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Ontario

$30+ Cheap flights from California to Ontario (ONT)

This is the cheapest one-way flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 2/5. Fares are subject to change and may not be available on all flights or dates of travel.
LAX — ONT
Jan 20 — Jan 271
Tue 1/20
Tue 1/27
1 adult, Economy
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Cheap flight deals from California to Ontario

Cheapest flights from California to Ontario
Explore the most affordable flight options available from California to Ontario. Find the lowest fares from popular airlines and budget airlines, with prices last updated on December 21, 2025.

This CheapOair deal was found by Cheapflights users on 12/18. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 12/284:33 pmLAS - ONT
Nonstop1h 09mFrontier
Wed 1/710:45 amONT - LAS
Nonstop1h 09mFrontier
Deal found 12/18$79
This Trip.com deal was found by Cheapflights users on 12/17. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 12/284:33 pmLAS - ONT
Nonstop1h 09mFrontier
Sun 1/46:37 pmONT - LAS
Nonstop1h 11mFrontier
Deal found 12/17$96
This Super.com deal was found by Cheapflights users on 12/20. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 12/2710:18 pmLAS - ONT
Nonstop1h 03mFrontier
Sun 12/286:00 amONT - LAS
Nonstop1h 07mFrontier
Deal found 12/20$97
This Super.com deal was found by Cheapflights users on 12/19. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 12/264:01 pmLAS - ONT
Nonstop1h 08mFrontier
Sat 12/275:16 pmONT - LAS
Nonstop1h 09mFrontier
Deal found 12/19$106
This Super.com deal was found by Cheapflights users on 12/18. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 12/254:13 pmLAS - ONT
Nonstop1h 09mFrontier
Sat 12/276:00 amONT - LAS
Nonstop1h 07mFrontier
Deal found 12/18$107
This Frontier deal was found by Cheapflights users on 12/17. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 12/254:13 pmLAS - ONT
Nonstop1h 09mFrontier
Sun 12/286:00 amONT - LAS
Nonstop1h 07mFrontier
Deal found 12/17$108
This CheapOair deal was found by Cheapflights users on 12/18. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 12/258:13 pmLAS - ONT
Nonstop1h 04mFrontier
Mon 12/296:00 amONT - LAS
Nonstop1h 07mFrontier
Deal found 12/18$109
This Trip.com deal was found by Cheapflights users on 12/19. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 12/264:01 pmLAS - ONT
Nonstop1h 08mFrontier
Fri 1/26:00 amONT - LAS
Nonstop1h 07mFrontier
Deal found 12/19$112
This CheapOair deal was found by Cheapflights users on 12/17. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 12/244:06 pmLAS - ONT
Nonstop1h 09mFrontier
Sun 12/286:37 pmONT - LAS
Nonstop1h 11mFrontier
Deal found 12/17$119
This Frontier deal was found by Cheapflights users on 12/19. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 12/2910:44 pmSFO - ONT
Nonstop1h 28mFrontier
Mon 1/510:12 pmONT - SFO
Nonstop1h 40mFrontier
Deal found 12/19$139
This Frontier deal was found by Cheapflights users on 12/19. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 12/2610:44 pmSFO - ONT
Nonstop1h 28mFrontier
Mon 1/510:12 pmONT - SFO
Nonstop1h 40mFrontier
Deal found 12/19$149
This Super.com deal was found by Cheapflights users on 12/20. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 12/2910:44 pmSFO - ONT
Nonstop1h 28mFrontier
Fri 1/210:12 pmONT - SFO
Nonstop1h 40mFrontier
Deal found 12/20$165

Find flight deals from California to Ontario

Keep the following information in mind while searching for California to Ontario flight deals. Data was last updated December 21, 2025.

Round-trip from

$57
(Super.com)

One-way from

$30
(CheapOair)

Good round-trip deal

$157 or less

Good one-way deal

$73 or less
From California to Ontario
Search Deals
One-way flight from California to Ontario
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Price to beat on a round-trip flight from California to Ontario.
Search Deals
Price to beat on a one-way flight from California to Ontario.
Search Deals

Cheapflights Fare Finder

 
Customize your flight search to find flights from California to Ontario that fit within your specific budget. Explore options based on user searches and filter the results based on your desired price range. Find flights that match your budget for a cost-effective journey. Over the last 7 days, Cheapflights users made 2,558,603 searches. Data last updated December 21, 2025.
Use the filters below to find and compare flights from California to Ontario that are best for you.

