$29 Cheap Flights from Ontario (ONT) to San Francisco (SFO)

View $29 flight on Mon, Aug 11, 2025Opens in a new window

Popular airlines from Los Angeles - Ontario Intl. Airport (ONT) to San Francisco Intl. Airport (SFO)

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Cheap Flights from Ontario to San Francisco (ONT-SFO)

Prices were available within the past 7 days and start at $29 for one-way flights and $84 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

United
Wed, Aug 6 - Tue, Aug 12
ONT
Ontario
SFO
San Francisco
$84 Roundtrip, just found
$84
Roundtrip
just found
Select United flight, departing Wed, Aug 6 from Ontario to San Francisco, returning Tue, Aug 12, priced at $84 just found
Frontier Airlines
Fri, Aug 8 - Sun, Aug 10
ONT
Ontario
SFO
San Francisco
$88 Roundtrip, just found
$88
Roundtrip
just found
Select Frontier Airlines flight, departing Fri, Aug 8 from Ontario to San Francisco, returning Sun, Aug 10, priced at $88 just found
United
Fri, Aug 8 - Sun, Aug 10
ONT
Ontario
SFO
San Francisco
$90 Roundtrip, just found
$90
Roundtrip
just found
Select United flight, departing Fri, Aug 8 from Ontario to San Francisco, returning Sun, Aug 10, priced at $90 just found
Frontier Airlines
Mon, Aug 4 - Wed, Aug 6
ONT
Ontario
SFO
San Francisco
$93 Roundtrip, just found
$93
Roundtrip
just found
Select Frontier Airlines flight, departing Mon, Aug 4 from Ontario to San Francisco, returning Wed, Aug 6, priced at $93 just found
United
Tue, Aug 5 - Tue, Aug 12
ONT
Ontario
SFO
San Francisco
$94 Roundtrip, just found
$94
Roundtrip
just found
Select United flight, departing Tue, Aug 5 from Ontario to San Francisco, returning Tue, Aug 12, priced at $94 just found
United
Tue, Jul 29 - Tue, Aug 5
ONT
Ontario
SFO
San Francisco
$96 Roundtrip, just found
$96
Roundtrip
just found
Select United flight, departing Tue, Jul 29 from Ontario to San Francisco, returning Tue, Aug 5, priced at $96 just found
United
Mon, Aug 11 - Thu, Aug 14
ONT
Ontario
SFO
San Francisco
$97 Roundtrip, just found
$97
Roundtrip
just found
Select United flight, departing Mon, Aug 11 from Ontario to San Francisco, returning Thu, Aug 14, priced at $97 just found
Southwest Airlines
Sat, Aug 9 - Sun, Aug 10
ONT
Ontario
SFO
San Francisco
$109 Roundtrip, just found
$109
Roundtrip
just found
Select Southwest Airlines flight, departing Sat, Aug 9 from Ontario to San Francisco, returning Sun, Aug 10, priced at $109 just found
American Airlines
Thu, Sep 11 - Mon, Sep 15
ONT
Ontario
SFO
San Francisco
$187 Roundtrip, just found
$187
Roundtrip
just found
Select American Airlines flight, departing Thu, Sep 11 from Ontario to San Francisco, returning Mon, Sep 15, priced at $187 just found
Alaska Airlines
Wed, Oct 8 - Wed, Oct 15
ONT
Ontario
SFO
San Francisco
$282 Roundtrip, just found
$282
Roundtrip
just found
Select Alaska Airlines flight, departing Wed, Oct 8 from Ontario to San Francisco, returning Wed, Oct 15, priced at $282 just found

Find the cheapest month to fly from Ontario (ONT) to San Francisco (SFO)

August is typically the cheapest month to fly

From $48 - $126 per traveler.

Graph displaying average flight prices per month

Alternative airports near San Francisco

Prices were available within the past 7 days. Prices and availability are subject to change.

