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San Francisco Bay Area

$39+ Cheap flights from Ontario (ONT) to San Francisco Bay Area

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 11/5. Fares are subject to change and may not be available on all flights or dates of travel.
ONT — SFO
Oct 16 — Oct 231
Thu 10/16
Thu 10/23
1 adult, Economy
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Cheap flight deals from Ontario to San Francisco Bay Area

Keep the following information in mind while searching for Ontario to San Francisco Bay Area flight deals. Data was last updated September 16, 2025.

Round-trip from

$71
(Kiwi.com)

One-way from

$39
(United Airlines)

Popular in

May

Cheapest in

October

Average price

$140
From Ontario to San Francisco Bay Area
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One-way flight from Ontario to San Francisco Bay Area
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Highest demand for flights based on searches. 16% potential increase in price ($29 potential increase over avg. RT price).
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Cheapest flight prices on average. 2% potential price decrease ($3 potential savings vs. average RT price).
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Average for round-trip flights in September 2025
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Find flight deals from Ontario to San Francisco Bay Area

Cheapest flights from Ontario to San Francisco Bay Area
Explore the most affordable flight options available from Ontario to San Francisco Bay Area. Find the lowest fares from popular airlines and budget airlines, with prices last updated on September 16, 2025.

This Kiwi.com deal was found by Cheapflights users on 9/15. 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.
Thu 10/29:46 pmONT - SFO
Nonstop1h 29mFrontier
Fri 10/310:11 pmSFO - ONT
Nonstop1h 27mFrontier
Deal found 9/15$71
This United Airlines deal was found by Cheapflights users on 9/14. 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.
Wed 10/81:53 pmONT - SFO
Nonstop1h 18mUnited Airlines
Sat 10/119:30 pmSFO - ONT
Nonstop1h 22mUnited Airlines
Deal found 9/14$77
This Cheapflightsfares deal was found by Cheapflights users on 9/14. 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 10/1010:50 pmONT - SFO
Nonstop1h 29mFrontier
Fri 10/1710:43 pmSFO - ONT
Nonstop1h 29mFrontier
Deal found 9/14$78
This Cheapflightsfares deal was found by Cheapflights users on 9/15. 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 10/1710:50 pmONT - SFO
Nonstop1h 29mFrontier
Sun 10/1910:38 pmSFO - ONT
Nonstop1h 29mFrontier
Deal found 9/15$79
This Kiwi.com deal was found by Cheapflights users on 9/15. 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 10/1010:50 pmONT - SFO
Nonstop1h 29mFrontier
Sun 10/1210:38 pmSFO - ONT
Nonstop1h 29mFrontier
Deal found 9/15$82
This Cheapflightsfares deal was found by Cheapflights users on 9/16. 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 11/710:40 pmONT - SFO
Nonstop1h 29mFrontier
Sun 11/910:11 pmSFO - ONT
Nonstop1h 29mFrontier
Deal found 9/16$86
This Cheapflightsfares deal was found by Cheapflights users on 9/15. 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 9/2610:40 pmONT - SFO
Nonstop1h 35mFrontier
Sun 10/510:11 pmSFO - ONT
Nonstop1h 27mFrontier
Deal found 9/15$87
This Cheapflightsfares deal was found by Cheapflights users on 9/15. 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.
Thu 9/189:46 pmONT - SFO
Nonstop1h 29mFrontier
Mon 9/2210:11 pmSFO - ONT
Nonstop1h 27mFrontier
Deal found 9/15$91
This Frontier deal was found by Cheapflights users on 9/15. 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 10/310:40 pmONT - SFO
Nonstop1h 35mFrontier
Sun 10/510:11 pmSFO - ONT
Nonstop1h 27mFrontier
Deal found 9/15$92
This Southwest deal was found by Cheapflights users on 9/15. 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.
Wed 10/1511:00 amONT - OAK
Nonstop1h 25mSouthwest
Wed 10/226:40 amOAK - ONT
Nonstop1h 20mSouthwest
Deal found 9/15$97
This Southwest deal was found by Cheapflights users on 9/15. 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.
Sat 10/116:10 amONT - SJC
Nonstop1h 15mSouthwest
Sat 10/113:35 pmSJC - ONT
Nonstop1h 15mSouthwest
Deal found 9/15$97
This Southwest deal was found by Cheapflights users on 9/15. 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.
Wed 10/85:45 pmONT - SJC
1 stop4h 35mSouthwest
Sat 10/113:35 pmSJC - ONT
Nonstop1h 15mSouthwest
Deal found 9/15$107

Cheapflights Fare Finder

 
Customize your flight search to find flights from Ontario to San Francisco Bay Area 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 September 16, 2025.
Use the filters below to find and compare flights from Ontario to San Francisco Bay Area that are best for you.

