HomeSearch by dateVacation packagesHotelsFlight dealsCar rentalTravel tips & news
San Francisco Bay Area

$68+ 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 2/18. Fares are subject to change and may not be available on all flights or dates of travel.
ONT — SFO
Feb 7 — Feb 141
Sat 2/7
Sat 2/14
1 adult, Economy
We work with more than 300 partners to bring you better travel deals

Find cheap flights from Ontario to San Francisco Bay Area with Cheapflights

1. Tell us where you want to go

Enter your travel information like dates, passengers, trip type (one-way or round trip), and preferred cabin class then click “Find deals”

2. Select your favorite providers

We find the providers serving your travel needs. Choose up to four travel providers to compare side-by-side for flights, hotels, or car rentals.

3. Compare prices and book

Review each provider’s pricing and select the best option for you! Book through your favorite provider’s website for a seamless experience.

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 January 8, 2026.

Most accurate provider

CheapOair
3 stars

Most trusted provider

CheapOair
3 stars

Round-trip from

$104
(Frontier)

One-way from

$68
(Super.com)

Popular in

November

Cheapest in

January

Average price

$130
Provider with most accurate pricing for Los Angeles-San Francisco flight deals.
Search Deals
Provider most trusted by Cheapflights users for Los Angeles-San Francisco flights.
Search Deals
From Ontario to San Francisco Bay Area
Search Deals
One-way flight from Ontario to San Francisco Bay Area
Search Deals
Highest demand for flights based on searches. 12% potential increase in price ($24 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 1% potential price decrease ($3 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in January 2026
Search Deals

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 January 8, 2026.

This Frontier deal was found by Cheapflights users on 1/6. 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 4/310:12 pmONT - SFO
Nonstop1h 40mFrontier
Mon 4/610:03 pmSFO - ONT
Nonstop1h 28mFrontier
Deal found 1/6$104
This Kiwi.com deal was found by Cheapflights users on 1/6. 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.
Wed 4/84:22 pmONT - STS
Nonstop2h 00mAlaska Airlines
Sun 4/122:18 pmSTS - ONT
Nonstop1h 30mAlaska Airlines
Deal found 1/6$126
This Alaska Airlines deal was found by Cheapflights users on 1/8. 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.
Thu 3/194:22 pmONT - STS
Nonstop2h 00mAlaska Airlines
Sun 3/292:18 pmSTS - ONT
Nonstop1h 30mAlaska Airlines
Deal found 1/8$127
This Frontier deal was found by Cheapflights users on 1/7. 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 3/139:06 amONT - SFO
Nonstop1h 42mFrontier
Mon 3/168:53 amSFO - ONT
Nonstop1h 29mFrontier
Deal found 1/7$128
This CheapOair deal was found by Cheapflights users on 1/7. 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 2/182:06 pmONT - SFO
1 stop19h 47mFrontier
Sat 2/216:15 amSFO - ONT
1 stop17h 44mFrontier
Deal found 1/7$129
This Kiwi.com deal was found by Cheapflights users on 1/7. 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.
Wed 2/187:17 pmONT - SFO
1 stop12h 31mFrontier
Thu 2/268:43 amSFO - ONT
1 stop4h 28mFrontier
Deal found 1/7$131
This Kiwi.com deal was found by Cheapflights users on 1/7. 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.
Wed 2/187:17 pmONT - SFO
1 stop12h 31mFrontier
Wed 2/257:20 amSFO - ONT
1 stop14h 14mFrontier
Deal found 1/7$132
This Kiwi.com deal was found by Cheapflights users on 1/7. 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 1/3010:18 amONT - SFO
1 stop8h 42mFrontier
Mon 2/21:49 pmSFO - ONT
1 stop5h 21mFrontier
Deal found 1/7$133
This Kiwi.com deal was found by Cheapflights users on 1/7. 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.
Wed 2/182:06 pmONT - SFO
1 stop4h 14mFrontier
Tue 2/247:15 pmSFO - ONT
1 stop18h 37mFrontier
Deal found 1/7$134
This Super.com deal was found by Cheapflights users on 1/6. 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 3/279:06 amONT - SFO
Nonstop1h 42mFrontier
Mon 3/308:53 amSFO - ONT
Nonstop1h 29mFrontier
Deal found 1/6$136
This Alaska Airlines deal was found by Cheapflights users on 1/8. 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.
Thu 3/264:22 pmONT - STS
Nonstop2h 00mAlaska Airlines
Sun 3/292:18 pmSTS - ONT
Nonstop1h 30mAlaska Airlines
Deal found 1/8$137
This CheapOair deal was found by Cheapflights users on 1/7. 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 1/228:48 pmONT - SFO
1 stop20h 12mFrontier
Sat 1/314:46 pmSFO - ONT
1 stop21h 07mFrontier
Deal found 1/7$137