Select flight to Norman Y. Mineta San Jose Intl. SJC. Average driving time to city center is 50 minutes. Flights from $218
SJC
Norman Y. Mineta San Jose Intl.
Average driving time to city center50 min
Flights from $218
Select flight to Oakland Intl. OAK. Average driving time to city center is 26 minutes. Flights from $218
OAK
Oakland Intl.
Average driving time to city center26 min
Flights from $218
Flights from Ontario (ONT) to San Francisco (SFO)
Origin airport
Los Angeles - Ontario Intl.
Destination airport
San Francisco Intl.
Airlines serving
Alaska Airlines, American Airlines, Delta, Frontier Airlines, JetBlue Airways, Southwest Airlines, United
Roundtrip price
$78
Distance
363 mi
Average flight time
1 hour 48 mins

Ontario to San Francisco Flights

The cheapest times to fly from Ontario to San Francisco

On average, Thursday can be the cheapest time to fly, according to data from the Airlines Reporting Corporation (ARC), one of the world's biggest databases for global airline sales. The data reveals that you could save up to 16% by flying on a Thursday—the cheapest day to travel on average—instead of a Sunday—the most expensive. Some of the most affordable flights from Ontario to San Francisco are during the month of August. You can find some of the cheapest flights from Ontario to San Francisco with Expedia's search tool and vast selection of airlines.

 

The best time to book a flight from Ontario to San Francisco

Sunday is one of the best days to book for cheap flights from Ontario to San Francisco: Tickets reserved on a Sunday cost between 6% and 13% less than those reserved on a Friday, according to ARC data. The data also suggests booking early can also lead to cheaper airfares. You could save 24% by buying your tickets for domestic flights at least a month in advance and 10% by booking international flights 2 months in advance.

 

How to find cheap round-trip tickets from Ontario to San Francisco

Being flexible with your dates and using Expedia's Price Drop Protection and Price Tracking features are some of the best ways of finding a cheap ticket from Ontario to San Francisco in 2025. You can also book with separate airlines for your outbound and return journeys, from $29 one-way. Expedia also offers Price Drop Protection, so if the cost of your airfare goes down after booking, you'll receive a credit for the difference*. This is available for a small fee, and is free to One Key Gold and Platinum tier members.

 

Expedia's Price Tracking feature means you can stay on top of airfares without manually checking every day. It sends you automated price alerts for cheap Ontario to San Francisco flights and uses historical data to indicate when the best time to book is. Download Expedia's free app to activate this handy tool in a few easy taps.

 

You could also save big by booking one of Expedia's vacation packages. Bundling together your Ontario to San Francisco airfare with your accommodations and car rental is often cheaper than booking everything separately. There’s also One Key, Expedia's generous rewards program. Join for free and you could earn One Key cash on most bookings to save on future adventures.

 

*Terms apply.

 

Disclaimer: ARC The statistics are based on average round-trip ticket prices between January and August 2023. The percentages you see are averages.

 