Fly from

Ontario

Fly to

San Francisco Bay Area

Route

Depart

Return

Price

OntarioSan Francisco

ONT - SFO

ONTSFO

Ontario

Sat 10/11

6:51 pm-8:10 pm

Nonstop1h 19m

San Francisco

Sat 10/18

10:45 am-12:13 pm

Nonstop1h 28m

$77

OntarioSan Jose

ONT - SJC

ONTSJC

Ontario

Sat 10/18

3:50 pm-5:05 pm

Nonstop1h 15m

San Jose

Mon 10/20

9:10 pm-10:25 pm

Nonstop1h 15m

$97

OntarioSan Jose

ONT - SJC

ONTSJC

Ontario

Mon 12/8

3:15 pm-4:30 pm

Nonstop1h 15m

San Jose

Tue 12/16

3:35 pm-4:50 pm

Nonstop1h 15m

$97

OntarioSan Jose

ONT - SJC

ONTSJC

Ontario

Sat 10/11

3:50 pm-5:05 pm

Nonstop1h 15m

San Jose

Sat 10/18

3:35 pm-4:50 pm

Nonstop1h 15m

$97

OntarioSan Francisco

ONT - SFO

ONTSFO

Ontario

Sun 12/14

6:00 am-7:24 am

Nonstop1h 24m

San Francisco

Sun 12/14

9:28 pm-10:49 pm

Nonstop1h 21m

$99

OntarioSan Jose

ONT - SJC

ONTSJC

Ontario

Wed 10/8

5:45 pm-10:20 pm

1 stop4h 35m

San Jose

Sat 10/11

3:35 pm-4:50 pm

Nonstop1h 15m

$107

OntarioSan Jose

ONT - SJC

ONTSJC

Ontario

Tue 10/14

2:30 pm-3:45 pm

Nonstop1h 15m

San Jose

Wed 10/15

4:20 pm-9:25 pm

1 stop5h 05m

$107

OntarioSan Jose

ONT - SJC

ONTSJC

Ontario

Tue 10/21

5:45 pm-10:20 pm

1 stop4h 35m

San Jose

Thu 10/23

7:00 am-8:15 am

Nonstop1h 15m

$107

OntarioSan Jose

ONT - SJC

ONTSJC

Ontario

Wed 10/29

8:50 am-4:00 pm

2 stops7h 10m

San Jose

Wed 11/5

10:35 am-11:55 am

Nonstop1h 20m

$112

OntarioSan Jose

ONT - SJC

ONTSJC

Ontario

Sat 10/25

5:45 am-9:50 am

1 stop4h 05m

San Jose

Sat 10/25

1:25 pm-8:50 pm

1 stop7h 25m

$122

Flights are sorted by cheapest round-trip flights first.

Deals found on 9/14

Showing 1-10 of 60 results
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Best time to book a flight from Ontario to San Francisco Bay Area

Have a flexible travel schedule? Discover the best time to fly to San Francisco Bay Area from Ontario 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 Ontario to San Francisco Bay Area

What is the cheapest month to book a flight from Ontario to San Francisco Bay Area?

Currently, January is the cheapest month in which you can book a flight from Ontario to San Francisco Bay Area (average of $276). Flying from Ontario to San Francisco Bay Area in June is currently the most expensive (average of $357). 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 ONT to XIH?

Find hourly flight availability from Ontario to San Francisco Bay Area. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated September 16, 2025.

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

Weekly flight availability from Ontario to San Francisco Bay Area

Explore weekly flight availability from Ontario to San Francisco Bay Area. Discover flights operating on different days of the week, giving you the flexibility to choose a travel day that best fits your plans. Compare info to find the most convenient option for your journey. Data last updated September 16, 2025.

The most flights from ONT to zzXIH are scheduled on a Tuesday (8 on average). You will have fewer flight options on Saturday, which is when the least amount of flights are scheduled (4 on average).