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 January 8, 2026.
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

OntarioSanta Rosa

ONT - STS

ONTSTS

Ontario

Tue 3/24

4:22 pm-6:22 pm

Nonstop2h 00m

Santa Rosa Sonoma County

Thu 3/26

2:12 pm-3:42 pm

Nonstop1h 30m

$157

OntarioSanta Rosa

ONT - STS

ONTSTS

Ontario

Thu 1/29

9:59 am-3:53 pm

1 stop5h 54m

Santa Rosa Sonoma County

Sun 2/1

4:23 pm-10:13 pm

1 stop5h 50m

$170

OntarioSanta Rosa

ONT - STS

ONTSTS

Ontario

Fri 3/27

4:22 pm-6:22 pm

Nonstop2h 00m

Santa Rosa Sonoma County

Sun 3/29

2:18 pm-3:48 pm

Nonstop1h 30m

$177

OntarioSanta Rosa

ONT - STS

ONTSTS

Ontario

Tue 4/14

4:22 pm-6:22 pm

Nonstop2h 00m

Santa Rosa Sonoma County

Fri 4/17

7:02 pm-8:23 pm

1 stop25h 21m

$180

OntarioSan Jose

ONT - SJC

ONTSJC

Ontario

Fri 3/6

3:30 pm-10:05 pm

1 stop6h 35m

San Jose

Sat 3/7

2:25 pm-10:37 pm

1 stop8h 12m

$185

OntarioOakland

ONT - OAK

ONTOAK

Ontario

Thu 1/29

11:53 am-4:23 pm

1 stop28h 30m

Oakland

Mon 2/2

5:17 pm-8:36 pm

1 stop27h 19m

$186

OntarioSan Francisco

ONT - SFO

ONTSFO

Ontario

Tue 2/17

5:00 pm-9:30 am

2 stops16h 30m

San Francisco

Sat 2/21

5:55 am-10:37 pm

1 stop16h 42m

$191

OntarioSan Francisco

ONT - SFO

ONTSFO

Ontario

Wed 2/18

5:00 pm-9:30 am

2 stops16h 30m

San Francisco

Tue 2/24

5:55 am-1:54 pm

1 stop7h 59m

$191

OntarioSan Francisco

ONT - SFO

ONTSFO

Ontario

Fri 2/20

5:00 pm-9:30 am

2 stops16h 30m

San Francisco

Mon 2/23

8:10 pm-1:54 pm

1 stop17h 44m

$191

OntarioSanta Rosa

ONT - STS

ONTSTS

Ontario

Fri 3/27

4:22 pm-6:22 pm

Nonstop2h 00m

Santa Rosa Sonoma County

Mon 3/30

2:12 pm-3:42 pm

Nonstop1h 30m

$197

Flights are sorted by cheapest round-trip flights first.

Deals found on 1/6

Showing 1-10 of 60 results
1
2
3
...
6

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 $18). Flying from Ontario to San Francisco Bay Area in November is currently the most expensive (average of $62). 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 January 8, 2026.

One of the essential ways to save on airfare from Ontario to San Francisco Bay Area is to remain as flexible as possible. Flights that are in the afternoon tend to be the most expensive. A flight in the evening could potentially save you up to 39% on airfare.

What is the cheapest day to fly from Ontario to San Francisco Bay Area?

Use this chart to determine the cheapest time to fly round-trip from Ontario to San Francisco Bay Area. Price data was last updated on January 3, 2026.

Travelers seeking maximum savings on their Ontario to San Francisco Bay Area flight should consider departing on Friday mornings when fares are most often at their lowest. Sunday at noon flights should be avoided if possible as fares are typically the most expensive at this time.

