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Ontario

$34+ 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 1/27. Fares are subject to change and may not be available on all flights or dates of travel.
LAX — ONT
Nov 29 — Dec 61
Sat 11/29
Sat 12/6
1 adult, Economy
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Find 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 October 30, 2025.

This CheapOair deal was found by Cheapflights users on 10/28. 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.
Mon 12/88:13 pmLAS - ONT
Nonstop1h 04mFrontier
Tue 12/166:15 amONT - LAS
Nonstop1h 07mFrontier
Deal found 10/28$58
This Frontier deal was found by Cheapflights users on 10/29. 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 12/412:56 pmLAS - ONT
Nonstop1h 08mFrontier
Mon 12/85:18 pmONT - LAS
Nonstop1h 09mFrontier
Deal found 10/29$59
This CheapOair deal was found by Cheapflights users on 10/27. 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 12/38:13 pmLAS - ONT
Nonstop1h 04mFrontier
Sat 12/66:15 amONT - LAS
Nonstop1h 07mFrontier
Deal found 10/27$60
This Frontier deal was found by Cheapflights users on 10/29. 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 12/1112:56 pmLAS - ONT
Nonstop1h 08mFrontier
Fri 12/125:18 pmONT - LAS
Nonstop1h 09mFrontier
Deal found 10/29$71
This CheapOair deal was found by Cheapflights users on 10/29. 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.
Sat 12/68:13 pmLAS - ONT
Nonstop1h 04mFrontier
Sun 12/76:15 amONT - LAS
Nonstop1h 07mFrontier
Deal found 10/29$73
This CheapOair deal was found by Cheapflights users on 10/29. 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.
Mon 12/1512:56 pmLAS - ONT
Nonstop1h 08mFrontier
Sun 12/216:37 pmONT - LAS
Nonstop1h 11mFrontier
Deal found 10/29$78
This CheapOair deal was found by Cheapflights users on 10/28. 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 11/278:00 pmLAS - ONT
Nonstop1h 06mFrontier
Thu 12/42:59 pmONT - LAS
Nonstop1h 09mFrontier
Deal found 10/28$79
This CheapOair deal was found by Cheapflights users on 10/30. 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 12/49:03 pmSFO - ONT
Nonstop1h 26mFrontier
Wed 12/106:15 amONT - SFO
1 stop10h 36mFrontier
Deal found 10/30$82
This Frontier deal was found by Cheapflights users on 10/28. 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 11/178:51 pmLAS - ONT
Nonstop1h 06mFrontier
Tue 11/188:45 amONT - LAS
1 stop6h 39mFrontier
Deal found 10/28$82
This Frontier deal was found by Cheapflights users on 10/30. 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 12/46:00 amSFO - ONT
1 stop15h 17mFrontier
Mon 12/810:12 pmONT - SFO
Nonstop1h 40mFrontier
Deal found 10/30$83
This Kiwi.com deal was found by Cheapflights users on 10/30. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 11/148:51 pmLAS - ONT
Nonstop1h 06mFrontier
Tue 11/188:00 amONT - LAS
Nonstop1h 12mFrontier
Deal found 10/30$83
This Frontier deal was found by Cheapflights users on 10/28. 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 12/46:00 amSFO - ONT
1 stop8h 04mFrontier
Thu 12/410:12 pmONT - SFO
Nonstop1h 40mFrontier
Deal found 10/28$84

Cheap flight deals from California to Ontario

Keep the following information in mind while searching for California to Ontario flight deals. Data was last updated October 30, 2025.

Round-trip from

$57
(Kiwi.com)

One-way from

$34
(Flightnetwork)

Good round-trip deal

$123 or less

Good one-way deal

$68 or less
From California to Ontario
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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.
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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 October 30, 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

