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$177+ Cheap flights from Ontario to San Francisco (SFO)

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 9/5. Fares are subject to change and may not be available on all flights or dates of travel.
YYZ — SFO
Aug 24 — Aug 311
Mon 8/24
Mon 8/31
1 adult, Economy
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Cheap flight deals from Ontario to San Francisco

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 July 25, 2026.

This oojo deal was found by Cheapflights users on 7/22. 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 oojo is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 9/56:10 am
YXU
-
SFO
1 stop8h 50m
WestJet
Sat 9/121:00 pm
SFO
-
YXU
1 stop13h 20m
WestJet
Deal found 7/22$307
This oojo deal was found by Cheapflights users on 7/23. 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 oojo is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 10/86:10 am
YXU
-
SFO
1 stop8h 50m
WestJet
Tue 10/136:00 am
SFO
-
YXU
1 stop20h 20m
WestJet
Deal found 7/23$310
This FlightHub deal was found by Cheapflights users on 7/25. 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 FlightHub is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 9/252:50 pm
YYZ
-
SFO
1 stop10h 05m
Multiple Airlines
Wed 9/301:20 pm
SFO
-
YYZ
Nonstop5h 05m
Multiple Airlines
Deal found 7/25$318
This Mytrip deal was found by Cheapflights users on 7/25. 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 Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 9/109:45 am
YYZ
-
SFO
Nonstop5h 35m
Multiple Airlines
Mon 9/216:00 am
SFO
-
YYZ
1 stop8h 10m
Multiple Airlines
Deal found 7/25$319
This Kiwi.com deal was found by Cheapflights users on 7/25. 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.
Sun 9/610:50 am
YYZ
-
SFO
1 stop8h 50m
WestJet
Thu 9/106:00 am
SFO
-
YYZ
2 stops10h 55m
WestJet
Deal found 7/25$321
This WestJet deal was found by Cheapflights users on 7/22. 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 WestJet is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 9/106:10 am
YXU
-
SFO
1 stop8h 50m
WestJet
Mon 9/146:00 am
SFO
-
YXU
1 stop7h 45m
WestJet
Deal found 7/22$321
This Kiwi.com deal was found by Cheapflights users on 7/23. 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.
Sun 9/136:00 am
YYZ
-
SFO
1 stop9h 00m
WestJet
Tue 9/226:00 am
SFO
-
YYZ
2 stops10h 55m
WestJet
Deal found 7/23$322
This oojo deal was found by Cheapflights users on 7/23. 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 oojo is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 10/309:50 am
YYZ
-
SFO
Nonstop5h 55m
Porter Airlines
Thu 11/51:45 pm
SFO
-
YYZ
Nonstop4h 54m
Porter Airlines
Deal found 7/23$323
This Kiwi.com deal was found by Cheapflights users on 7/22. 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.
Sun 9/63:50 pm
YYZ
-
SFO
1 stop9h 05m
WestJet
Tue 9/81:00 pm
SFO
-
YYZ
2 stops13h 10m
WestJet
Deal found 7/22$324
This FlightHub deal was found by Cheapflights users on 7/22. 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 FlightHub is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 9/810:20 pm
YYZ
-
SFO
2 stops16h 40m
WestJet
Mon 9/141:00 pm
SFO
-
YYZ
2 stops13h 10m
WestJet
Deal found 7/22$325
This Kiwi.com deal was found by Cheapflights users on 7/22. 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 9/96:00 am
YYZ
-
SFO
1 stop9h 00m
WestJet
Sat 9/121:00 pm
SFO
-
YYZ
1 stop8h 10m
WestJet
Deal found 7/22$326
This oojo deal was found by Cheapflights users on 7/24. 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 oojo is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/148:40 pm
YKF
-
SFO
1 stop28h 15m
WestJet
Sun 10/186:00 am
SFO
-
YKF
1 stop10h 50m
WestJet
Deal found 7/24$327

Find flight deals from Ontario to San Francisco

Keep the following information in mind while searching for Ontario to San Francisco flight deals. Data was last updated July 25, 2026.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$307
(oojo)