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 January 8, 2026.

The most flights from ONT to zzXIH are scheduled on a Thursday (7 on average). You will have fewer flight options on Tuesday, which is when the least amount of flights are scheduled (2 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 January 8, 2026.
Get a feel of what it's like to fly with Alaska Airlines, Southwest, and United 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.
Alaska Airlines
8.0
Very good
11,672 reviews

Boarding

8.1

Comfort

7.8

Food

7.1

Crew

8.5

Entertainment

7.0

Overall

8.0

Reviews

1 / 20
6.0
Good

Hannah,Aug 2025

SFO - SAN

Ticket said TSA pre check, but then the TSA agent said that Alaska Airlines has not actually entered the pre check information for the ticket, so I had to use regular security. During boarding, I have a disability and need to board early. The Alaska Airlines employee announced disability boarding, but then immediately announced 2 other groups to board, so I still had to fight the crowds. On the plane, the stewardess was brusk and rude. Seats were very uncomfortable, especially on lower back.
Alaska Airlines
8.0
Very good
11,672 reviews
Alaska Airlines
8.0
Very good
11,672 reviews

Boarding

8.1

Comfort

7.8

Food

7.1

Crew

8.5

Entertainment

7.0

Overall

8.0

Reviews

1 / 20
6.0
Good

Hannah,Aug 2025

SFO - SAN

Ticket said TSA pre check, but then the TSA agent said that Alaska Airlines has not actually entered the pre check information for the ticket, so I had to use regular security. During boarding, I have a disability and need to board early. The Alaska Airlines employee announced disability boarding, but then immediately announced 2 other groups to board, so I still had to fight the crowds. On the plane, the stewardess was brusk and rude. Seats were very uncomfortable, especially on lower back.
Southwest
8.0
Very good
4,250 reviews
Alaska Airlines
8.0
Very good
11,672 reviews

Boarding

8.1

Comfort

7.8

Food

7.1

Crew

8.5

Entertainment

7.0

Overall

8.0

Reviews

1 / 20
6.0
Good

Hannah,Aug 2025

SFO - SAN

Ticket said TSA pre check, but then the TSA agent said that Alaska Airlines has not actually entered the pre check information for the ticket, so I had to use regular security. During boarding, I have a disability and need to board early. The Alaska Airlines employee announced disability boarding, but then immediately announced 2 other groups to board, so I still had to fight the crowds. On the plane, the stewardess was brusk and rude. Seats were very uncomfortable, especially on lower back.
United Airlines
7.4
Good
9,142 reviews
Alaska Airlines
8.0
Very good
11,672 reviews

Boarding

8.1

Comfort

7.8

Food

7.1

Crew

8.5

Entertainment

7.0

Overall

8.0

Reviews

1 / 20
6.0
Good

Hannah,Aug 2025

SFO - SAN

Ticket said TSA pre check, but then the TSA agent said that Alaska Airlines has not actually entered the pre check information for the ticket, so I had to use regular security. During boarding, I have a disability and need to board early. The Alaska Airlines employee announced disability boarding, but then immediately announced 2 other groups to board, so I still had to fight the crowds. On the plane, the stewardess was brusk and rude. Seats were very uncomfortable, especially on lower back.
American Airlines
7.2
Good
11,097 reviews
Alaska Airlines
8.0
Very good
11,672 reviews

Boarding

8.1

Comfort

7.8

Food

7.1

Crew

8.5

Entertainment

7.0

Overall

8.0

Reviews

1 / 20
6.0
Good

Hannah,Aug 2025

SFO - SAN

Ticket said TSA pre check, but then the TSA agent said that Alaska Airlines has not actually entered the pre check information for the ticket, so I had to use regular security. During boarding, I have a disability and need to board early. The Alaska Airlines employee announced disability boarding, but then immediately announced 2 other groups to board, so I still had to fight the crowds. On the plane, the stewardess was brusk and rude. Seats were very uncomfortable, especially on lower back.
Frontier
5.7
Fair
3,061 reviews
Alaska Airlines
8.0
Very good
11,672 reviews

Boarding

8.1

Comfort

7.8

Food

7.1

Crew

8.5

Entertainment

7.0

Overall

8.0

Reviews

1 / 20
6.0
Good

Hannah,Aug 2025

SFO - SAN

Ticket said TSA pre check, but then the TSA agent said that Alaska Airlines has not actually entered the pre check information for the ticket, so I had to use regular security. During boarding, I have a disability and need to board early. The Alaska Airlines employee announced disability boarding, but then immediately announced 2 other groups to board, so I still had to fight the crowds. On the plane, the stewardess was brusk and rude. Seats were very uncomfortable, especially on lower back.

