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Cheap Flights from Ontario Intl. Airport (ONT) to San Francisco (SFO)

View AU$132 flight on Sat, 24 Oct 2026Opens in a new window

Popular airlines from Ontario Intl. Airport (ONT) to San Francisco International Airport (SFO)

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Cheap Flights from Ontario Intl. Airport (ONT) to San Francisco (SFO)

Prices were available within the past 7 days for one-way flights and round trip tickets for the period specified. Prices and availability are subject to change. Additional terms apply.

United
Wed, 26 Aug - Wed, 2 Sept
ONT
Ontario
SFO
San Francisco
AU$271 Return, found 4 days ago
AU$271
Return
found 4 days ago
Select United flight, departing Wed, 26 Aug from Ontario to San Francisco, returning Wed, 2 Sept, priced at AU$271 found 4 days ago
United
Wed, 26 Aug - Wed, 2 Sept
ONT
Ontario
SFO
San Francisco
AU$321 Return, found 4 days ago
AU$321
Return
found 4 days ago
Select United flight, departing Wed, 26 Aug from Ontario to San Francisco, returning Wed, 2 Sept, priced at AU$321 found 4 days ago
United
Wed, 26 Aug - Wed, 2 Sept
ONT
Ontario
SFO
San Francisco
AU$371 Return, found 4 days ago
AU$371
Return
found 4 days ago
Select United flight, departing Wed, 26 Aug from Ontario to San Francisco, returning Wed, 2 Sept, priced at AU$371 found 4 days ago
United
Wed, 26 Aug - Wed, 2 Sept
ONT
Ontario
SFO
San Francisco
AU$375 Return, found 4 days ago
AU$375
Return
found 4 days ago
Select United flight, departing Wed, 26 Aug from Ontario to San Francisco, returning Wed, 2 Sept, priced at AU$375 found 4 days ago
American Airlines
Wed, 26 Aug - Wed, 2 Sept
ONT
Ontario
SFO
San Francisco
AU$388 Return, found 4 days ago
AU$388
Return
found 4 days ago
Select American Airlines flight, departing Wed, 26 Aug from Ontario to San Francisco, returning Wed, 2 Sept, priced at AU$388 found 4 days ago
United
Tue, 25 Aug - Tue, 1 Sept
ONT
Ontario
SFO
San Francisco
AU$412 Return, found 5 days ago
AU$412
Return
found 5 days ago
Select United flight, departing Tue, 25 Aug from Ontario to San Francisco, returning Tue, 1 Sept, priced at AU$412 found 5 days ago
United
Wed, 26 Aug - Wed, 2 Sept
ONT
Ontario
SFO
San Francisco
AU$426 Return, found 4 days ago
AU$426
Return
found 4 days ago
Select United flight, departing Wed, 26 Aug from Ontario to San Francisco, returning Wed, 2 Sept, priced at AU$426 found 4 days ago
United
Sun, 30 Aug - Sun, 6 Sept
ONT
Ontario
SFO
San Francisco
AU$436 Return, found 15 hours ago
AU$436
Return
found 15 hours ago
Select United flight, departing Sun, 30 Aug from Ontario to San Francisco, returning Sun, 6 Sept, priced at AU$436 found 15 hours ago
Alaska Airlines
Wed, 26 Aug - Wed, 2 Sept
ONT
Ontario
SFO
San Francisco
AU$448 Return, found 4 days ago
AU$448
Return
found 4 days ago
Select Alaska Airlines flight, departing Wed, 26 Aug from Ontario to San Francisco, returning Wed, 2 Sept, priced at AU$448 found 4 days ago
Delta
Wed, 26 Aug - Wed, 2 Sept
ONT
Ontario
SFO
San Francisco
AU$491 Return, found 4 days ago
AU$491
Return
found 4 days ago
Select Delta flight, departing Wed, 26 Aug from Ontario to San Francisco, returning Wed, 2 Sept, priced at AU$491 found 4 days ago

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

April is typically the cheapest month to fly

From AU$157 - AU$302 per traveller.

