Question 1

How popular is this Ontario to San Francisco flight route?

Accepted Answer

Within the past month, 24 users have taken a look at flights from Ontario to San Francisco.

Question 2

What are the cheapest airlines flying from Ontario to San Francisco round-trip?

Accepted Answer

Our cheapest airline available from Ontario to San Francisco is Frontier. Our recent data shows that you can find tickets from as low as C$ 103 on this airline. Additional options worth looking into are United Airlines and Southwest, starting at C$ 133 and C$ 239 round-trip. You may be able to fly from Ontario to San Francisco for 35% less than the average price by searching for these airlines.

Question 3

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

Accepted Answer

The cheapest airlines for a one-way flight from Ontario to San Francisco are United Airlines (C$ 67), Frontier (C$ 92), and Southwest (C$ 104).

Question 4

How far ahead should I book a flight from Ontario to San Francisco?

Accepted Answer

To ensure you get the cheapest price possible for a flight from Ontario to San Francisco, you should look to book at least 89 days in advance of your intended travel date. The price of your flight may increase if you delay and leave booking until a week or so before departure.

Question 5

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

Accepted Answer

Currently, January is the cheapest month in which you can book a flight from Ontario to San Francisco (average of C$ 276). Flying from Ontario to San Francisco in December is currently the most expensive (average of C$ 368). 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.

Question 6

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

Accepted Answer

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

Question 7

Weekly flight availability from Ontario to San Francisco

Accepted Answer

The most flights from ONT to SFO are scheduled on a Monday (9 on average). You will have fewer flight options on Wednesday, which is when the least amount of flights are scheduled (3 on average).

Question 8

E

Accepted Answer

In terms of precipitation, rainfall in San Francisco ranges from 0.0 - 112.0 mm per month. January is typically the wettest month, when rainfall can reach 112.0 mm. July is typically the driest time to visit San Francisco when rainfall is around 0.0 mm.

Question 9

E

Accepted Answer

If weather is an important factor for your trip to San Francisco, 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 17.0 C. Travellers hoping to avoid the cold should look outside of January, when temperatures are typically at their lowest (around 11.0 C).

Question 10

What are the cheapest flights from Ontario to San Francisco?

Accepted Answer

While on average a flight from Ontario to San Francisco is generally C$ 2,220, our data shows the cheapest flight currently is C$ 188. When looking at the most popular route, (Ontario - San Francisco), you can expect to pay C$ 235 for that flight.

Question 11

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

Accepted Answer

No one likes to see their flight delayed. When booking a flight from Ontario to San Francisco consider choosing Emirates (91%), SkyWest Airlines (89%) or Copa Airlines (88%) as they are the most reliable in getting you off to your destination on time.

Question 12

What is the cheapest day to fly round-trip from Ontario to San Francisco?

Accepted Answer

Departing on a Thursday is a good option for securing a great price. You can expect to save up to 504% when planning your travel around this day of the week.

Question 13

How far in advance should I book a flight from Ontario to San Francisco?

Accepted Answer

Users have found that booking a flight from Ontario to San Francisco at least 36 days early can save you up to 87% on average compared to booking a flight this week. If booking 36 days before your flight isn’t an option for you, users have found flights from Ontario to San Francisco for as little as C$ 195 when booking for a departure date within the next two weeks. You can also check prices now. Some users have found airline tickets as low as C$ 266 for flights departing within the next 3 days.

Question 14

What is the cheapest month to fly from Ontario to San Francisco?

Accepted Answer

October can be a great time to fly to San Francisco from Ontario with a flight ticket averaging about C$ 198. Cheapflights users have found deals in the month of October for as cheap as C$ 47. The most expensive prices can be found in the month of May.

Question 15

What is the cheapest time of day to fly from ONT to SFO?

Accepted Answer

It’s typically best to fly out from Ontario to San Francisco at noon. Doing so could potentially save you 22% on the flight price compared to flying in the afternoon, which is usually more expensive.

Question 16

What airports do I use to fly from Ontario to San Francisco?

Accepted Answer

Booking a flight from Ontario (ONT) to San Francisco (SFO) is your only option if you wish to fly from Ontario to San Francisco. On a typical day, there are 6 flights from Ontario to San Francisco, all of which are around 1h 32m for a nonstop flight. You can also purchase a plane ticket from 1 airline when you book a flight from Ontario to San Francisco.

