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

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

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

55 flights are operational weekly from Ontario to Colorado as of March 2026. 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 7 per day as of March 2026. The most frequent departure time is 5:00AM, with 35% of daily flights leaving at noon.

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 46% of people opting to fly with this airline when traveling to Colorado. Keep in mind that there are 9 different airlines that fly to Colorado on a routine basis, so you have a few additional options to choose from.

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 March 2026, 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.

$79 Cheap Flights from Ontario to Colorado in 2026

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Find the cheapest flights from Ontario to Colorado

Round-trip

One-way

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Cheap round-trip flights

Enter your travel dates to find the best prices.

12:59 am - 4:15 am

ONT

DEN

2h 16mnonstop

10:29 pm - 11:55 pm

DEN

ONT

2h 26mnonstop

$87Frontier

Mon, Apr 13 - Tue, Apr 14

12:59 am - 4:15 am

ONT

DEN

2h 16mnonstop

10:29 pm - 11:55 pm

DEN

ONT

2h 26mnonstop

$88Frontier

Mon, Apr 20 - Sat, Apr 25

5:10 am - 11:05 am

ONT

COS

4h 55m

1 stop

5:13 pm - 8:36 pm

COS

ONT

4h 23m

1 stop

$217United Airlines

Tue, Apr 14 - Tue, Apr 14

6:30 am - 3:30 pm

ONT

COS

8h 00m

2 stops

4:45 pm - 9:30 pm

COS

ONT

5h 45m

1 stop

$222Southwest

Tue, Apr 14 - Tue, Apr 14

6:30 am - 3:30 pm

ONT

COS

8h 00m

2 stops

4:45 pm - 10:10 pm

COS

ONT

6h 25m

2 stops

$227Southwest

Tue, Apr 14 - Tue, Apr 14

6:00 am - 11:24 am

ONT

COS

4h 24m

1 stop

7:59 am - 12:14 pm

COS

ONT

5h 15m

1 stop

$237Delta

Sat, Apr 11 - Sat, Apr 25

5:10 am - 11:05 am

ONT

COS

4h 55m

1 stop

3:26 pm - 10:45 pm

COS

ONT

8h 19m

2 stops

$242United Airlines

Sat, Apr 11 - Sat, Apr 25

12:22 pm - 6:21 pm

ONT

GJT

4h 59m

1 stop

11:46 am - 4:22 pm

GJT

ONT

5h 36m

1 stop

$271American Airlines

Fri, Apr 3 - Tue, Apr 7

1:00 pm - 6:10 pm

ONT

GJT

4h 10m

1 stop

6:56 pm - 11:44 pm

GJT

ONT

5h 48m

1 stop

$280Delta

Thu, Aug 27 - Mon, Aug 31

6:15 am - 11:04 am

ONT

DRO

3h 49m

1 stop

5:04 pm - 11:46 pm

DRO

ONT

7h 42m

1 stop

$284American Airlines

Sat, Apr 4 - Wed, Apr 8

Frontier flights from Ontario to Colorado

Our best Frontier deals on Ontario to Colorado flight tickets

Frontier

Apr 13

ONT12:59 amOntario

2h 16m

DEN4:15 amDenver Intl

Apr 14

DEN10:29 pmDenver Intl

2h 26m

ONT11:55 pmOntario

$87

Frontier

Apr 20

ONT12:59 amOntario

2h 16m

DEN4:15 amDenver Intl

Apr 28

DEN10:29 pmDenver Intl

2h 26m

ONT11:55 pmOntario

$88

Frontier

May 20

ONT10:50 amOntario

2h 22m

DEN2:12 pmDenver Intl

May 26

DEN8:41 amDenver Intl

2h 24m

ONT10:05 amOntario

$89

Delta flights from Ontario to Colorado

Our best Delta deals on Ontario to Colorado flight tickets

Delta

Apr 11

ONT6:00 amOntario

4h 24m

1 stop

COS11:24 amColorado Springs

Apr 25

COS7:59 amColorado Springs

5h 15m

1 stop

ONT12:14 pmOntario

$237

Delta

Aug 27

ONT1:00 pmOntario

4h 10m

1 stop

GJT6:10 pmGrand Junction Regnl

Aug 31

GJT6:56 pmGrand Junction Regnl

5h 48m

1 stop

ONT11:44 pmOntario

$280

Delta

Apr 9

ONT5:09 pmOntario

3h 56m

1 stop

COS10:05 pmColorado Springs

Apr 15

COS11:55 amColorado Springs

5h 30m

1 stop

ONT4:25 pmOntario

$338

Fly from

Fly to

Route

Depart

Return

Price

Cheapest round-trip

Quickest round-trip

OntarioDenver

ONT - DEN

ONTDEN

Ontario

Mon 4/13

12:59 am-4:15 am

Nonstop2h 16m

Denver Intl

Tue 4/14

10:29 pm-11:55 pm

Nonstop2h 26m

$87

OntarioDenver

ONT - DEN

ONTDEN

Ontario

Mon 4/20

12:59 am-4:15 am

Nonstop2h 16m

Denver Intl

Sat 4/25

10:29 pm-11:55 pm

Nonstop2h 26m

$88

OntarioColorado Springs

ONT - COS

ONTCOS

Ontario

Tue 4/14

5:10 am-11:05 am

1 stop4h 55m

Colorado Springs

Tue 4/14

5:13 pm-8:36 pm

1 stop4h 23m

$217

OntarioColorado Springs

ONT - COS

ONTCOS

Ontario

Tue 4/14

6:30 am-3:30 pm

2 stops8h 00m

Colorado Springs

Tue 4/14

4:45 pm-9:30 pm

1 stop5h 45m

$222

OntarioColorado Springs

ONT - COS

ONTCOS

Ontario

Tue 4/14

6:30 am-3:30 pm

2 stops8h 00m

Colorado Springs

Tue 4/14

4:45 pm-10:10 pm

2 stops6h 25m

$227

OntarioColorado Springs

ONT - COS

ONTCOS

Ontario

Sat 4/11

6:00 am-11:24 am