Frequently asked questions

How much does a flight from Ontario Intl. Airport (ONT) to San Francisco, CA (SFO-San Francisco Intl.) cost?
You can find one-way and return flights from ONT to SFO with Expedia. Flight prices vary based on the month and day of the week you want to travel, as well as the airline and how far in advance you book your ticket. Filter your search on Expedia by "Price (lowest to highest)" to see our cheapest fares first, and use the Price Tracking tool to receive alerts when ONT to SFO ticket fares go up or down.
What is the cheapest month to fly from Ontario Intl. Airport (ONT) to San Francisco, CA (SFO-San Francisco Intl.)?
April is typically the cheapest month to fly from Ontario Intl. Airport (ONT) to San Francisco, CA (SFO-San Francisco Intl.), with average return fares around AU$296. April often sees lower prices as it's just before the peak summer travel season, when demand tends to increase. Other cheap months to fly from Ontario Intl. Airport to San Francisco, CA include May and September.
Which airlines fly direct from Ontario Intl. Airport (ONT) to San Francisco, CA (SFO-San Francisco Intl.)?
You have 2 airlines offering direct flights from Ontario Intl. Airport (ONT) to San Francisco, CA (SFO-San Francisco Intl.). Here are the carriers:
  • United operates 34 direct flights from Ontario Intl. Airport (ONT) to San Francisco, CA (SFO-San Francisco Intl.) every week.
  • Frontier Airlines operates 10 direct flights from Ontario Intl. Airport (ONT) to San Francisco, CA (SFO-San Francisco Intl.) every week.
What is the cheapest airline that flies from Ontario Intl. Airport (ONT) to San Francisco, CA (SFO-San Francisco Intl.)?
Frontier Airlines is one of the cheapest airlines offering nonstop return flights from Ontario Intl. Airport (ONT) to San Francisco Intl. (SFO), with tickets starting from around AU$78 for flights that can be booked for departure within the next year. Southwest Airlines offers one of the cheapest connecting return flights from Ontario Intl. Airport (ONT) to San Francisco Intl. (SFO) with a layover in Harry Reid Intl. (LAS), starting from around AU$144. These prices are per adult, for economy/coach class. Use Expedia's search tool to compare the prices and schedules of airlines that fly this route to find the best option for your plans and budget.
How do I find cheap flights from Ontario Intl. Airport (ONT) to San Francisco, CA (SFO)?
To find a cheap flight from Ontario Intl. Airport (ONT) to San Francisco, CA (SFO), be flexible with your dates. Traveling outside of peak vacation months and booking a mid-week flight can help you save. Early morning and late night flights are often more affordable, too. Expedia allows you to compare flight times, airlines and routes all in one place to find low fares. You can also set up Price Tracking and receive alerts when fares go up or down.
What is the best airline to fly with from Ontario Intl. Airport (ONT) to San Francisco, CA (SFO-San Francisco Intl.)?
The best airline to fly with from Ontario Intl. Airport (ONT) to San Francisco, CA (SFO-San Francisco Intl.) will differ from traveler to traveler. If you like to fly early, United offers early morning flights. If price is the most important factor, Frontier Airlines typically offers the lowest fares. Southwest Airlines offers the most daily flights from Ontario Intl. Airport (ONT) to San Francisco, CA (SFO-San Francisco Intl.), which is great if flexibility is what you value most. The best carrier for this journey could also be the one you have a loyalty membership with, as flying with that airline or another airline within the same alliance could help you collect points or enjoy lounge access.
What is the best time to fly from Ontario Intl. Airport (ONT) to San Francisco, CA (SFO-San Francisco Intl.)?
The cheapest months to fly from Ontario Intl. Airport (ONT) to San Francisco, CA (SFO-San Francisco Intl.) are typically April and May, with average return flights costing around AU$296. However, the most popular months for this route are July and March, which means you'll find plenty of flight options during those times. If you're looking for the best balance of good value and a wide selection of flights, you might consider March or April, as they offer a good compromise between price and availability.
How many flights per day from Ontario Intl. Airport (ONT) to San Francisco, CA (SFO-San Francisco Intl.)?
You'll find approximately 6 nonstop flights per day from Ontario Intl. Airport (ONT) to San Francisco, CA (SFO-San Francisco Intl.). For even more choices, look at flights that include layovers, as there are around 56 connecting flights per day. Some common connection points include Harry Reid Intl. (LAS), Seattle - Tacoma Intl. (SEA), and Sky Harbor Intl. (PHX).
What is the earliest flight from Ontario Intl. Airport (ONT) to San Francisco, CA (SFO-San Francisco Intl.)?
The earliest flight from Ontario Intl. Airport (ONT) to San Francisco, CA (SFO-San Francisco Intl.) typically departs around 12:55 AM local time. This flight is operated by American Airlines. This is a seasonal service, active only in September. An early departure like this can help you make the most of your time at your destination. To compare early flights on Expedia, select the "Early Morning" and "Morning" filters in your search.
What day of the week has the most flights from Ontario Intl. Airport (ONT) to San Francisco, CA (SFO-San Francisco Intl.)?
You'll typically find the most flights from Ontario Intl. Airport (ONT) to San Francisco, CA (SFO-San Francisco Intl.) on a Friday, with around 45 flights available. This gives you a good selection of options for your journey. Major airlines on this route include Southwest Airlines, Alaska Airlines, and Delta.
What are the most popular departure times for flights from Ontario Intl. Airport (ONT) to San Francisco, CA (SFO-San Francisco Intl.)?
The most popular departure times for flights from Ontario Intl. Airport (ONT) to San Francisco, CA (SFO-San Francisco Intl.) are in the morning, from 6am to 9am. Many major carriers, including Alaska Airlines, Frontier Airlines and Southwest Airlines, offer flights during this window. Many travellers prefer these times as it allows for an early start to their day in San Francisco.
How long does it take to fly from Ontario Intl. Airport (ONT) to San Francisco, CA (SFO-San Francisco Intl.)?
A nonstop flight from Ontario Intl. Airport (ONT) to San Francisco, CA (SFO-San Francisco Intl.) typically takes around 1 hour 30 minutes. This route covers a distance of approximately 586 kilometres. If you opt for a one-stop flight, your travel time will be significantly longer, usually around 9 hours. Flights with two or more stops generally take about 8 hours 30 minutes. Keep in mind that actual flight times can vary due to factors like wind patterns and air traffic, so it's always a good idea to allow for some extra time when planning your trip.
Can you fly business or first class from Ontario Intl. Airport (ONT) to San Francisco, CA (SFO-San Francisco Intl.)?
Yes, you can fly business class or first class between ONT and SFO. You can fly business class with Frontier Airlines and Delta.First class cabins are available on Alaska Airlines, United, Delta, and American Airlines.
How do I earn miles on a Ontario Intl. Airport (ONT) to San Francisco, CA (SFO) flight with Expedia?
It's easy to earn miles on a Ontario Intl. Airport (ONT) to San Francisco, CA (SFO) flight when you book with Expedia. Before you confirm your booking, simply select your frequent flyer program and enter your program number. As a member of One Key™, you can also earn OneKeyCash™* on top of your airline miles when you book with Expedia.*Excludes taxes and fees. OneKeyCash is not redeemable for cash and can only be used on Expedia and other participating brands.
What airports do you fly into for San Francisco, CA (SFO) from Ontario Intl. Airport (ONT)?
If you're planning to travel to San Francisco from Los Angeles - Ontario Intl. (ONT), you can fly directly into San Francisco Intl. (SFO). Some flights may connect through major hubs like Sonoma County (STS), Portland Intl. (PDX), or Harry Reid International Airport (LAS) before reaching San Francisco. Compare routes and airports on Expedia to find the best flight options for your travel plans.
Is it cheaper to buy a plane ticket from Ontario Intl. Airport (ONT) to San Francisco, CA (SFO) at the last minute?
Typically, booking a last minute flight from Ontario Intl. Airport (ONT) to San Francisco, CA (SFO) will be more expensive than booking in advance. As the departure date approaches, there are usually fewer seats available which can drive up the cost. However, if there's some wiggle room with your travel dates and times, you could bag a cheap last-minute fare.
Is it cheaper to book a Ontario Intl. Airport (ONT) to San Francisco, CA (SFO) flight and hotel package?
Securing a Ontario Intl. Airport (ONT) to San Francisco, CA (SFO) flight and hotel package is usually cheaper than booking separately. With Expedia, you can enjoy the ease of organizing your travels all in one place. Select from our extensive range of stays and then add flights, activities and car rentals to your booking. Bundle everything together, and you could save hundreds of dollars.
Can I cancel or change the date of my flight from Ontario Intl. Airport (ONT) to San Francisco, CA (SFO)?
If you booked your Ontario Intl. Airport (ONT) to San Francisco, CA (SFO) flight within the last 24 hours, you may be able to modify or cancel it without any fees. Depending on the airline and the type of ticket you have, additional charges may apply for changes beyond this timeframe. Airline policies and contact information can be found in your itinerary or confirmation email. Or, head to our Customer Service portal if you'd like more information.

