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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 9/2. Fares are subject to change and may not be available on all flights or dates of travel.
ONT — SFO
Jun 21 — Jun 281
Sat 6/21
Sat 6/28
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 June 16, 2025.

Round-trip from

$52
(United Airlines)

One-way from

$39
(Southwest)

Popular in

May

Cheapest in

October

Average price

$175
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. 20% potential increase in price ($35 potential increase over avg. RT price).
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Cheapest flight prices on average. 2% potential price decrease ($4 potential savings vs. average RT price).
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Average for round-trip flights in June 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 June 16, 2025.

This Southwest deal was found by Cheapflights users on 6/14. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 8/79:55 amONT - OAK
Nonstop1h 20mSouthwest
Mon 8/115:45 pmOAK - ONT
Nonstop1h 25mSouthwest
Deal found 6/14$77
This Frontier deal was found by Cheapflights users on 6/15. 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 7/119:41 pmONT - SFO
Nonstop1h 33mFrontier
Fri 7/1810:11 pmSFO - ONT
Nonstop1h 29mFrontier
Deal found 6/15$89
This United Airlines deal was found by Cheapflights users on 6/16. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 7/146:39 pmONT - SFO
Nonstop1h 27mUnited Airlines
Wed 7/164:16 pmSFO - ONT
Nonstop1h 27mUnited Airlines
Deal found 6/16$113
This Southwest deal was found by Cheapflights users on 6/14. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 10/235:10 pmONT - SJC
Nonstop1h 15mSouthwest
Tue 10/2811:35 amSJC - ONT
Nonstop1h 20mSouthwest
Deal found 6/14$136
This Southwest deal was found by Cheapflights users on 6/14. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 8/266:20 amONT - SFO
1 stop5h 05mSouthwest
Tue 8/2612:45 pmSFO - ONT
2 stops8h 00mSouthwest
Deal found 6/14$156
This American Airlines deal was found by Cheapflights users on 6/16. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 6/216:23 amONT - SFO
1 stop6h 14mAmerican Airlines
Sat 6/213:23 pmSFO - ONT
1 stop6h 15mAmerican Airlines
Deal found 6/16$181
This CheapOair deal was found by Cheapflights users on 6/14. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 6/285:13 pmONT - SJC
1 stop24h 47mFrontier
Mon 6/302:18 pmSJC - ONT
1 stop26h 00mFrontier
Deal found 6/14$181
This American Airlines deal was found by Cheapflights users on 6/16. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 7/16:23 amONT - STS
1 stop6h 17mAmerican Airlines
Sat 7/54:16 pmSTS - ONT
1 stop5h 22mAmerican Airlines
Deal found 6/16$199
This Justfly.com deal was found by Cheapflights users on 6/16. 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 Justfly.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 11/137:25 amONT - SJC
1 stop9h 13mAlaska Airlines
Wed 11/198:00 amSJC - ONT
1 stop15h 56mAlaska Airlines
Deal found 6/16$261
This American Airlines deal was found by Cheapflights users on 6/14. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 10/311:26 pmONT - SJC
1 stop5h 08mAmerican Airlines
Mon 11/37:24 pmSJC - ONT
1 stop19h 32mAmerican Airlines
Deal found 6/14$265
This Alaska Airlines deal was found by Cheapflights users on 6/15. 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 Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 8/127:30 amONT - OAK
1 stop25h 18mAlaska Airlines
Sat 8/168:00 amOAK - ONT
1 stop15h 59mAlaska Airlines
Deal found 6/15$273
This Orbitz deal was found by Cheapflights users on 6/15. 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 Orbitz is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 7/212:59 amONT - SJC
1 stop10h 19mMultiple Airlines
Tue 7/83:24 pmSJC - ONT
1 stop8h 49mMultiple Airlines
Deal found 6/15$302

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 June 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

OntarioOakland

ONT - OAK

ONTOAK

Ontario

Thu 8/7

9:55 am-11:15 am

Nonstop1h 20m

Oakland

Mon 8/11

5:45 pm-7:10 pm

Nonstop1h 25m

$77

OntarioSan Francisco

ONT - SFO

ONTSFO

Ontario

Fri 7/11

9:41 pm-11:14 pm

Nonstop1h 33m

San Francisco

Fri 7/18

10:11 pm-11:40 pm

Nonstop1h 29m

$89

OntarioSan Francisco

ONT - SFO

ONTSFO

Ontario

Mon 7/14

6:39 pm-8:06 pm

Nonstop1h 27m

San Francisco

Wed 7/16

4:16 pm-5:43 pm

Nonstop1h 27m

$113

OntarioSan Jose

ONT - SJC

ONTSJC

Ontario

Thu 10/23

5:10 pm-6:25 pm

Nonstop1h 15m

San Jose

Tue 10/28

11:35 am-12:55 pm

Nonstop1h 20m

$136

OntarioSan Francisco

ONT - SFO

ONTSFO

Ontario

Tue 8/26

6:20 am-11:25 am

1 stop5h 05m

San Francisco

Tue 8/26

4:45 pm-9:00 pm

1 stop4h 15m

$151

OntarioSan Jose

ONT - SJC

ONTSJC

Ontario

Sat 6/28

5:13 pm-6:00 pm

1 stop24h 47m

San Jose

Mon 6/30

2:18 pm-4:18 pm

1 stop26h 00m

$181

OntarioSan Francisco

ONT - SFO

ONTSFO

Ontario

Thu 7/10

4:45 pm-11:42 pm

1 stop6h 57m

San Francisco

Sat 7/12

8:00 am-12:00 pm

1 stop4h 00m

$187

OntarioSanta Rosa

ONT - STS

ONTSTS

Ontario

Tue 7/1

6:23 am-12:40 pm

1 stop6h 17m

Santa Rosa Sonoma County

Sat 7/5

4:16 pm-9:38 pm

1 stop5h 22m

$199

OntarioSan Jose

ONT - SJC

ONTSJC

Ontario

Thu 11/13

7:25 am-4:38 pm

1 stop9h 13m

San Jose

Wed 11/19

8:00 am-11:56 pm

1 stop15h 56m

$261

OntarioSan Jose

ONT - SJC

ONTSJC

Ontario

Fri 10/31

1:26 pm-6:34 pm

1 stop5h 08m

San Jose

Mon 11/3

7:24 pm-2:56 pm

1 stop19h 32m

$265

Flights are sorted by cheapest round-trip flights first.

