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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 1/2. Fares are subject to change and may not be available on all flights or dates of travel.
LAX — ONT
Dec 27 — Jan 31
Fri 12/27
Fri 1/3
1 adult, Economy
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Cheap flight deals from California to Ontario

Discover tips and strategies to find the most affordable flight options for your journey from California (USCA) to Ontario (ONT). Learn about various techniques such as flexible date searches, comparing prices across and setting up price alerts. Use these methods to find the cheapest flights available for your travel needs. Data last updated December 22, 2024.

Round-trip from

$48
(Cheapflightsfares)

One-way from

$37
(Mytrip)
From California to Ontario
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One-way flight from California to Ontario
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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 December 22, 2024.

This Mytrip deal was found by Cheapflights users on 12/21. 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 Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 12/297:00 amLAS - ONT
Nonstop1h 06mFrontier
Tue 1/77:45 amONT - LAS
1 stop6h 46mFrontier
Deal found 12/21$87
This Cheapflightsfares deal was found by Cheapflights users on 12/21. 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 Cheapflightsfares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 12/295:32 pmSFO - ONT
Nonstop1h 25mFrontier
Mon 1/612:00 pmONT - SFO
Nonstop1h 29mFrontier
Deal found 12/21$93
This Cheapflightsfares deal was found by Cheapflights users on 12/21. 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 Cheapflightsfares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 12/2710:39 amSMF - ONT
Nonstop1h 26mFrontier
Sun 1/512:42 pmONT - SMF
Nonstop1h 25mFrontier
Deal found 12/21$102
This Gotogate 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 Gotogate is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 12/297:26 pmSJC - ONT
1 stop11h 43mFrontier
Mon 12/3012:59 amONT - SJC
1 stop9h 21mFrontier
Deal found 12/20$153
This Mytrip deal was found by Cheapflights users on 12/21. 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 Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 12/267:00 amSTS - ONT
Nonstop1h 26mAvelo Airlines
Thu 1/29:11 amONT - STS
Nonstop1h 33mAvelo Airlines
Deal found 12/21$193
This Delta deal was found by Cheapflights users on 12/22. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 12/306:00 amRNO - ONT
1 stop6h 20mDelta
Sat 1/45:30 amONT - RNO
1 stop6h 59mDelta
Deal found 12/22$264
This United Airlines deal was found by Cheapflights users on 12/21. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 12/286:15 amRNO - ONT
1 stop3h 43mUnited Airlines
Mon 12/306:00 amONT - RNO
1 stop3h 57mUnited Airlines
Deal found 12/21$324
This Southwest deal was found by Cheapflights users on 12/21. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 12/317:00 amRNO - ONT
1 stop5h 50mSouthwest
Wed 1/16:15 amONT - RNO
1 stop3h 20mSouthwest
Deal found 12/21$333
This United Airlines deal was found by Cheapflights users on 12/22. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 12/279:27 pmSFO - ONT
Nonstop1h 33mUnited Airlines
Wed 1/810:47 amONT - SFO
Nonstop1h 33mUnited Airlines
Deal found 12/22$361
This Travelocity deal was found by Cheapflights users on 12/21. 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 Travelocity is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 12/2710:39 amSMF - ONT
Nonstop1h 26mMultiple Airlines
Sun 1/58:32 pmONT - SMF
2 stops13h 18mMultiple Airlines
Deal found 12/21$391
This United Airlines deal was found by Cheapflights users on 12/21. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 12/227:25 pmACV - ONT
1 stop3h 35mUnited Airlines
Fri 12/2710:39 amONT - ACV
1 stop4h 07mUnited Airlines
Deal found 12/21$404
This Southwest deal was found by Cheapflights users on 12/21. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 12/266:00 pmSMF - ONT
1 stop5h 00mSouthwest
Sat 1/46:40 pmONT - SMF
1 stop4h 40mSouthwest
Deal found 12/21$428

Find flights from California to Ontario within your budget

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 22, 2024.