Thu 11/20

1:15 pm-2:26 pm

Nonstop1h 11m

Ontario

Thu 11/20

3:31 pm-4:44 pm

Nonstop1h 13m

$87

Las VegasOntario

LAS - ONT

LASONT

Las Vegas Harry Reid Intl

Thu 12/4

11:10 am-12:10 pm

Nonstop1h 00m

Ontario

Mon 12/8

6:50 am-7:55 am

Nonstop1h 05m

$97

Las VegasOntario

LAS - ONT

LASONT

Las Vegas Harry Reid Intl

Mon 11/17

12:59 am-9:27 pm

1 stop20h 28m

Ontario

Wed 11/19

8:00 am-9:12 am

Nonstop1h 12m

$106

Las VegasOntario

LAS - ONT

LASONT

Las Vegas Harry Reid Intl

Tue 1/13

12:45 pm-1:50 pm

Nonstop1h 05m

Ontario

Wed 1/14

5:55 am-10:15 am

1 stop4h 20m

$107

Las VegasOntario

LAS - ONT

LASONT

Las Vegas Harry Reid Intl

Wed 11/12

12:34 pm-9:29 pm

1 stop8h 55m

Ontario

Wed 11/19

12:58 am-11:18 am

1 stop10h 20m

$110

Las VegasOntario

LAS - ONT

LASONT

Las Vegas Harry Reid Intl

Sun 12/28

8:23 pm-9:27 pm

Nonstop1h 04m

Ontario

Mon 1/12

6:30 am-7:37 am

Nonstop1h 07m

$119

Las VegasOntario

LAS - ONT

LASONT

Las Vegas Harry Reid Intl

Sat 11/22

9:00 am-10:11 am

Nonstop1h 11m

Ontario

Mon 11/24

6:30 am-7:40 am

Nonstop1h 10m

$120

RenoOntario

RNO - ONT

RNOONT

Reno

Thu 11/13

7:19 pm-12:51 pm

1 stop17h 32m

Ontario

Sat 11/15

1:37 pm-6:30 pm

1 stop4h 53m

$121

RenoOntario

RNO - ONT

RNOONT

Reno

Thu 11/13

7:19 pm-12:51 pm

1 stop17h 32m

Ontario

Mon 11/17

6:00 am-7:18 pm

1 stop13h 18m

$122

RenoOntario

RNO - ONT

RNOONT

Reno

Fri 11/14

11:51 am-11:50 pm

1 stop11h 59m

Ontario

Sat 11/15

1:37 pm-6:30 pm

1 stop4h 53m

$127

Flights are sorted by cheapest round-trip flights first.

Deals found on 10/30

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 October 30, 2025.

It’s typically best to fly out from California to Ontario at noon. Doing so could potentially save you 8% 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. Wednesday 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 October 30, 2025.
See what other customers who have flown with Southwest, Avelo Airlines, 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
4,243 reviews

Overall

8.0

Entertainment

7.5

Boarding

8.1

Food

7.0

Crew

8.6

Comfort

8.0

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
4,243 reviews
Southwest
8.0
Very good
4,243 reviews

Overall

8.0

Entertainment

7.5

Boarding

8.1

Food

7.0

Crew

8.6

Comfort

8.0

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.
Avelo Airlines
7.5
Good
Southwest
8.0
Very good
4,243 reviews

Overall

8.0

Entertainment

7.5

Boarding

8.1

Food

7.0

Crew

8.6

Comfort

8.0

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
8,999 reviews
Southwest
8.0
Very good
4,243 reviews

Overall

8.0

Entertainment

7.5

Boarding

8.1

Food

7.0

Crew

8.6

Comfort

8.0

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
11,034 reviews
Southwest
8.0
Very good
4,243 reviews

Overall

8.0

Entertainment

7.5

Boarding

8.1

Food

7.0

Crew

8.6

Comfort

8.0

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
3,123 reviews
Southwest
8.0
Very good
4,243 reviews

Overall

8.0

Entertainment

7.5

Boarding

8.1

Food

7.0

Crew

8.6

Comfort

8.0

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, Southwest, and Alaska Airlines can get you from California to Ontario in just under 1h. 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 United Airlines. According to our data, you can fly for as low as $39. Users have also found prices from $49 and $79 on Southwest and Alaska Airlines, 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 October 30, 2025.
AirlineCheapestAverageFlexibilityOn-time
FrontierCheapest$24Average$124FlexibilityNo cancel feeOn-time62%
Spirit AirlinesCheapest$38Average$97FlexibilityNo cancel feeOn-time65%
United AirlinesCheapest$58Average$237FlexibilityNo cancel feeOn-time69%
Alaska AirlinesCheapest$59Average$223FlexibilityNo cancel feeOn-time75%
DeltaCheapest$98Average$215FlexibilityNo cancel feeOn-timeN/A
SouthwestCheapest$116Average$278FlexibilityNo cancel feeOn-time63%
American AirlinesCheapest$186Average$221FlexibilityNo cancel feeOn-time71%

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