Fly from

California

Fly to

Ontario

Route

Depart

Return

Price

Las VegasOntario

LAS - ONT

LASONT

Las Vegas Harry Reid Intl

Wed 1/7

8:45 am-9:50 am

Nonstop1h 05m

Ontario

Sun 1/11

10:18 pm-11:29 pm

Nonstop1h 11m

$58

Las VegasOntario

LAS - ONT

LASONT

Las Vegas Harry Reid Intl

Thu 1/8

6:30 am-7:36 am

Nonstop1h 06m

Ontario

Thu 1/15

4:34 pm-5:49 pm

Nonstop1h 15m

$60

Las VegasOntario

LAS - ONT

LASONT

Las Vegas Harry Reid Intl

Fri 1/23

12:21 pm-1:32 pm

Nonstop1h 11m

Ontario

Fri 2/6

10:18 am-11:31 am

Nonstop1h 13m

$63

Las VegasOntario

LAS - ONT

LASONT

Las Vegas Harry Reid Intl

Wed 1/7

8:45 am-9:50 am

Nonstop1h 05m

Ontario

Sat 1/10

3:21 pm-4:27 pm

Nonstop1h 06m

$64

Las VegasOntario

LAS - ONT

LASONT

Las Vegas Harry Reid Intl

Thu 1/8

6:30 am-7:36 am

Nonstop1h 06m

Ontario

Sat 1/10

3:21 pm-4:27 pm

Nonstop1h 06m

$70

Las VegasOntario

LAS - ONT

LASONT

Las Vegas Harry Reid Intl

Fri 1/16

6:30 am-7:37 am

Nonstop1h 07m

Ontario

Fri 1/16

10:18 pm-11:29 pm

Nonstop1h 11m

$72

Las VegasOntario

LAS - ONT

LASONT

Las Vegas Harry Reid Intl

Fri 1/30

8:15 am-9:23 am

Nonstop1h 08m

Ontario

Fri 1/30

8:48 pm-9:56 pm

Nonstop1h 08m

$90

Las VegasOntario

LAS - ONT

LASONT

Las Vegas Harry Reid Intl

Mon 1/5

8:13 pm-9:17 pm

Nonstop1h 04m

Ontario

Thu 1/8

8:14 pm-9:20 pm

Nonstop1h 06m

$99

Las VegasOntario

LAS - ONT

LASONT

Las Vegas Harry Reid Intl

Wed 2/11

5:12 pm-6:22 pm

Nonstop1h 10m

Ontario

Sun 2/15

10:18 pm-11:29 pm

Nonstop1h 11m

$104

Las VegasOntario

LAS - ONT

LASONT

Las Vegas Harry Reid Intl

Sun 1/11

6:30 am-7:36 am

Nonstop1h 06m

Ontario

Fri 1/16

10:18 pm-11:29 pm

Nonstop1h 11m

$104

Flights are sorted by cheapest round-trip flights first.

Deals found on 12/18

Showing 1-10 of 60 results
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Best time to book a flight from California to Ontario

Have a flexible travel schedule? Discover the best time to fly to Ontario from California with our price prediction graph.
Estimated round-trip price
Rates are based on past data. Find the cheapest month and day to book your flight based on your travel requirements, then search for cheap deals.

Cheapflights Insights

Everything you need to know about your flight from California to Ontario

What is the cheapest month to book a flight from California to Ontario?

Currently, February is the cheapest month in which you can book a flight from California to Ontario (average of $19). Flying from California to Ontario in September is currently the most expensive (average of $60). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

What is the cheapest time of day to fly from CA to ONT?

Find hourly flight availability from California to Ontario. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated December 21, 2025.

It’s typically best to fly out from California to Ontario at noon. Doing so could potentially save you 5% on the flight price compared to flying in the evening, which is usually more expensive.

What is the cheapest day to fly from California to Ontario?

Use this chart to determine the cheapest time to fly round-trip from California to Ontario. Price data was last updated on December 16, 2024.

Travelers seeking maximum savings on their California to Ontario flight should consider departing on Saturday evenings when fares are most often at their lowest. Friday at noon flights should be avoided if possible as fares are typically the most expensive at this time.

Reviews of airlines servicing Ontario

Get insights into the airlines that provide service to Ontario. Read reviews, discover amenities, and learn about the overall travel experience offered by airlines. Use this information to make informed decisions when choosing an airline for your flight to Ontario. Reviews last updated December 21, 2025.
See what other customers who have flown with Southwest, Delta, and United Airlines from California to Ontario have to say. Users can see the overall rating for each airline as well as how each is rated in terms of entertainment options, comfort, food, crew/service, and boarding process.
Southwest
8.0
Very good
4,257 reviews

Crew

8.6

Comfort

8.0

Entertainment

7.5

Boarding

8.1

Overall

8.0

Food

7.0

Reviews

1 / 20
8.0
Excellent

Walter,Aug 2025

OAK - SAN

Dozens of flights and I've never seen a row's beverages forgotten. I even went back and asked the attendant to check on them and nothing. I really hope it didn't have something to do with the Black mother with her kid in the row. Otherwise it was a typical Southwest flight, rapid boarding, tolerable leg room.
Southwest
8.0
Very good
4,257 reviews
Southwest
8.0
Very good
4,257 reviews

Crew

8.6

Comfort

8.0

Entertainment

7.5

Boarding

8.1

Overall

8.0

Food

7.0

Reviews

1 / 20
8.0
Excellent

Walter,Aug 2025

OAK - SAN

Dozens of flights and I've never seen a row's beverages forgotten. I even went back and asked the attendant to check on them and nothing. I really hope it didn't have something to do with the Black mother with her kid in the row. Otherwise it was a typical Southwest flight, rapid boarding, tolerable leg room.
Delta
7.9
Good
8,021 reviews
Southwest
8.0
Very good
4,257 reviews