One-way from

$177
(Mytrip)

Popular in

July

Cheapest in

November

Average price

$517

Good round-trip deal

$438 or less

Good one-way deal

$332 or less
Provider with most accurate pricing for Toronto (YTO)-San Francisco flight deals.
Search Deals
Provider most trusted by Cheapflights users for Toronto (YTO)-San Francisco flights.
Search Deals
From Ontario to San Francisco
Search Deals
One-way flight from Ontario to San Francisco
Search Deals
Highest demand for flights based on searches. 10% potential increase in price ($51 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 2% potential price decrease ($9 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in July 2026
Search Deals
Price to beat on a round-trip flight from Ontario to San Francisco.
Search Deals
Price to beat on a one-way flight from Ontario to San Francisco.
Search Deals

Cheapflights Fare Finder

 
Customize your flight search to find flights from Ontario to San Francisco 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 July 25, 2026.
Use the filters below to find and compare flights from Ontario to San Francisco that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

Cheapest round-trip

LondonSan Francisco

YXU - SFO

YXUSFO

London

Sat 9/5

6:10 am-12:00 pm

1 stop8h 50m

San Francisco

Sat 9/12

1:00 pm-5:20 am

1 stop13h 20m

$307

LondonSan Francisco

YXU - SFO

YXUSFO

London

Thu 9/10

6:10 am-12:00 pm

1 stop8h 50m

San Francisco

Mon 9/14

6:00 am-4:45 pm

1 stop7h 45m

$322

LondonSan Francisco

YXU - SFO

YXUSFO

London

Thu 9/10

3:30 pm-8:59 pm

1 stop8h 29m

San Francisco

Mon 9/14

6:40 am-9:40 pm

2 stops12h 00m

$337

TorontoSan Francisco

YKF - SFO

YKFSFO

Toronto Region of Waterloo Intl

Fri 9/18

8:40 pm-12:00 pm

1 stop18h 20m

San Francisco

Mon 9/28

6:00 am-7:50 pm

1 stop10h 50m

$352

TorontoSan Francisco

YKF - SFO

YKFSFO

Toronto Region of Waterloo Intl

Thu 9/17

8:40 pm-12:00 pm

1 stop18h 20m

San Francisco

Tue 9/22

6:00 am-7:50 pm

1 stop10h 50m

$359

TorontoSan Francisco

YKF - SFO

YKFSFO

Toronto Region of Waterloo Intl

Wed 9/9

8:40 pm-12:00 pm

1 stop18h 20m

San Francisco

Mon 9/21

6:00 am-7:50 pm

1 stop10h 50m

$367

TorontoSan Francisco

YKF - SFO

YKFSFO

Toronto Region of Waterloo Intl

Fri 9/11

8:40 pm-12:00 pm

1 stop18h 20m

San Francisco

Sun 9/20

6:00 am-7:50 pm

1 stop10h 50m

$372

HamiltonSan Francisco

YHM - SFO

YHMSFO

Hamilton

Wed 9/9

6:10 pm-9:55 pm

1 stop30h 45m

San Francisco

Mon 9/21

6:00 am-5:15 pm

1 stop8h 15m

$375

OttawaSan Francisco

YOW - SFO

YOWSFO

Ottawa

Tue 9/8

8:15 pm-9:55 pm

1 stop28h 40m

San Francisco

Tue 9/15

6:00 am-5:15 pm

1 stop8h 15m

$375

LondonSan Francisco

YXU - SFO

YXUSFO

London

Fri 10/9

3:30 pm-10:51 pm

2 stops10h 21m

San Francisco

Mon 10/12

10:51 pm-9:20 am

1 stop7h 29m

$412

Flights are sorted by cheapest round-trip flights first.

Deals found on 7/24

Showing 1-10 of 60 resultsSorted by cheapest first
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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.
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

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

Currently, January is the cheapest month in which you can book a flight from Region of Ontario to San Francisco (average of $357). Flying from Region of Ontario to San Francisco in July is currently the most expensive (average of $478). 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 ON 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 July 25, 2026.

