What airlines fly to Colorado?

Frontier, United Airlines and Southwest are the top three most popular airlines that fly to Colorado from Ontario according to our data. Frontier is the first choice among our users, with 49% of people opting to fly with this airline when traveling to Colorado. Keep in mind that there are 8 different airlines that fly to Colorado on a routine basis, so you have a few additional options to choose from.

What is the cheapest airline that flies from Ontario to Colorado?

Frontier, Southwest, and American Airlines are the most popular carriers operating from Ontario to Colorado

How many flights depart from Ontario to Colorado on average per week?

60 flights are operational weekly from Ontario to Colorado as of September 2025. The most popular departure day for this route is Mon, with 18% of flights per week taking off on this day.

How many flights depart from Ontario to Colorado on average per day?

The number of flights available between Ontario and Colorado is 8 per day as of September 2025. The most frequent departure time is 5:00AM, with 36% of daily flights leaving in the afternoon.

When did momondo last update prices for flights from Ontario Airport to Colorado?

Prices for flights from Ontario Airport to Colorado refresh daily.

How many operators does momondo search for flights from Ontario Airport to Colorado?

As of September 2025, there are 5 operators available to choose from for flights from Ontario Airport to Colorado.

How old do you have to be to fly from Ontario Airport to Colorado?

The minimum age for a child to fly alone is five, but airlines offering an unaccompanied minor (UNMR) service may have their age restrictions, such as regulations concerning flight duration, timing, and layovers. It is recommended that you verify with the airline you are booking with for travel from Ontario Airport to Colorado.

What documentation or ID do you need to fly to Colorado?

The travel and health documents required for your trip to Colorado can vary based on your itinerary and personal situation. As a rule, consider having multiple documents such as a national ID card or driver’s license, and a passport valid for six-months after you plan to arrive at Colorado. We always recommend checking with your airline or a trusted third party such as IATA to get advice.

$51 Cheap Flights from Ontario to Colorado in 2025/26

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Find the cheapest flights from Ontario to Colorado