1 stop4h 24m

Colorado Springs

Sat 4/25

7:59 am-12:14 pm

1 stop5h 15m

$237

OntarioColorado Springs

ONT - COS

ONTCOS

Ontario

Sat 4/11

5:10 am-11:05 am

1 stop4h 55m

Colorado Springs

Sat 4/25

3:26 pm-10:45 pm

2 stops8h 19m

$242

OntarioGrand Junction

ONT - GJT

ONTGJT

Ontario

Fri 4/3

12:22 pm-6:21 pm

1 stop4h 59m

Grand Junction Regnl

Tue 4/7

11:46 am-4:22 pm

1 stop5h 36m

$271

OntarioGrand Junction

ONT - GJT

ONTGJT

Ontario

Thu 8/27

1:00 pm-6:10 pm

1 stop4h 10m

Grand Junction Regnl

Mon 8/31

6:56 pm-11:44 pm

1 stop5h 48m

$280

OntarioDurango

ONT - DRO

ONTDRO

Ontario

Sat 4/4

6:15 am-11:04 am

1 stop3h 49m

Durango La Plata County

Wed 4/8

5:04 pm-11:46 pm

1 stop7h 42m

$284

Flights are sorted by cheapest round-trip flights first.

Showing 1-10 of 20 resultsSorted by cheapest first

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 September is, on average, the cheapest month to fly to Colorado from Ontario, with most prices found around $165. The month of February is another great option to travel to Colorado, with average flight prices from Ontario averaging around $167.

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 $260. On the other hand, Monday 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 $316.

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 $210. At noon is when there is more demand to fly to Colorado, so prices are often more expensive at around $427 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 $188 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 $143 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	$167
Fastest flight time	2h 12m
Direct flights	Every day
Airports in Colorado	87 airports

The best one-way flight to Colorado from Ontario in the past 72 hours is $167. The best round-trip flight deal from Ontario to Colorado found on momondo in the last 72 hours is $255.

The fastest flight from Ontario to Colorado takes 2h 12m

Direct flights go from Ontario to Colorado every day.

There are 87 airports in Colorado. From Ontario there are direct flights to 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 March 2026, 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 Boeing 737 MAX 8, making up 13.18% of the total bookings. Other popular models include Airbus A321neo with 11.77%, Boeing 737-800 with 10.76%, and Airbus A320neo with 10.28%.

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 $62	Free Cancellation	Rating 5.7 3,023 reviews	Search Frontier flights
Delta	PriceFrom $109	Free Cancellation	Rating 7.9 8,313 reviews	Search Delta flights
United Airlines	PriceFrom $135	Free Cancellation	Rating 7.4 9,451 reviews	Search United Airlines flights
Southwest	PriceFrom $144	Free Cancellation	Rating 8.0 4,325 reviews	Search Southwest flights
American Airlines	PriceFrom $211	Free Cancellation	Rating 7.1 11,488 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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Flights to Las Vegasfrom $57

Flights to Washington, D.C.from $59

Flights to Bostonfrom $70

Flights to Atlantafrom $49

Flights to Dallasfrom $60

Flights to Seattlefrom $71

Cheap flights from Ontario to Colorado from $79

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 4/19. 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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Our best Frontier deals on Ontario to Colorado flight tickets

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Our best Delta deals on Ontario to Colorado flight tickets

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See travel insights to Colorado from

How to get the cheapest flight ticket from Ontario to Colorado

What is the cheapest month to fly to Colorado?

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?

What is the cheapest Ontario to Colorado flight route?

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

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

Can stopping save me money on Ontario to Colorado flights?

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

What airlines fly to Colorado?

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

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

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

Best airlines flying from Ontario to Colorado

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

Why use momondo?

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.

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