Frequently asked questions

How much does a flight from Los Angeles - Ontario Intl. Airport (ONT) to San Francisco Intl. Airport (SFO) cost?
Cheap return flights from Los Angeles - Ontario Intl. Airport (ONT) to San Francisco Intl. Airport (SFO) start at $52. This information is based on the cheapest price found on Expedia for this return journey departing within the next three months. This airfare is for a United flight leaving ONT on August 6 2025 and touching down at SFO. The price was last updated on July 12 2025 and has not changed since.
What is the cheapest month to fly from ONT to SFO?
The cheapest flights from ONT to SFO are usually during off-peak season, when demand is lower. To save money, avoid flying during public holidays, school breaks and major local events.
Which airlines fly direct from Los Angeles - Ontario Intl. Airport (ONT) to San Francisco Intl. Airport (SFO)?
Hop on a nonstop flight with United Airlines and head straight from Los Angeles - Ontario Intl. Airport (ONT) to San Francisco Intl. Airport (SFO).
What is the cheapest airline that flies from ONT to SFO?
Currently, the cheapest carrier offering one-way flights from ONT to SFO is United. You can book a seat on this route from $29. This fare is based on the lowest price found on Expedia departing within the next three months. The flight takes off from ONT on August 12 2025. Prices were last updated on July 12 2025 and have not changed since.
How many flights per day from Los Angeles - Ontario Intl. Airport (ONT) to San Francisco Intl. Airport (SFO)?
With an average of 3 nonstop flights that operate from Los Angeles - Ontario Intl. Airport (ONT) to San Francisco Intl. Airport (SFO) daily, you'll be cruising above the clouds before you know it.
What are the most popular departure times for flights from Los Angeles - Ontario Intl. Airport (ONT) to San Francisco Intl. Airport (SFO)?
The 10 AM departures from ONT to SFO are the most sought after. Prices can be higher for these popular slots. If you're looking to save, choose a less crowded time to fly.
What day of the week has the most flights from ONT to SFO?
If you fly on a Friday, you'll get the biggest range of options for flights from Los Angeles - Ontario Intl. Airport (ONT) to San Francisco Intl. Airport (SFO).
What is the earliest flight from Los Angeles - Ontario Intl. Airport (ONT) to San Francisco Intl. Airport (SFO)?
Los Angeles - Ontario Intl. Airport (ONT)'s first flight to San Francisco Intl. Airport (SFO) leaves at approximately 6:00AM UTC-8. With a travel time of 1h 35m, you'll land at around 7:35AM UTC-8.
How long does it take to fly from Los Angeles - Ontario Intl. Airport (ONT) to San Francisco Intl. Airport (SFO)?
Flights from ONT to SFO have an average travel time of 1 hour and 33 minutes. The total distance between the two airports is 360 mi.
What airline has the least delays from ONT to SFO?
Consider traveling with Frontier Airlines if you'd like to fly straight from Los Angeles - Ontario Intl. Airport (ONT) to San Francisco Intl. Airport (SFO) without any delays. This airline has the strongest track record for punctuality, with an on-time score of 84%. Want to be notified if anything changes? You can check your flight status using the Expedia App.
What is the best time to fly from Los Angeles - Ontario Intl. Airport (ONT) to San Francisco Intl. Airport (SFO)?
Opt for a flight from Los Angeles - Ontario Intl. Airport (ONT) to San Francisco Intl. Airport (SFO) that leaves before 3 PM to reduce the risk of cancellations and delays. Departures later than this have a 22% higher chance of being canceled, on average.**Most reliable time of the day and month to travel recommendation is based on January through August 2024 flight status data sourced from OAG's global flight data platform.
What airports do you fly into for San Francisco from Los Angeles - Ontario Intl. Airport (ONT)?
Los Angeles - Ontario Intl. Airport (ONT) offers direct flights to San Francisco. These are a few of the airports you can fly to without detours:

  • San Francisco Intl. Airport (SFO)
  • Norman Y. Mineta San Jose Intl. Airport (SJC)
  • Oakland Intl. Airport (OAK)

Is it cheaper to buy a plane ticket from Los Angeles - Ontario Intl. Airport (ONT) to San Francisco Intl. Airport (SFO) last-minute?
Holding off until right before your break to book a ticket from ONT to SFO often results in higher prices. While it's possible to find some last-minute deals, they aren't always guaranteed. Be flexible with your itinerary for a better chance of getting a bargain.
Is it cheaper to book an ONT to SFO flight and hotel package?
Compared with arranging flights and hotels separately, booking an ONT to SFO flight and hotel package with Expedia could result in significant savings. Better still, having it all in one place will take the stress out of travel planning. Just pick your flights and select from our wide range of hotels, then customize your trip with extras like tours and car rentals.
Can I cancel or change the date of my flight from Los Angeles - Ontario Intl. Airport (ONT) to San Francisco Intl. Airport (SFO)?
If you booked your ONT to SFO flight in the last 24 hours, you may be able to cancel or modify it at no cost. Depending on the airline and the ticket type you purchased, additional charges may apply for changes after that time. Airline policies and contact information can be found in your itinerary or confirmation email. Or, visit our Customer Service portal if you'd like more information.

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