Round-trip

One-way

Last minute

Direct

Cheap round-trip flights

11:52 am - 3:14 pmONT-DEN

2h 22mnonstop

9:30 am - 10:57 amDEN-ONT

2h 27mnonstop

$67Frontier

Find Deal

Fri, Dec 5 - Mon, Dec 15

7:04 am - 10:31 amONT-DEN

2h 27mnonstop

10:29 pm - 11:50 pmDEN-ONT

2h 21mnonstop

$68Frontier

Find Deal

Tue, Oct 14 - Sat, Oct 18

5:55 pm - 12:35 amONT-COS

5h 40m1 stop

6:15 pm - 11:40 pmCOS-ONT

6h 25m1 stop

$177Southwest

Find Deal

Mon, Oct 13 - Mon, Oct 20

2:20 pm - 9:10 pmONT-COS

5h 50m1 stop

6:00 am - 12:45 pmCOS-ONT

7h 45m2 stops

$182Southwest

Find Deal

Wed, Oct 22 - Sat, Oct 25

9:50 am - 5:09 pmONT-COS

6h 19m1 stop

5:49 pm - 11:39 pmCOS-ONT

6h 50m1 stop

$217Delta

Find Deal

Sat, Oct 11 - Tue, Oct 14

6:27 pm - 11:52 pmONT-COS

4h 25m1 stop

1:54 pm - 10:52 pmCOS-ONT

9h 58m2 stops

$222United Airlines

Find Deal

Thu, Oct 16 - Sat, Oct 18

12:47 pm - 7:59 pmONT-DRO

6h 12m1 stop

6:09 am - 11:56 amDRO-ONT

6h 47m1 stop

$258American Airlines

Find Deal

Tue, Sep 30 - Sat, Oct 4

9:50 am - 5:09 pmONT-COS

6h 19m1 stop

8:09 am - 5:10 pmCOS-ONT

10h 01m2 stops

$260Delta

Find Deal

Sat, Oct 18 - Sat, Oct 25

1:15 pm - 6:26 pmONT-ASE

4h 11m1 stop

2:00 pm - 8:24 pmASE-ONT

7h 24m1 stop

$269United Airlines

Find Deal

Tue, Sep 30 - Sat, Oct 4

6:10 am - 11:16 amONT-GJT

4h 06m1 stop

6:02 am - 11:56 amGJT-ONT

6h 54m1 stop

$269American Airlines

Find Deal

Tue, Sep 30 - Sat, Oct 4

Frontier flights from Ontario to Colorado

Our best Frontier deals on Ontario to Colorado flight tickets

Frontier

Dec 5

ONT11:52 amOntario

2h 22m

DEN3:14 pmDenver Intl

Dec 15

DEN9:30 amDenver Intl

2h 27m

ONT10:57 amOntario

$67

Find similar

Frontier

Oct 14

ONT7:04 amOntario

2h 27m

DEN10:31 amDenver Intl

Oct 18

DEN10:29 pmDenver Intl

2h 21m

ONT11:50 pmOntario

$68

Find similar

Frontier

Oct 14

ONT7:04 amOntario

2h 27m

DEN10:31 amDenver Intl

Oct 17

DEN8:15 amDenver Intl

2h 20m

ONT9:35 amOntario

$71

Find similar

United Airlines flights from Ontario to Colorado

Our best United Airlines deals on Ontario to Colorado flight tickets

United Airlines

Oct 16

ONT6:27 pmOntario

4h 25m

1 stop

COS11:52 pmColorado Springs

Oct 18

COS1:54 pmColorado Springs

9h 58m

2 stops

ONT10:52 pmOntario

$222

Find similar

United Airlines

Sep 30

ONT1:15 pmOntario

4h 11m

1 stop

ASE6:26 pmAspen Pitkin County

Oct 4

ASE2:00 pmAspen Pitkin County

7h 24m

1 stop

ONT8:24 pmOntario

$269

Find similar

United Airlines

Oct 11

ONT1:53 pmOntario

7h 01m

2 stops

COS9:54 pmColorado Springs

Oct 14

COS5:10 pmColorado Springs

4h 14m

1 stop

ONT8:24 pmOntario

$274

Find similar

Fly from

Fly to

Route

Depart

Return

Price

OntarioDenver

ONT - DEN

ONTDEN

Ontario

Fri 12/5

11:52 am-3:14 pm

Nonstop2h 22m

Denver Intl

Mon 12/15

9:30 am-10:57 am

Nonstop2h 27m

$67

OntarioDenver

ONT - DEN

ONTDEN

Ontario

Tue 10/14

7:04 am-10:31 am

Nonstop2h 27m

Denver Intl

Sat 10/18

10:29 pm-11:50 pm

Nonstop2h 21m

$68

OntarioColorado Springs

ONT - COS

ONTCOS

Ontario

Mon 10/13

5:55 pm-12:35 am

1 stop5h 40m

Colorado Springs

Mon 10/20

6:15 pm-11:40 pm

1 stop6h 25m

$177

OntarioColorado Springs

ONT - COS

ONTCOS

Ontario

Wed 10/22

2:20 pm-9:10 pm

1 stop5h 50m

Colorado Springs

Sat 10/25

6:00 am-12:45 pm

2 stops7h 45m

$182

OntarioColorado Springs

ONT - COS

ONTCOS

Ontario

Sat 10/11

9:50 am-5:09 pm

1 stop6h 19m

Colorado Springs

Tue 10/14

5:49 pm-11:39 pm

1 stop6h 50m

$217

OntarioColorado Springs

ONT - COS

ONTCOS

Ontario

Thu 10/16

6:27 pm-11:52 pm

1 stop4h 25m

Colorado Springs

Sat 10/18

1:54 pm-10:52 pm

2 stops9h 58m

$222

OntarioDurango

ONT - DRO

ONTDRO

Ontario

Tue 9/30

12:47 pm-7:59 pm

1 stop6h 12m

Durango La Plata County

Sat 10/4

6:09 am-11:56 am

1 stop6h 47m

$258

OntarioColorado Springs

ONT - COS

ONTCOS

Ontario

Sat 10/18

9:50 am-5:09 pm

1 stop6h 19m

Colorado Springs

Sat 10/25

8:09 am-5:10 pm

2 stops10h 01m

$260

OntarioAspen

ONT - ASE

ONTASE

Ontario

Tue 9/30

1:15 pm-6:26 pm

1 stop4h 11m

Aspen Pitkin County

Sat 10/4

2:00 pm-8:24 pm

1 stop7h 24m

$269

OntarioGrand Junction

ONT - GJT

ONTGJT

Ontario

Tue 9/30

6:10 am-11:16 am

1 stop4h 06m

Grand Junction Regnl

Sat 10/4

6:02 am-11:56 am

1 stop6h 54m

$269

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How to get the cheapest flight ticket from Ontario to Colorado

Look no further. We've gone through all the searches for this route on momondo so you have the important information and insights to find the cheapest flight ticket for your trip

Prices

Airlines

Other information

What is the cheapest month to fly to Colorado?

