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

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

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

15 flights are operational daily from California to Ontario as of August 2025. The most popular departure time for this route is 10:00AM, with 36% of flights per day taking off in the afternoon.

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

As of August 2025, there are 109 flights per week flying from California to Ontario. The most common day of the week flights depart is Thu, with 29% of flights taking off on this day.

What airlines fly to Ontario?

Frontier, Southwest and United Airlines are the top three most popular airlines that fly to Ontario from California according to our data. Frontier is the first choice among our users, with 40% of people opting to fly with this airline when traveling to Ontario. Keep in mind that there are 10 different airlines that fly to Ontario on a routine basis, so you have a few additional options to choose from.

How long does it take to fly to Ontario?

Average flight duration from California to Ontario depends on which airport you fly into and out of. Flying from San Diego to Los Angeles is 1h 04m on average, while flying from San Jose to Los Angeles is 1h 19m on average. Los Angeles is the most popular airport in Ontario.

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

Prices for flights from California to Ontario Airport refresh daily.

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

As of August 2025, there are 8 operators available to choose from for flights from California to Ontario Airport.

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

Although the minimum age for a child to fly alone is five, airlines that offer an unaccompanied minor (UMNR) service may have their own age limits, which could be impacted by factors such as flight length, timing, and layovers. It is recommended that you verify with the airline you are booking with for travel from California to Ontario Airport.

What documentation or ID do you need to fly to Ontario Airport?

The travel and health documents required for your trip to Ontario Airport 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 Ontario Airport. We always recommend checking with your airline or a trusted third party such as IATA to get advice.

$29 Cheap Flights from California to Ontario in 2025

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Find the cheapest flights from California to Los Angeles