Reviews of airlines servicing San Francisco Bay Area

Get insights into the airlines that provide service to San Francisco Bay Area. 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 San Francisco Bay Area. Reviews last updated September 16, 2025.
Get a feel of what it's like to fly with Southwest, United Airlines, and American Airlines from Ontario to San Francisco Bay Area by reading reviews from past customers. You can also see how each airline stacks up in terms of entertainment options, comfort, food, crew/service, and boarding process.
Southwest
8.0
Very good
4,242 reviews

Comfort

8.0

Entertainment

7.5

Crew

8.6

Overall

8.0

Boarding

8.1

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
4,242 reviews
Southwest
8.0
Very good
4,242 reviews

Comfort

8.0

Entertainment

7.5

Crew

8.6

Overall

8.0

Boarding

8.1

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
8,924 reviews
Southwest
8.0
Very good
4,242 reviews

Comfort

8.0

Entertainment

7.5

Crew

8.6

Overall

8.0

Boarding

8.1

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
10,000 reviews
Southwest
8.0
Very good
4,242 reviews

Comfort

8.0

Entertainment

7.5

Crew

8.6

Overall

8.0

Boarding

8.1

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.
Spirit Airlines
6.3
Okay
8,019 reviews
Southwest
8.0
Very good
4,242 reviews

Comfort

8.0

Entertainment

7.5

Crew

8.6

Overall

8.0

Boarding

8.1

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
3,174 reviews
Southwest
8.0
Very good
4,242 reviews

Comfort

8.0

Entertainment

7.5

Crew

8.6

Overall

8.0

Boarding

8.1

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 Ontario to San Francisco Bay Area. 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 from for flights from Ontario to San Francisco Bay Area?

    Ontario (ONT), located 3.1 mi from the city center, is the airport you fly out of when you book flights from Ontario to San Francisco Bay Area.

  • How popular is this Ontario to San Francisco Bay Area flight route?

    Within the past month, 158 users have taken a look at flights from Ontario to San Francisco Bay Area.

  • How long is the flight from Ontario to San Francisco Bay Area?

    United Airlines and Southwest can get you from Ontario to San Francisco Bay Area in just under 1h 15m. Your travel time will be generally consistent. There are 333 mi between Ontario and San Francisco Bay Area. Most flights are nonstop.

  • What are the most popular routes from Ontario to San Francisco Bay Area?

    The most popular route from Ontario to San Francisco Bay Area is Ontario - San Francisco. You may also consider Ontario - San Jose or Ontario - Oakland.

  • What are the most reliable airlines from Ontario to San Francisco Bay Area?

    Consider Emirates (85%), SkyWest Airlines (83%) or Air Canada (73%) when booking your flight. These represent the most reliable airlines when flying from Ontario to San Francisco Bay Area.

  • What are the cheapest flights from Ontario to San Francisco Bay Area?

    The cheapest flight price from Ontario to San Francisco Bay Area is $39. On average you can expect to pay $556. The most popular route, (Ontario - San Francisco), can usually be booked for $53.

  • Can I find deals for flights from Ontario to San Francisco Bay Area that include hotel bookings?

    Yes. In addition to deals on Ontario to San Francisco Bay Area flights, Cheapflights offers vacation packages that include both flights and hotel.

  • How can I find direct flights from Ontario to San Francisco Bay Area?

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

  • Can I find deals for business class flights from Ontario to San Francisco Bay Area?

    Yes. Cheapflights offers flight deals from Ontario to San Francisco Bay Area 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 Ontario to San Francisco Bay Area?

    Currently, January is the cheapest month in which you can book a flight from Ontario to San Francisco Bay Area (average of $276). Flying from Ontario to San Francisco Bay Area in June is currently the most expensive (average of $357). 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.

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Alternative routes for Ontario to San Francisco Bay Area

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Top 8 airlines flying from Ontario to San Francisco Bay Area

Discover the top 8 airlines that operate flights from Ontario to San Francisco Bay Area. 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 September 16, 2025.
AirlineCheapestAverageFlexibilityOn-time
Spirit AirlinesCheapest$31Average$86FlexibilityNo cancel feeOn-time65%
FrontierCheapest$36Average$100FlexibilityNo cancel feeOn-time62%
United AirlinesCheapest$58Average$190FlexibilityNo cancel feeOn-time69%
Alaska AirlinesCheapest$67Average$200FlexibilityNo cancel feeOn-time75%
Avelo AirlinesCheapest$67Average$85FlexibilityNo cancel feeOn-timeN/A
DeltaCheapest$97Average$207FlexibilityNo cancel feeOn-timeN/A
SouthwestCheapest$101Average$288FlexibilityNo cancel feeOn-time63%
American AirlinesCheapest$222Average$306FlexibilityNo cancel feeOn-time71%

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