Unlike in the afternoon, when flights are generally more expensive, you can save up to 45% on flights from Region of Ontario to San Francisco by exploring options for tickets in the morning.

Weekly flight availability from Region of 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 July 25, 2026.

The most flights from CAON to SFO are scheduled on a Saturday (24 on average). You will have fewer flight options on Wednesday, which is when the least amount of flights are scheduled (15 on average).

How much does it cost to fly round-trip from Region of Ontario to San Francisco?

Airfare is below average for this route at the moment.
Region of Ontario to San Francisco flights typically cost between $388 and $584 in August.
The cheapest round-trip price found within the last 5 days was $318 on WestJet (Aug 21-Aug 21).

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

Booking 79 days in advance of your planned departure date is, on average, the best time to get cheap flights from Region of Ontario to San Francisco. The general trend is that the closer you book to the departure date, the more expensive your flight will be.

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

Use this chart to determine the cheapest time to fly round-trip from Ontario to San Francisco. Price data was last updated on July 18, 2026.

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

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 airport do you fly into for flights to San Francisco from Ontario?

    If you book a flight to San Francisco from Ontario, you will be flying to San Francisco, which is the city’s only airport. San Francisco (SFO) is located 11.0 mi from the center of San Francisco.

  • How long is the flight from Region of Ontario to San Francisco?

    Departing from Region of Ontario to San Francisco will take you 7h 09m. Region of Ontario and San Francisco are separated by a distance of 2253 mi. Both multi-stop and nonstop flights can be found to your destination and back.

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

    To fly one-way, consider booking your trip with Porter Airlines, which is currently one of the cheapest options available, starting at $134. WestJet flights start at $148 while deals on Air Canada start at $175 one-way.

  • What are the most popular routes from Region of Ontario to San Francisco?

    While some choose either Montreal Pierre Elliott Trudeau Intl - San Francisco or Hamilton - San Francisco, Toronto Pearson Intl - San Francisco is the most popular route from Region of Ontario to San Francisco.

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

    Looking for the most reliable airlines to get you to your destination on time? Our data shows these are most likely to get you from Region of Ontario to San Francisco on time: Singapore Airlines (73%), American Airlines (69%), Porter Airlines (69%).

  • What are the cheapest flights from Region of Ontario to San Francisco?

    Looking at all options, your cheapest flight can be booked for $234. While the most popular route (Toronto Pearson Intl - San Francisco) can be booked for $267 on average, our data indicates $1,397 when flying from Region of Ontario to San Francisco.

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

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

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

    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.

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

    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.

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

    Currently, January is the cheapest month in which you can book a flight from Region of Ontario to San Francisco (average of $357). Flying from Region of Ontario to San Francisco in July is currently the most expensive (average of $478). 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

Traveling to a place near San Francisco?

Book flights to San Francisco if you plan to visit one of these locations
South San Francisco
Santa Clara
Santa Cruz
Fairfield
Roseville
Burlingame
Rancho Cordova
San Bruno
Cupertino
Emeryville
Newark
Watsonville
Hayward
Redwood City
San Carlos
San Ramon
Turlock
Vallejo
San Lorenzo
Davis

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.

Top 7 airlines flying from Ontario to San Francisco

Discover the top 7 airlines that operate flights from Ontario to San Francisco. 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 July 25, 2026.
AirlineCheapestAverageFlexibilityOn-time
WestJetCheapest$118Average$341FlexibilityNo cancel feeOn-time60%
DeltaCheapest$216Average$375FlexibilityNo cancel feeOn-timeN/A
Air CanadaCheapest$229Average$563FlexibilityNo cancel feeOn-time67%
Porter AirlinesCheapest$259Average$437FlexibilityNo cancel feeOn-time52%
United AirlinesCheapest$312Average$475FlexibilityNo cancel feeOn-time69%
American AirlinesCheapest$313Average$443FlexibilityNo cancel feeOn-time71%
Air TransatCheapest$324Average$458FlexibilityNo cancel feeOn-time50%

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