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, 127 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?

    Alaska Airlines, American Airlines, and Delta can get you from Ontario to San Francisco Bay Area in just under 2h. Your travel time can differ by up to 4h 35m. There are 423 mi between Ontario and San Francisco Bay Area. When browsing for deals, the options you’ll see will be for both nonstop flights and flights with stops.

  • 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 Frontier, which is currently one of the cheapest options available, starting at $19. Alaska Airlines flights start at $29 while deals on United Airlines start at $36 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 United Airlines (78%), Frontier (75%) or Air Canada (72%) 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 $59. On average you can expect to pay $722. The most popular route, (Ontario - San Francisco), can usually be booked for $104.

  • 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 $18). Flying from Ontario to San Francisco Bay Area in November is currently the most expensive (average of $62). 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

Browse thousands of different options on Cheapflights for your next trip

Toggle through the tabs below to find thousands of options on Cheapflights for your next trip.

Alternative routes for Ontario to San Francisco Bay Area

See prices for flight routes from nearby airports that may be better suited for you.
San Francisco to Las Vegas flights
San Francisco to Ontario flights
Los Angeles to Las Vegas flights
San Jose to Los Angeles flights
Ontario to San Francisco flights
San Francisco to Santa Ana flights
Burbank to Las Vegas flights
San Francisco to Los Angeles flights
Santa Ana to Las Vegas flights
Los Angeles to San Francisco flights
Santa Ana to San Francisco flights
Los Angeles to San Jose flights
San Jose to Las Vegas flights
San Francisco to Palm Springs flights
San Francisco to San Diego flights
San Francisco to Burbank flights
Sacramento to Las Vegas flights
San Diego to San Francisco flights
Ontario to Las Vegas flights
San Diego to Las Vegas flights
Oakland to Las Vegas flights
Los Angeles to Reno flights
San Jose to Ontario flights
Burbank to San Francisco flights
San Jose to Santa Ana flights
Ontario to San Jose flights
Sacramento to Los Angeles flights
Sacramento to Ontario flights
Sacramento to Santa Ana flights
Ontario to Sacramento flights
San Jose to San Diego flights
Los Angeles to Sacramento flights
Stockton to Las Vegas flights
Santa Ana to San Jose flights
Oakland to Santa Ana flights
San Francisco to Long Beach flights
Las Vegas to Los Angeles flights
Las Vegas to Santa Ana flights
Burbank to Reno flights
Oakland to San Diego flights
Santa Ana to Reno flights
Oakland to Los Angeles flights
Santa Rosa to Las Vegas flights
Santa Ana to Sacramento flights
Las Vegas to San Francisco flights
Fresno to Las Vegas flights
San Jose to Palm Springs flights
Ontario to Reno flights
Las Vegas to Burbank flights
Sacramento to San Diego flights

Top 6 airlines flying from Ontario to San Francisco Bay Area

Discover the top 6 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 January 8, 2026.
AirlineCheapestAverageFlexibilityOn-time
FrontierCheapest$36Average$109FlexibilityNo cancel feeOn-time62%
Spirit AirlinesCheapest$48Average$74FlexibilityNo cancel feeOn-time65%
United AirlinesCheapest$59Average$186FlexibilityNo cancel feeOn-time69%
Alaska AirlinesCheapest$67Average$242FlexibilityNo cancel feeOn-time75%
SouthwestCheapest$97Average$269FlexibilityNo cancel feeOn-time63%
American AirlinesCheapest$222Average$366FlexibilityNo cancel feeOn-time71%

100% Free

Cheapflights is completely free to use, so you can start saving the moment you arrive.

Book with Flexibility

Our users can plan ahead with confidence and find flights with no change fees

Travel Smart

Millions of people come to us for their flight needs every year. We help make travel planning easy by providing useful insights and data-driven graphs that can inform your decisions.