The month of January is, on average, the cheapest month to fly to Colorado from Ontario, with most prices found around $99. The month of February is another great option to travel to Colorado, with average flight prices from Ontario averaging around $108.

What is the cheapest day to depart on your flight to Colorado?

The cheapest day to depart from Ontario to Colorado is on a Friday when prices can be found for as low as $249. On the other hand, Sunday is the most expensive day to depart from Ontario because it is more convenient for both business and leisure travelers. As a result, prices tend to be around $326.

What is the cheapest time of day to depart on your flight to Colorado?

The cheapest time of day to fly to Colorado is in the evening when flights can be purchased for as low as $195. At noon is when there is more demand to fly to Colorado, so prices are often more expensive at around $437 per ticket.

What is the cheapest Ontario to Colorado flight route?

Fly from Ontario to Denver Intl for the best Ontario - Colorado flight prices

How far in advance should I book a flight to Colorado?

You are more likely to see cheaper flights to Colorado from Ontario when booking weeks ahead of your departure date. In general, you can expect to find flights to Colorado for around $152 when searching weeks out. However, flight prices might be lower outside of this timeframe. For example, people recently found flights to Colorado from Ontario for as low as $127 on momondo.

What cabin class options are available on Ontario to Colorado flights?

There are 4 cabin classes available to choose from on Ontario to Colorado flights. Cabin price and availability will vary by airline so perform a search above to find the right deals for you.

Can stopping save me money on Ontario to Colorado flights?

No. A direct flight is the cheapest option for a flight between Ontario to Colorado.

Cheap Ontario to Colorado flight deals and tips

Find info about flight duration, direct flights, and airports for your flight from Ontario to Colorado

Best Price Found	$121
Fastest flight time	2h 10m
Direct flights	Every day
Airports in Colorado	1 airport

The best one-way flight to Colorado from Ontario in the past 72 hours is $121. The best round-trip flight deal from Ontario to Colorado found on momondo in the last 72 hours is $168.

The fastest flight from Ontario to Colorado takes 2h 10m

Direct flights go from Ontario to Colorado every day.

There is 1 airport near Colorado: Denver Intl (DEN)

Search flight deals

When did momondo last update prices for flights from Ontario Airport to Colorado?
Prices for flights from Ontario Airport to Colorado refresh daily.
How many operators does momondo search for flights from Ontario Airport to Colorado?
As of September 2025, there are 5 operators available to choose from for flights from Ontario Airport to Colorado.
How old do you have to be to fly from Ontario Airport to Colorado?
The minimum age for a child to fly alone is five, but airlines offering an unaccompanied minor (UNMR) service may have their age restrictions, such as regulations concerning flight duration, timing, and layovers. It is recommended that you verify with the airline you are booking with for travel from Ontario Airport to Colorado.
What documentation or ID do you need to fly to Colorado?
The travel and health documents required for your trip to Colorado can vary based on your itinerary and personal situation. As a rule, consider having multiple documents such as a national ID card or driver’s license, and a passport valid for six-months after you plan to arrive at Colorado. We always recommend checking with your airline or a trusted third party such as IATA to get advice.
What is the most popular plane model from Ontario to Colorado?
Based on momondo bookings for flights between Ontario and Colorado, the leading plane model is Airbus A321neo, making up 13.06% of the total bookings. Other popular models include Airbus A320neo with 12.93%, Boeing 737 MAX 8 with 12.10%, and Boeing 737-800 with 10.27%.

Best airlines flying from Ontario to Colorado

Compare and see reviews for airlines that fly from Ontario to Colorado with momondo

Airline	Rating	Free Cancellation	Price
Frontier	PriceFrom $58	Free Cancellation	Rating 5.8 3,174 reviews	Search Frontier flights
Delta	PriceFrom $109	Free Cancellation	Rating 7.9 7,957 reviews	Search Delta flights
Southwest	PriceFrom $121	Free Cancellation	Rating 8.0 4,242 reviews	Search Southwest flights
United Airlines	PriceFrom $136	Free Cancellation	Rating 7.4 8,924 reviews	Search United Airlines flights
American Airlines	PriceFrom $268	Free Cancellation	Rating 7.2 10,000 reviews	Search American Airlines flights

Why use momondo?

Why should I use momondo to find a flight deal from Ontario to Colorado?

We help find the flight that best suits your needs, momondo compares prices from hundreds of airlines and travel agents and helps you filter them to find the best flight from Ontario to Colorado for you.