Round-trip

One-way

Last minute

Direct

Cheap round-trip flights

10:21 am - 11:31 amLAS-ONT

1h 10mnonstop

6:00 am - 7:13 amONT-LAS

1h 13mnonstop

$58Frontier

Find Deal

Thu, Aug 21 - Sun, Aug 24

3:42 pm - 4:53 pmLAS-ONT

1h 11mnonstop

8:00 am - 9:13 amONT-LAS

1h 13mnonstop

$59Frontier

Find Deal

Thu, Aug 21 - Wed, Aug 27

6:05 am - 7:30 amOAK-ONT

1h 25mnonstop

5:50 am - 7:10 amONT-OAK

1h 20mnonstop

$97Southwest

Find Deal

Thu, Aug 28 - Mon, Sep 1

9:55 am - 11:05 amLAS-ONT

1h 10mnonstop

5:05 pm - 6:15 pmONT-LAS

1h 10mnonstop

$97Southwest

Find Deal

Thu, Aug 21 - Mon, Aug 25

7:10 pm - 8:33 pmSFO-ONT

1h 23mnonstop

6:50 pm - 8:09 pmONT-SFO

1h 19mnonstop

$97United Airlines

Find Deal

Thu, Sep 11 - Mon, Sep 15

10:45 am - 12:13 pmSFO-ONT

1h 28mnonstop

1:42 pm - 3:01 pmONT-SFO

1h 19mnonstop

$124United Airlines

Find Deal

Thu, Aug 21 - Sun, Aug 24

12:59 pm - 5:50 pmSTS-ONT

4h 51m1 stop

9:00 am - 3:47 pmONT-STS

6h 47m1 stop

$198American Airlines

Find Deal

Sat, Aug 30 - Sun, Aug 31

12:59 pm - 5:50 pmSTS-ONT

4h 51m1 stop

9:00 am - 3:47 pmONT-STS

6h 47m1 stop

$199American Airlines

Find Deal

Sat, Aug 30 - Sun, Aug 31

5:14 am - 9:26 amMFR-ONT

4h 12m1 stop

11:39 am - 5:06 pmONT-MFR

5h 27m1 stop

$237Alaska Airlines

Find Deal

Mon, Sep 15 - Mon, Sep 15

5:14 am - 9:26 amMFR-ONT

4h 12m1 stop

7:47 pm - 11:59 amONT-MFR

16h 12m2 stops

$298Alaska Airlines

Find Deal

Mon, Sep 15 - Mon, Sep 15

Frontier flights from California to Ontario

Our best Frontier deals on California to Ontario flight tickets

Frontier

Aug 21

LAS10:21 amLas Vegas Harry Reid Intl

1h 10m

ONT11:31 amOntario

Aug 24

ONT6:00 amOntario

1h 13m

LAS7:13 amLas Vegas Harry Reid Intl

$58

Find similar

Frontier

Aug 21

LAS3:42 pmLas Vegas Harry Reid Intl

1h 11m

ONT4:53 pmOntario

Aug 27

ONT8:00 amOntario

1h 13m

LAS9:13 amLas Vegas Harry Reid Intl

$59

Find similar

Frontier

Aug 19

LAS3:07 pmLas Vegas Harry Reid Intl

1h 11m

ONT4:18 pmOntario

Aug 23

ONT8:00 amOntario

1h 13m

LAS9:13 amLas Vegas Harry Reid Intl

$72

Find similar

American Airlines flights from California to Ontario

Our best American Airlines deals on California to Ontario flight tickets

American Airlines

Aug 30

STS12:59 pmSanta Rosa Sonoma County

4h 51m

1 stop

ONT5:50 pmOntario

Aug 31

ONT9:00 amOntario

6h 47m

1 stop

STS3:47 pmSanta Rosa Sonoma County

$198

Find similar

American Airlines

Aug 30

STS12:59 pmSanta Rosa Sonoma County

4h 51m

1 stop

ONT5:50 pmOntario

Aug 31

ONT9:00 amOntario

6h 47m

1 stop

STS3:47 pmSanta Rosa Sonoma County

$199

Find similar

American Airlines

Sep 30

RNO12:53 pmReno

5h 23m

1 stop

ONT6:16 pmOntario

Oct 5

ONT6:10 amOntario

5h 53m

1 stop

RNO12:03 pmReno

$219

Find similar

Fly from

Fly to

Route

Depart

Return

Price

Las VegasOntario

LAS - ONT

LASONT

Las Vegas Harry Reid Intl

Thu 8/21

10:21 am-11:31 am

Nonstop1h 10m

Ontario

Sun 8/24

6:00 am-7:13 am

Nonstop1h 13m

$58

Las VegasOntario

LAS - ONT

LASONT

Las Vegas Harry Reid Intl

Thu 8/21

3:42 pm-4:53 pm

Nonstop1h 11m

Ontario

Wed 8/27

8:00 am-9:13 am

Nonstop1h 13m

$59

OaklandOntario

OAK - ONT

OAKONT

Oakland

Thu 8/28

6:05 am-7:30 am

Nonstop1h 25m

Ontario

Mon 9/1

5:50 am-7:10 am

Nonstop1h 20m

$97

Las VegasOntario

LAS - ONT

LASONT

Las Vegas Harry Reid Intl

Thu 8/21

9:55 am-11:05 am

Nonstop1h 10m

Ontario

Mon 8/25

5:05 pm-6:15 pm

Nonstop1h 10m

$97

San FranciscoOntario

SFO - ONT

SFOONT

San Francisco

Thu 9/11

7:10 pm-8:33 pm

Nonstop1h 23m

Ontario

Mon 9/15

6:50 pm-8:09 pm

Nonstop1h 19m

$97

San FranciscoOntario

SFO - ONT

SFOONT

San Francisco

Thu 8/21

10:45 am-12:13 pm

Nonstop1h 28m

Ontario

Sun 8/24

1:42 pm-3:01 pm

Nonstop1h 19m

$124

Santa RosaOntario

STS - ONT

STSONT

Santa Rosa Sonoma County

Sat 8/30

12:59 pm-5:50 pm

1 stop4h 51m

Ontario

Sun 8/31

9:00 am-3:47 pm

1 stop6h 47m

$198

Santa RosaOntario

STS - ONT

STSONT

Santa Rosa Sonoma County

Sat 8/30

12:59 pm-5:50 pm

1 stop4h 51m

Ontario

Sun 8/31

9:00 am-3:47 pm

1 stop6h 47m

$199

MedfordOntario

MFR - ONT

MFRONT

Medford

Mon 9/15

5:14 am-9:26 am

1 stop4h 12m

Ontario

Mon 9/15

11:39 am-5:06 pm

1 stop5h 27m

$237

MedfordOntario

MFR - ONT

MFRONT

Medford

Mon 9/15

5:14 am-9:26 am

1 stop4h 12m

Ontario

Mon 9/15

7:47 pm-11:59 am

2 stops16h 12m

$298

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How to get the cheapest flight ticket from California to Ontario

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 California to Ontario flight route?

Fly from San Francisco to Ontario for the best California - Ontario flight prices

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

There are 4 cabin classes available to choose from on California to Ontario 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 California to Ontario flights?

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

Cheap California to Ontario flight deals and tips

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

Best Price Found	$29
Fastest flight time	1h 03m
Direct flights	Every day
Airports in Ontario	1 airport

The best one-way flight to Ontario from California in the past 72 hours is $29. The best round-trip flight deal from California to Ontario found on momondo in the last 72 hours is $58.

The fastest flight from California to Ontario takes 1h 03m

Direct flights go from California to Ontario every day.

There is 1 airport near Ontario: Ontario (ONT)

Search flight deals

When did momondo last update prices for flights from California to Ontario Airport?
Prices for flights from California to Ontario Airport refresh daily.
How many operators does momondo search for flights from California to Ontario Airport?
As of August 2025, there are 8 operators available to choose from for flights from California to Ontario Airport.
How old do you have to be to fly from California to Ontario Airport?
Although the minimum age for a child to fly alone is five, airlines that offer an unaccompanied minor (UMNR) service may have their own age limits, which could be impacted by factors such as flight length, timing, and layovers. It is recommended that you verify with the airline you are booking with for travel from California to Ontario Airport.
What documentation or ID do you need to fly to Ontario Airport?
The travel and health documents required for your trip to Ontario Airport 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 Ontario Airport. 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 California to Ontario?
momondo data reveals that the most frequently booked plane model on the route from California to Ontario is Boeing 737-800, representing 13.70% of all bookings. The subsequent popular models are Airbus A320neo at 12.51%, Airbus A320-100/200 at 12.07%, and Airbus A321neo at 10.27%.