Crew

8.6

Comfort

8.0

Entertainment

7.5

Boarding

8.1

Overall

8.0

Food

7.0

Reviews

1 / 20
8.0
Excellent

Walter,Aug 2025

OAK - SAN

Dozens of flights and I've never seen a row's beverages forgotten. I even went back and asked the attendant to check on them and nothing. I really hope it didn't have something to do with the Black mother with her kid in the row. Otherwise it was a typical Southwest flight, rapid boarding, tolerable leg room.
United Airlines
7.4
Good
9,099 reviews
Southwest
8.0
Very good
4,257 reviews

Crew

8.6

Comfort

8.0

Entertainment

7.5

Boarding

8.1

Overall

8.0

Food

7.0

Reviews

1 / 20
8.0
Excellent

Walter,Aug 2025

OAK - SAN

Dozens of flights and I've never seen a row's beverages forgotten. I even went back and asked the attendant to check on them and nothing. I really hope it didn't have something to do with the Black mother with her kid in the row. Otherwise it was a typical Southwest flight, rapid boarding, tolerable leg room.
American Airlines
7.2
Good
11,050 reviews
Southwest
8.0
Very good
4,257 reviews

Crew

8.6

Comfort

8.0

Entertainment

7.5

Boarding

8.1

Overall

8.0

Food

7.0

Reviews

1 / 20
8.0
Excellent

Walter,Aug 2025

OAK - SAN

Dozens of flights and I've never seen a row's beverages forgotten. I even went back and asked the attendant to check on them and nothing. I really hope it didn't have something to do with the Black mother with her kid in the row. Otherwise it was a typical Southwest flight, rapid boarding, tolerable leg room.
Frontier
5.8
Fair
3,082 reviews
Southwest
8.0
Very good
4,257 reviews

Crew

8.6

Comfort

8.0

Entertainment

7.5

Boarding

8.1

Overall

8.0

Food

7.0

Reviews

1 / 20
8.0
Excellent

Walter,Aug 2025

OAK - SAN

Dozens of flights and I've never seen a row's beverages forgotten. I even went back and asked the attendant to check on them and nothing. I really hope it didn't have something to do with the Black mother with her kid in the row. Otherwise it was a typical Southwest flight, rapid boarding, tolerable leg room.

Related info for your journey

Find useful and relevant information for your journey from California to Ontario. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.

  • What airport do you fly into for flights to Ontario from California?

    Located just 3.1 mi from the city center, Ontario (ONT) is the airport most travelers will use when flying to Ontario from California.

  • How long is the flight from California to Ontario?

    Frontier and Alaska Airlines can get you from California to Ontario in just under 1h 05m. Your travel time will be generally consistent. California and Ontario are separated by a distance of 197 mi. All flights are typically nonstop.

  • What are the cheapest airlines to fly from California to Ontario one-way?

    For one-way options, check prices for Frontier. According to our data, you can fly for as low as $19. Users have also found prices from $28 and $48 on United Airlines and Southwest, respectively.

  • What are the most popular routes from California to Ontario?

    When deciding which route to take from California to Ontario consider San Francisco - Ontario, San Jose - Ontario or Sacramento Intl - Ontario as they are the most popular.

  • Can I find deals for flights from California to Ontario that include hotel bookings?

    Yes. In addition to deals on California to Ontario flights, Cheapflights offers vacation packages that include both flights and hotel.

  • How can I find direct flights from California to Ontario?

    After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from California to Ontario.

  • Can I find deals for business class flights from California to Ontario?

    Yes. Cheapflights offers flight deals from California to Ontario by cabin class. In addition to browsing deals, you can also filter by cabin class on the search results page after making a search.

  • What is the cheapest month to book a flight from California to Ontario?

    Currently, February is the cheapest month in which you can book a flight from California to Ontario (average of $19). Flying from California to Ontario in September is currently the most expensive (average of $60). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

See more FAQs

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Alternative routes for California to Ontario

See prices for flight routes from nearby airports that may be better suited for you.
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Top 7 airlines flying from California to Ontario

Discover the top 7 airlines that operate flights from California to Ontario. Compare their services, reliability, and customer satisfaction ratings to choose the airline that best suits your travel preferences and needs. Over the last 7 days, Cheapflights users made 2,558,603 searches. Data last updated December 21, 2025.
AirlineCheapestAverageFlexibilityOn-time
Spirit AirlinesCheapest$22Average$88FlexibilityNo cancel feeOn-time65%
FrontierCheapest$29Average$139FlexibilityNo cancel feeOn-time62%
United AirlinesCheapest$58Average$252FlexibilityNo cancel feeOn-time69%
Alaska AirlinesCheapest$59Average$215FlexibilityNo cancel feeOn-time75%
DeltaCheapest$98Average$219FlexibilityNo cancel feeOn-timeN/A
SouthwestCheapest$112Average$276FlexibilityNo cancel feeOn-time63%
American AirlinesCheapest$186Average$206FlexibilityNo cancel feeOn-time71%

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