Travel information

Origin airport
Ontario Intl. Airport
Destination airport
San Francisco Intl.
Airlines serving
United
Return price
AU$270
Distance
582 km
Average flight time
1 hour 28 mins

Book with confidence

Your quick guide to flights from Ontario Intl. Airport to San Francisco

Pick up great flights from Ontario Intl. Airport to San Francisco

With Expedia, you have your pick of flights a day with 20 airlines covering flights from Ontario Intl. Airport to San Francisco. Whether you’re on a business trip, a family holiday or a luxury break, just enter your travel dates, hit search then check out your choice of flights. Select from return, one way or multi-city flights, and use the advance search tool if you want a direct or refundable flight. You can narrow your search to show you just your preferred cabin class and airline, too. It’s all easy. You can book direct flights from Ontario Intl. Airport to San Francisco that take around hours.

Find cheap flights from Ontario Intl. Airport to San Francisco

From the great flight deals with prices currently ranging from AU$271 to AU$491, you can choose to see the cheapest flights first. Generally, you can book the cheapest flights from Ontario Intl. Airport to San Francisco around 4 to 6 weeks in advance. If your travel dates are flexible, try to avoid weekends and peak seasons – when you are more likely to grab the lowest prices. Even last minute, there are some impressive deals. The cheapest time to fly to San Francisco is normally in August.

Reasons to book your flight from Ontario Intl. Airport to San Francisco with Expedia

Expedia makes it easy to find, book, and travel, with everything you need all in one place. When you enter your travel details, find fantastic deals just for you on flight tickets from Ontario Intl. Airport to San Francisco across all the main airline carriers, so you can save time, dollars, and hassle finding the perfect flight. If you think your plans could change, choose refundable flights so any changes won’t cost you more. Book your flight to San Francisco right now and, if you join Expedia Rewards, you earn points this time and every time you travel with Expedia.

Your quick guide to flights from Ontario Intl. Airport to San Francisco

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*Available to Expedia members.