Question 17

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

Accepted Answer

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

Question 18

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

Accepted Answer

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.

Question 19

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

Accepted Answer

Yes. Cheapflights offers flight deals from Ontario to San Francisco by cabin class. In addition to browsing deals, you can also filter by cabin class on the search results page after making a search.

Question 20

How does Cheapflights help users find flights from Ontario to San Francisco?

Accepted Answer

Cheapflights makes it easy to find Ontario to San Francisco flights by helping our users search from 900+ travel sites for deals. We also provide you with filters for cabin, price, airline, airports, number of stops, and many more to narrow down that perfect flight.

Question 21

Why should you use Cheapflights to find cheap flight tickets from Ontario to San Francisco?

Accepted Answer

Millions of users choose and trust Cheapflights to book the best flight deals from Ontario to San Francisco for free. We help you search and compare prices from hundreds of airlines for the right flight just for you.

Question 22

Can Cheapflights find flights from Ontario to San Francisco with no change fees?

Accepted Answer

Users can book flights with no change fees policies with our dedicated filters. Book flights from Ontario to San Francisco flexibly with Cheapflights today.

Question 23

Can Cheapflights notify me if prices for flights from Ontario to San Francisco become cheaper?

Accepted Answer

Not ready to book yet? You can track prices for flights from Ontario to San Francisco on Cheapflights with our Price Alert feature and get notified when better prices are available.

Round-trip from	C$ 103
One-way from	C$ 67
Popular in	November
Cheapest in	May
Average price	C$ 185
Good round-trip deal	C$ 188 or less

Cheap flights from Ontario to San Francisco from C$ 67

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 10/9. Fares are subject to change and may not be available on all flights or dates of travel.

Cheapflights Tip: The best prices from Ontario to San Francisco are usually found in May or September, booked 89 days in advance, depart on a Friday or Tuesday and return on a Monday

Cheap flight deals from Ontario to San Francisco

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Find flight deals from Ontario to San Francisco

Cheapest flights from Ontario to San FranciscoExplore the most affordable flight options available from Ontario to San Francisco. Find the lowest fares from popular airlines and budget airlines, with prices last updated on 29 July 2025.

Explore the most affordable flight options available from Ontario to San Francisco. Find the lowest fares from popular airlines and budget airlines, with prices last updated on 29 July 2025.

Cheapflights Fare Finder

Use the filters below to find and compare flights from Ontario to San Francisco that are best for you.

Best time to book a flight from Ontario to San Francisco

Have a flexible travel schedule? Discover the best time to fly to San Francisco from Ontario with our price prediction graph.

Cheapflights Insights

Everything you need to know about your flight from Ontario to San Francisco

How far ahead should I book a flight from Ontario to San Francisco?

Use this chart to determine the optimal time to book a round-trip flight from Ontario to San Francisco. Price data was last updated on 25 July 2025.

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

What is the cheapest time of day to fly from ONT to SFO?

Find hourly flight availability from Ontario to San Francisco. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated 29 July 2025.

Weekly flight availability from Ontario to San Francisco

Explore weekly flight availability from Ontario to San Francisco. 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 29 July 2025.

Reviews of airlines servicing San Francisco

Read reviews from past customers who have flown Alaska Airlines,Southwest, andUnited Airlines from Ontario to San Francisco. Users can see the overall rating for each airline as well as how each is rated in terms of entertainment options, comfort, food, crew/service, and boarding process.

Related info for your journey

Find useful and relevant information for your journey from Ontario to San Francisco. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.

What airports do I use to fly from Ontario to San Francisco?

How popular is this Ontario to San Francisco flight route?

What are the cheapest airlines flying from Ontario to San Francisco round-trip?

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

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

What are the cheapest flights from Ontario to San Francisco?

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

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

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

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

Travelling to a place near San Francisco?

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Alternative routes for Ontario to San Francisco

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Top airline flying from Ontario to San Francisco

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How does Cheapflights help users find flights from Ontario to San Francisco?

Why should you use Cheapflights to find cheap flight tickets from Ontario to San Francisco?

Can Cheapflights find flights from Ontario to San Francisco with no change fees?

Can Cheapflights notify me if prices for flights from Ontario to San Francisco become cheaper?

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Cheapest flights from Ontario to San Francisco
Explore the most affordable flight options available from Ontario to San Francisco. Find the lowest fares from popular airlines and budget airlines, with prices last updated on 29 July 2025.