Fly from

Any airport

Fly to

Any airport

Route

Depart

Return

Price

Las VegasOntario

LAS - ONT

LASONT

Las Vegas Harry Reid Intl

Wed 1/15

10:36 am-11:44 am

Nonstop1h 08m

Ontario

Thu 1/16

6:50 pm-8:00 pm

Nonstop1h 10m

$50

San FranciscoOntario

SFO - ONT

SFOONT

San Francisco

Fri 1/24

10:03 pm-11:31 pm

Nonstop1h 28m

Ontario

Mon 1/27

6:45 am-8:20 am

Nonstop1h 35m

$58

SacramentoOntario

SMF - ONT

SMFONT

Sacramento Intl

Fri 1/3

10:39 am-12:05 pm

Nonstop1h 26m

Ontario

Mon 1/6

8:09 am-9:39 am

Nonstop1h 30m

$82

Santa RosaOntario

STS - ONT

STSONT

Santa Rosa Sonoma County

Sun 2/23

7:00 am-8:26 am

Nonstop1h 26m

Ontario

Thu 2/27

9:11 am-10:44 am

Nonstop1h 33m

$83

San JoseOntario

SJC - ONT

SJCONT

San Jose

Thu 1/9

5:23 pm-7:14 am

1 stop13h 51m

Ontario

Sun 1/12

8:59 pm-4:19 pm

1 stop19h 20m

$107

San FranciscoOntario

SFO - ONT

SFOONT

San Francisco

Sat 1/25

8:25 am-9:51 am

Nonstop1h 26m

Ontario

Sat 2/8

6:15 am-7:46 am

Nonstop1h 31m

$117

San FranciscoOntario

SFO - ONT

SFOONT

San Francisco

Fri 1/31

11:00 am-6:13 pm

2 stops7h 13m

Ontario

Sun 2/2

6:45 am-8:20 am

Nonstop1h 35m

$140

SacramentoOntario

SMF - ONT

SMFONT

Sacramento Intl

Sat 2/1

5:45 am-12:26 pm

1 stop6h 41m

Ontario

Mon 2/3

6:00 am-12:27 pm

1 stop6h 27m

$176

San JoseOntario

SJC - ONT

SJCONT

San Jose

Tue 1/7

8:55 am-10:10 am

Nonstop1h 15m

Ontario

Tue 1/7

2:05 pm-3:20 pm

Nonstop1h 15m

$193

SacramentoOntario

SMF - ONT

SMFONT

Sacramento Intl

Sat 1/25

12:33 pm-7:09 pm

1 stop6h 36m

Ontario

Mon 1/27

4:06 pm-10:39 pm

1 stop6h 33m

$201

Flights are sorted by cheapest round-trip flights first.

Deals found on 12/22

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.

Travel insights for flights from California to Ontario

Get recent, data-driven insights about flights from California to Ontario including ideal travel times, pricing trends, and more.

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

Currently, August is the cheapest month in which you can book a flight from California to Ontario (average of $246). Flying from California to Ontario in March is currently the most expensive (average of $317). 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 22, 2024.

Regardless of the time of day you decide to fly, the ticket price will remain around the same. Book flights from California to Ontario as you normally would.

Rainfall in Ontario by month

Plan your trip to Ontario by taking into account the average rainfall totals by month.

In terms of precipitation, rainfall in Ontario ranges from 0.1 - 3.4 inches per month. February is typically the wettest month, when rainfall can reach 3.4 in. June is typically the driest time to visit Ontario when rainfall is around 0.1 in.

Temperature in Ontario by month

Plan your trip to Ontario by taking into account the average temperature totals by month.

If weather is an important factor for your trip to Ontario, use this chart to help with planning. For those seeking warmer temperatures, August is the ideal time of year to visit, when temperatures reach an average of 78.8 F. Travelers looking to avoid the cold should look outside of December, when temperatures are typically at their lowest (around 53.6 F).

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 22, 2024.
To help decide which airline to fly from California to Ontario, see what other customers have to say about Frontier, American Airlines and Delta. Users have also rated airlines in terms of entertainment options, comfort, food, crew/service, and boarding process.
Southwest
8.1
Very good
4,804 reviews

Crew

8.7

Boarding

8.2

Entertainment

7.7

Overall

8.1

Food

7.2

Comfort

8.1

Reviews

1 / 10

No issues. I needed pre boarding and I was able to get it without issue

Southwest
8.1
Very good
4,804 reviews
Southwest
8.1
Very good
4,804 reviews

Crew

8.7

Boarding

8.2

Entertainment

7.7

Overall

8.1

Food

7.2

Comfort

8.1

Reviews

1 / 10

No issues. I needed pre boarding and I was able to get it without issue

Alaska Airlines
8.0
Very good
9,537 reviews
Southwest
8.1
Very good
4,804 reviews

Crew

8.7

Boarding

8.2

Entertainment

7.7

Overall

8.1

Food

7.2

Comfort

8.1

Reviews

1 / 10

No issues. I needed pre boarding and I was able to get it without issue

Delta
8.0
Very good
8,594 reviews
Southwest
8.1
Very good
4,804 reviews

Crew

8.7

Boarding

8.2

Entertainment

7.7

Overall

8.1

Food

7.2

Comfort

8.1

Reviews

1 / 10

No issues. I needed pre boarding and I was able to get it without issue

Avelo Airlines
7.5
Good
74 reviews
Southwest
8.1
Very good
4,804 reviews

Crew

8.7

Boarding

8.2

Entertainment

7.7

Overall

8.1

Food

7.2

Comfort

8.1

Reviews

1 / 10

No issues. I needed pre boarding and I was able to get it without issue

United Airlines
7.4
Good
9,028 reviews
Southwest
8.1
Very good
4,804 reviews

Crew

8.7

Boarding

8.2

Entertainment

7.7

Overall

8.1

Food

7.2

Comfort

8.1

Reviews

1 / 10

No issues. I needed pre boarding and I was able to get it without issue

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.

  • 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 $37. Users have also found prices from $59 and $79 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, August is the cheapest month in which you can book a flight from California to Ontario (average of $246). Flying from California to Ontario in March is currently the most expensive (average of $317). 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 22, 2024.
AirlineCheapestAverageFlexibilityOn-time
FrontierCheapest$37Average$100FlexibilityNo cancel feeOn-time62%
Spirit AirlinesCheapest$37Average$118FlexibilityNo cancel feeOn-time65%
DeltaCheapest$45Average$234FlexibilityNo cancel feeOn-timeN/A
Alaska AirlinesCheapest$55Average$332FlexibilityNo cancel feeOn-time75%
Breeze AirwaysCheapest$78Average$150FlexibilityNo cancel feeOn-timeN/A
United AirlinesCheapest$98Average$325FlexibilityNo cancel feeOn-time69%
SouthwestCheapest$191Average$282FlexibilityNo cancel feeOn-time63%
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