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$141+ 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 7/25. Fares are subject to change and may not be available on all flights or dates of travel.
YYZ — SFO
jun. 17 — jun. 241
mar. 6/17
mar. 6/24
1 adult, Economy
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Cheap 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 junio 12, 2025.

Round-trip from

$236
(Trip.com)

One-way from

$141
(SmartFares)

Popular in

December

Cheapest in

April

Average price

$377

Good round-trip deal

$348 or less

Good one-way deal

$203 or less
From Ontario to San Francisco
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One-way flight from Ontario to San Francisco
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Highest demand for flights based on searches. 5% potential increase in price ($20 potential increase over avg. RT price).
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Cheapest flight prices on average. 2% potential price decrease ($10 potential savings vs. average RT price).
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Average for round-trip flights in June 2025
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Price to beat on a round-trip flight from Ontario to San Francisco.
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Price to beat on a one-way flight from Ontario to San Francisco.
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Find 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 junio 12, 2025.

This Trip.com deal was found by Cheapflights users on 6/10. 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 Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
lun. 8/116:00 amYHM - SFO
1 stop8h 56mWestJet
mié. 8/1312:50 pmSFO - YHM
1 stop8h 51mWestJet
Deal found 6/10$236
This FlightHub deal was found by Cheapflights users on 6/12. 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.
jue. 7/247:15 pmYOW - SFO
2 stops21h 44mWestJet
dom. 8/36:05 pmSFO - YOW
1 stop9h 40mWestJet
Deal found 6/12$262
This Air Canada deal was found by Cheapflights users on 6/11. 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 Air Canada is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
vie. 9/263:35 pmYXU - SFO
1 stop8h 18mAir Canada
mar. 10/2810:45 pmSFO - YXU
1 stop7h 20mAir Canada
Deal found 6/11$263
This Trip.com deal was found by Cheapflights users on 6/11. 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 Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
dom. 6/298:00 pmYXU - SFO
1 stop19h 05mWestJet
sáb. 7/52:45 pmSFO - YXU
2 stops11h 29mWestJet
Deal found 6/11$278
This American Airlines deal was found by Cheapflights users on 6/12. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
jue. 6/2611:40 amYYZ - SFO
1 stop12h 47mAmerican Airlines
sáb. 7/55:41 amSFO - YYZ
1 stop14h 14mAmerican Airlines
Deal found 6/12$284
This Trip.com deal was found by Cheapflights users on 6/10. 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 Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
lun. 8/255:30 pmYUL - SFO
1 stop21h 26mWestJet
mar. 9/212:50 pmSFO - YUL
1 stop8h 51mWestJet
Deal found 6/10$285
This FlightHub deal was found by Cheapflights users on 6/10. 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.
dom. 9/216:30 amYYZ - SFO
1 stop10h 27mWestJet
mar. 10/77:30 amSFO - YYZ
1 stop8h 22mWestJet
Deal found 6/10$285
This FlightHub deal was found by Cheapflights users on 6/10. 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.
jue. 7/247:45 pmYKF - SFO
2 stops21h 14mWestJet
dom. 8/37:30 amSFO - YKF
1 stop14h 16mWestJet
Deal found 6/10$286
This Kiwi.com deal was found by Cheapflights users on 6/11. 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.
sáb. 9/279:45 amYYZ - SFO
Nonstop5h 38mMultiple Airlines
sáb. 10/257:30 amSFO - YYZ
1 stop8h 22mMultiple Airlines
Deal found 6/11$291
This FlightHub deal was found by Cheapflights users on 6/9. 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.
vie. 6/206:45 amYUL - SFO
1 stop8h 40mPorter Airlines
mié. 6/251:25 pmSFO - YUL
1 stop8h 12mPorter Airlines
Deal found 6/9$297
This Air Canada deal was found by Cheapflights users on 6/10. 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 Air Canada is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
sáb. 11/223:25 pmYTZ - SFO
1 stop9h 12mAir Canada
mié. 12/38:40 amSFO - YTZ
1 stop10h 10mAir Canada
Deal found 6/10$300
This Mytrip deal was found by Cheapflights users on 6/11. 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.
mié. 7/98:25 pmYKF - SFO
1 stop16h 05mFlair Airlines
mié. 7/1610:15 amSFO - YKF
1 stop17h 55mFlair Airlines
Deal found 6/11$304

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 junio 12, 2025.
Use the filters below to find and compare flights from Ontario to San Francisco that are best for you.