Can I find flights from Ontario to Colorado with flexible booking policies on momondo?

All flight searches from Ontario to Colorado on momondo can be filtered to show those which offer flexible booking policies.

How can momondo help me find flights from Ontario to Colorado?

momondo offers useful filters to help you find the right flight. Choose specific flight times, airports or even what payment method you prefer. We have numerous options to help you book your ideal flight from Ontario to Colorado.

I’m not ready to book a flight from Ontario to Colorado right now. Can momondo alert me if prices change?

Yes. momondo can track prices for Ontario to Colorado flights and alert you when they change. Perform a search to set up the price alert. All that is required is a valid email address.

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Popular cities in Colorado

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Cheap flights from Ontario to Colorado from $51

This is the cheapest one-way flight price found by a momondo user in the last 72 hours by searching for a flight from Ontario to Colorado departing on 9/26. Fares may change, and may not be available for all flights or travel dates. Click the price to refresh the search for this deal.

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Filter for what you want

Filter for what you want

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Find the cheapest flights from Ontario to Colorado

Cheap round-trip flights

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Cheap direct flights

Frontier flights from Ontario to Colorado

Our best Frontier deals on Ontario to Colorado flight tickets

United Airlines flights from Ontario to Colorado

Our best United Airlines deals on Ontario to Colorado flight tickets

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Use the filters below to find and compare flights from Ontario to Colorado that are best for you.

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How to get the cheapest flight ticket from Ontario to Colorado

Look no further. We've gone through all the searches for this route on momondo so you have the important information and insights to find the cheapest flight ticket for your trip

What is the cheapest month to fly to Colorado?

The month of January is, on average, the cheapest month to fly to Colorado from Ontario, with most prices found around $99. The month of February is another great option to travel to Colorado, with average flight prices from Ontario averaging around $108.

What is the cheapest day to depart on your flight to Colorado?

What is the cheapest time of day to depart on your flight to Colorado?

The cheapest time of day to fly to Colorado is in the evening when flights can be purchased for as low as $195. At noon is when there is more demand to fly to Colorado, so prices are often more expensive at around $437 per ticket.

What is the cheapest Ontario to Colorado flight route?

Fly from Ontario to Denver Intl for the best Ontario - Colorado flight prices

How far in advance should I book a flight to Colorado?

What cabin class options are available on Ontario to Colorado flights?

There are 4 cabin classes available to choose from on Ontario to Colorado flights. Cabin price and availability will vary by airline so perform a search above to find the right deals for you.

Can stopping save me money on Ontario to Colorado flights?

No. A direct flight is the cheapest option for a flight between Ontario to Colorado.

What is the cheapest airline that flies from Ontario to Colorado?

Frontier, Southwest, and American Airlines are the most popular carriers operating from Ontario to Colorado

What airlines fly to Colorado?

How many flights depart from Ontario to Colorado on average per day?

The number of flights available between Ontario and Colorado is 8 per day as of September 2025. The most frequent departure time is 5:00AM, with 36% of daily flights leaving in the afternoon.

How many flights depart from Ontario to Colorado on average per week?

60 flights are operational weekly from Ontario to Colorado as of September 2025. The most popular departure day for this route is Mon, with 18% of flights per week taking off on this day.

Cheap Ontario to Colorado flight deals and tips

Find info about flight duration, direct flights, and airports for your flight from Ontario to Colorado

Best Price Found

Fastest flight time

Direct flights

Airports in Colorado

When did momondo last update prices for flights from Ontario Airport to Colorado?

How many operators does momondo search for flights from Ontario Airport to Colorado?

How old do you have to be to fly from Ontario Airport to Colorado?

What documentation or ID do you need to fly to Colorado?

What is the most popular plane model from Ontario to Colorado?

Best airlines flying from Ontario to Colorado

Compare and see reviews for airlines that fly from Ontario to Colorado with momondo

Why use momondo?

Why should I use momondo to find a flight deal from Ontario to Colorado?

Can I find flights from Ontario to Colorado with flexible booking policies on momondo?

How can momondo help me find flights from Ontario to Colorado?

I’m not ready to book a flight from Ontario to Colorado right now. Can momondo alert me if prices change?

An easier way to manage your Colorado trip

We make it super easy to schedule, organize and travel with friends or family. Trips is free — and available to use no matter where you book.

Get notified when prices go down

Daily price changes in your inbox - only with Price Alerts.

Find better results for your trip to Colorado

Popular cities in Colorado

Popular flights according to clicks in the last 7 days on momondo