Deals found on 6/16

Showing 1-10 of 40 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 $362). 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 June 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 June 16, 2025.

The most flights from ONT to zzXIH are scheduled on a Monday (9 on average). You will have fewer flight options on Saturday, which is when the least amount of flights are scheduled (7 on average).

Rainfall in San Francisco Bay Area by month

Plan your trip to San Francisco Bay Area by taking into account the average rainfall totals by month.

In terms of precipitation, rainfall in San Francisco Bay Area ranges from 0.0 - 4.4 inches per month. January is typically the wettest month, when rainfall can reach 4.4 in. July is typically the driest time to visit San Francisco Bay Area when rainfall is around 0.0 in.

Temperature in San Francisco Bay Area by month

Plan your trip to San Francisco Bay Area by taking into account the average temperature totals by month.

If weather is an important factor for your trip to San Francisco Bay Area, use this chart to help with planning. For those seeking warmer temperatures, September is the ideal time of year to visit, when temperatures reach an average of 62.6 F. Travelers looking to avoid the cold should look outside of January, when temperatures are typically at their lowest (around 51.8 F).

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 June 16, 2025.
Read reviews from past customers who have flown Alaska Airlines, Southwest and Delta from Ontario to San Francisco Bay Area. You can also see how each airline stacks up in terms of entertainment options, comfort, food, crew/service, and boarding process.
Alaska Airlines
8.0
Very good
10,000 reviews

Crew

8.5

Entertainment

7.1

Overall

8.0

Boarding

8.1

Food

7.1

Comfort

7.8

Reviews

1 / 20
10.0
Excellent

James,Apr 2025

LAX - SFO

Good flight except the uncontrollable cold air from the ceiling.
Alaska Airlines
8.0
Very good
10,000 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Crew

8.5

Entertainment

7.1

Overall

8.0

Boarding

8.1

Food

7.1

Comfort

7.8

Reviews

1 / 20
10.0
Excellent

James,Apr 2025

LAX - SFO

Good flight except the uncontrollable cold air from the ceiling.
Southwest
8.0
Very good
4,278 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Crew

8.5

Entertainment

7.1

Overall

8.0

Boarding

8.1

Food

7.1

Comfort

7.8

Reviews

1 / 20
10.0
Excellent

James,Apr 2025

LAX - SFO

Good flight except the uncontrollable cold air from the ceiling.
Delta
8.0
Very good
7,963 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Crew

8.5

Entertainment

7.1

Overall

8.0

Boarding

8.1

Food

7.1

Comfort

7.8

Reviews

1 / 20
10.0
Excellent

James,Apr 2025

LAX - SFO

Good flight except the uncontrollable cold air from the ceiling.
Hawaiian Airlines
7.9
Good
2,500 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Crew

8.5

Entertainment

7.1

Overall

8.0

Boarding

8.1

Food

7.1

Comfort

7.8

Reviews

1 / 20
10.0
Excellent

James,Apr 2025

LAX - SFO

Good flight except the uncontrollable cold air from the ceiling.
United Airlines
7.4
Good
8,801 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Crew

8.5

Entertainment

7.1

Overall

8.0

Boarding

8.1

Food

7.1

Comfort

7.8

Reviews

1 / 20
10.0
Excellent

James,Apr 2025

LAX - SFO

Good flight except the uncontrollable cold air from the ceiling.

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, 180 users have taken a look at flights from Ontario to San Francisco Bay Area.

  • What are the cheapest airlines to fly from Ontario to San Francisco Bay Area one-way?

    To fly one-way, consider booking your trip with Southwest, which is currently one of the cheapest options available, starting at $39. Frontier flights start at $54 while deals on United Airlines start at $61 one-way.

  • 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 (98%), SkyWest Airlines (92%) or Air Canada (88%) 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 $28. On average you can expect to pay $436. The most popular route, (Ontario - San Francisco), can usually be booked for $52.

  • 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 $362). 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

See prices for flight routes from nearby airports that may be better suited for you.
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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 June 16, 2025.
AirlineCheapestAverageFlexibilityOn-time
FrontierCheapest$30Average$89FlexibilityNo cancel feeOn-time62%
Spirit AirlinesCheapest$36Average$82FlexibilityNo cancel feeOn-time65%
United AirlinesCheapest$58Average$195FlexibilityNo cancel feeOn-time69%
Alaska AirlinesCheapest$67Average$288FlexibilityNo cancel feeOn-time75%
Avelo AirlinesCheapest$67Average$86FlexibilityNo cancel feeOn-timeN/A
DeltaCheapest$85Average$197FlexibilityNo cancel feeOn-timeN/A
SouthwestCheapest$113Average$292FlexibilityNo cancel feeOn-time63%
American AirlinesCheapest$232Average$282FlexibilityNo cancel feeOn-time71%

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