
ISP
8h 14m
1 stop
$308Frontier
Wed, Sep 23 - Sat, Sep 26
Frontier Logo
4:13 pm - 11:04 pm
ISP
-
DEN
8h 51m
1 stop
Frontier Logo
11:59 pm - 9:33 am
DEN
-
ISP
7h 34m
1 stop
$314Frontier
Thu, Sep 3 - Wed, Sep 9
Frontier Logo
10:48 am - 10:54 pm
ISP
-
DEN
14h 06m
1 stop
Frontier Logo
11:59 pm - 9:33 am
DEN
-
ISP
7h 34m
1 stop
$320Frontier
Mon, Jul 13 - Sun, Jul 19
Southwest Logo
12:30 pm - 9:50 pm
ISP
-
COS
11h 20m
2 stops
Southwest Logo
5:00 am - 4:40 pm
COS
-
ISP
9h 40m
2 stops
$557Southwest
Mon, Jul 20 - Fri, Jul 24
Southwest Logo
12:30 pm - 7:35 pm
ISP
-
MTJ
9h 05m
2 stops
Southwest Logo
8:00 am - 11:40 pm
MTJ
-
ISP
13h 40m
2 stops
$688Southwest
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.

How much is a round-trip flight from Islip, New York to Colorado?

This analysis is based on the cheapest round-trip price found on KAYAK in the last 12 months by searching for a flight from Islip, New York to Colorado departing in September.

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 January, when tickets cost $0 (return) on average. On the other hand, the most expensive months are July and November, when the average cost of round-trip tickets is $772 and $462 respectively.

Find deals

Good to know

Low seasonSeptember
Cheapest flight$174
Best time to beat the crowds with an average 30% drop in price.
Most popular time to fly and prices are also 11% lower on average.
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.

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.
7.9
SouthwestOverall score based on 4235 reviews
7.0Food
8.6Crew
8.1Boarding
7.5Entertainment
8.0Comfort
Airline reviews

Flight was delayed, full flight and I had to change gates. Southwest flights are always late later in the day.

4.0 OkaySteven, Jun 2026
ONT - LAS
Read more Southwest reviews

Flight was delayed, full flight and I had to change gates. Southwest flights are always late later in the day.

Flight was delayed over 3 hours. Planes were dirty. Staff indifferent. And they serve vegan pretzels as snacks.

It was great. The gate staff were very helpful in Portland when my son forgot his rolling bag and had to go back to get it just in time to make it on the plane. We really appreciate that. Great job!

Airline is not very senior friendly. Flights are late, forcing us to run to the connecting flight. Food is awful. Wish they would go back to pretzels and peanuts. During flight, pressurization isn’t quite right and all of our ears get plugged. Everything is nickel and dime, charging for boarding, seat selection and legroom. While a screen at the desk in the gate area says check your roll on bag now for free due to space limitation, the employee at the desk will not check the bag without a $100 fee. Insane.

Kayak could’ve posted the correct gate number. Almost missed my flight.

Slow boarding, limited food and drink portions. Bad delays and turbulence

there were two flight attendants that were up front...that were the best! They get KUDOs for making my trip only fantastic. Tell them Jeff said that!

OKay. I sat in the back of the plane and it was really loud between babies and little kids, and adults who.like to talk a lot and loudly most of the flight.

Flight coming out of Buffalo was delayed, so we had to be rescheduled on another flight from Baltimore to Phoenix which means we had a long layover and got home 3.5 hours late. Shuttle to parking stopped at 10pm, so we had to pay for an Uber to the parking lot and got charged an extra day of parking since it was after midnight. Not the best experience. Long day!

Was fine, delayed and feels like southwest is always late

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

Information on your arrival and departure airports

Islip (ISP)