Best airlines flying from California to Ontario

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

Airline	Rating	Free Cancellation	Price
Spirit Airlines	PriceFrom $24	Free Cancellation	Rating 6.3 8,049 reviews	Search Spirit Airlines flights
Frontier	PriceFrom $27	Free Cancellation	Rating 5.9 3,239 reviews	Search Frontier flights
United Airlines	PriceFrom $58	Free Cancellation	Rating 7.4 8,900 reviews	Search United Airlines flights
Delta	PriceFrom $58	Free Cancellation	Rating 8.0 7,981 reviews	Search Delta flights
Alaska Airlines	PriceFrom $59	Free Cancellation	Rating 8.0 10,000 reviews	Search Alaska Airlines flights
Southwest	PriceFrom $145	Free Cancellation	Rating 8.0 4,246 reviews	Search Southwest flights
American Airlines	PriceFrom $186	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 California to Ontario?

To find the flight that best suits your needs, momondo gathers a range of flights from a large pool of different airlines and agents; you can then use our insights and filters to find and book the right flight to Ontario from California.

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

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

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

Once you have performed a search for California to Ontario flights, momondo helps you find the right one by offering useful filters to narrow down your flight selection. Flights can be filtered by multiple factors such as airline, airport and price; but also by other criteria like aircraft type and payment method.

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

Yes momondo offers price alerts on flights to Ontario from California. After performing a search on this page you should be able to see the price alert set up feature. Simply provide a valid email address and momondo will instantly alert you when prices change.

An easier way to manage your Ontario 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.

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Find better results for your trip to the United States

Airports servicing California

Popular cities in the United States

Flights to New Yorkfrom $39

Flights to Los Angelesfrom $37

Flights to Miamifrom $58

Flights to Chicagofrom $59

Flights to Orlandofrom $54

Flights to Las Vegasfrom $35

Flights to San Franciscofrom $49

Flights to Washington, D.C.from $49

Flights to Bostonfrom $77

Flights to Atlantafrom $29

Flights to Dallasfrom $55

Flights to Seattlefrom $93

Fly to other destinations from California

Flights from Oakland to Missoula Johnson-Bell Field

Flights from San Francisco to Ontario

Flights from San Francisco to San Diego

Flights from Santa Ana J. Wayne/Orange Cnty to Las Vegas Harry Reid Intl

Flights from Santa Ana J. Wayne/Orange Cnty to Colorado Springs

Flights from Santa Ana J. Wayne/Orange Cnty to Medford

Cheap flights from California to Los Angeles from $29

This is the cheapest one-way flight price found by a momondo user in the last 72 hours by searching for a flight from California to Los Angeles departing on 8/11. Fares may change, and may not be available for all flights or travel dates. Click the price to refresh the search for this deal.

Big names and deals

Big names and deals

Filter for what you want

Filter for what you want

Trusted and free

Trusted and free

Price Alerts

Price Alerts

Find the cheapest flights from California to Los Angeles

Cheap round-trip flights

Cheap one-way flights

Cheap last minute flights

Cheap direct flights

Frontier flights from California to Ontario

Our best Frontier deals on California to Ontario flight tickets

American Airlines flights from California to Ontario

Our best American Airlines deals on California to Ontario flight tickets

momondo Fare Finder

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

See travel insights to Los Angeles from

How to get the cheapest flight ticket from California to Ontario

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 California to Ontario flight route?

Fly from San Francisco to Ontario for the best California - Ontario flight prices

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

There are 4 cabin classes available to choose from on California to Ontario 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 California to Ontario flights?

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

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

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

What airlines fly to Ontario?

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

15 flights are operational daily from California to Ontario as of August 2025. The most popular departure time for this route is 10:00AM, with 36% of flights per day taking off in the afternoon.

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

As of August 2025, there are 109 flights per week flying from California to Ontario. The most common day of the week flights depart is Thu, with 29% of flights taking off on this day.

How long does it take to fly to Ontario?

Average flight duration from California to Ontario depends on which airport you fly into and out of. Flying from San Diego to Los Angeles is 1h 04m on average, while flying from San Jose to Los Angeles is 1h 19m on average. Los Angeles is the most popular airport in Ontario.

Cheap California to Ontario flight deals and tips

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

Best Price Found

Fastest flight time

Direct flights

Airports in Ontario

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

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

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

What documentation or ID do you need to fly to Ontario Airport?

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

Best airlines flying from California to Ontario

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

Why use momondo?

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

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

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

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

An easier way to manage your Ontario 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 the United States

Airports servicing California