Fly from

Ontario

Fly to

San Francisco

Route

Depart

Return

Price

HamiltonSan Francisco

YHM - SFO

YHMSFO

Hamilton

lun. 8/11

6:00 am-11:56 am

1 stop8h 56m

San Francisco

mié. 8/13

12:50 pm-12:41 am

1 stop8h 51m

$236

OttawaSan Francisco

YOW - SFO

YOWSFO

Ottawa

jue. 7/24

7:15 pm-1:59 pm

2 stops21h 44m

San Francisco

dom. 8/3

6:05 pm-6:45 am

1 stop9h 40m

$262

LondonSan Francisco

YXU - SFO

YXUSFO

London

vie. 9/26

3:35 pm-8:53 pm

1 stop8h 18m

San Francisco

mar. 10/28

10:45 pm-9:05 am

1 stop7h 20m

$263

LondonSan Francisco

YXU - SFO

YXUSFO

London

dom. 6/29

8:00 pm-12:05 pm

1 stop19h 05m

San Francisco

sáb. 7/5

2:45 pm-5:14 am

2 stops11h 29m

$278

MontrealSan Francisco

YUL - SFO

YULSFO

Montreal Pierre Elliott Trudeau Intl

lun. 8/25

5:30 pm-11:56 am

1 stop21h 26m

San Francisco

mar. 9/2

12:50 pm-12:41 am

1 stop8h 51m

$285

TorontoSan Francisco

YYZ - SFO

YYZSFO

Toronto Pearson Intl

jue. 7/24

10:25 pm-1:59 pm

2 stops18h 34m

San Francisco

dom. 8/3

7:30 am-12:33 am

2 stops14h 03m

$285

TorontoSan Francisco

YKF - SFO

YKFSFO

Toronto Region of Waterloo Intl

jue. 7/24

7:45 pm-1:59 pm

2 stops21h 14m

San Francisco

dom. 8/3

7:30 am-12:46 am

1 stop14h 16m

$286

TorontoSan Francisco

YYZ - SFO

YYZSFO

Toronto Pearson Intl

jue. 6/26

6:49 am-6:49 pm

1 stop15h 00m

San Francisco

mar. 7/15

6:45 pm-11:12 am

2 stops13h 27m

$288

TorontoSan Francisco

YYZ - SFO

YYZSFO

Toronto Pearson Intl

mié. 6/25

9:45 am-12:25 pm

Nonstop5h 40m

San Francisco

dom. 7/6

6:05 pm-12:33 am

2 stops27h 28m

$291

MontrealSan Francisco

YUL - SFO

YULSFO

Montreal Pierre Elliott Trudeau Intl

lun. 8/18

6:45 am-12:23 pm

1 stop8h 38m

San Francisco

lun. 8/25

1:25 pm-12:37 am

1 stop8h 12m

$299

Flights are sorted by cheapest round-trip flights first.

Deals found on 6/10

Showing 1-10 of 60 results
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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 $276). Flying from Region of Ontario to San Francisco in June is currently the most expensive (average of $364). 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 junio 12, 2025.

Regardless of the time of day you decide to fly, the ticket price will remain around the same. Book flights from Region of Ontario to San Francisco as you normally would.

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 junio 12, 2025.

The most flights from CAON to SFO are scheduled on a Wednesday (25 on average). You will have fewer flight options on Saturday, which is when the least amount of flights are scheduled (20 on average).

Rainfall in San Francisco by month

Plan your trip to San Francisco by taking into account the average rainfall totals by month.

In terms of precipitation, rainfall in San Francisco ranges from 0.0 - 4.4 inches per month. January is typically the wettest month, when rainfall can reach 4.4 in. July is typically the driest time to visit San Francisco when rainfall is around 0.0 in.

Temperature in San Francisco by month

Plan your trip to San Francisco by taking into account the average temperature totals by month.

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 62.6 F. Travelers looking to avoid the cold should look outside of January, when temperatures are typically at their lowest (around 51.8 F).

Reviews of airlines servicing San Francisco

Get insights into the airlines that provide service to San Francisco. 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. Reviews last updated junio 12, 2025.
See what other customers who have flown with Delta, Alaska Airlines and Porter Airlines from Ontario to San Francisco have to say. You can also see how each airline compares in terms of entertainment options, comfort, food, crew/service, and boarding process.
Delta
8.0
Very good
7,950 reviews

Entertainment

7.9

Crew

8.5

Overall

8.0

Comfort

7.9

Boarding

8.2

Food

7.3

Reviews

1 / 20
10.0
Excellent

Aaron,Oct 2024

TUS - LAX

Delta has consistently been the best U.S. airline for my travels and this flight was no exception
Delta
8.0
Very good
7,950 reviews
Delta
8.0
Very good
7,950 reviews

Entertainment

7.9

Crew

8.5

Overall

8.0

Comfort

7.9

Boarding

8.2

Food

7.3

Reviews

1 / 20
10.0
Excellent

Aaron,Oct 2024

TUS - LAX

Delta has consistently been the best U.S. airline for my travels and this flight was no exception
Alaska Airlines
8.0
Very good
10,000 reviews
Delta
8.0
Very good
7,950 reviews

Entertainment

7.9

Crew

8.5

Overall

8.0

Comfort

7.9

Boarding

8.2

Food

7.3

Reviews

1 / 20
10.0
Excellent

Aaron,Oct 2024

TUS - LAX

Delta has consistently been the best U.S. airline for my travels and this flight was no exception
Porter Airlines
8.0
Very good
288 reviews
Delta
8.0
Very good
7,950 reviews

Entertainment

7.9

Crew

8.5

Overall

8.0

Comfort

7.9

Boarding

8.2

Food

7.3

Reviews

1 / 20
10.0
Excellent

Aaron,Oct 2024

TUS - LAX

Delta has consistently been the best U.S. airline for my travels and this flight was no exception
Air Transat
7.8
Good
396 reviews
Delta
8.0
Very good
7,950 reviews

Entertainment

7.9

Crew

8.5

Overall

8.0

Comfort

7.9

Boarding

8.2

Food

7.3

Reviews

1 / 20
10.0
Excellent

Aaron,Oct 2024

TUS - LAX

Delta has consistently been the best U.S. airline for my travels and this flight was no exception
SWISS
7.5
Good
1,623 reviews
Delta
8.0
Very good
7,950 reviews

Entertainment

7.9

Crew

8.5

Overall

8.0

Comfort

7.9

Boarding

8.2

Food

7.3

Reviews

1 / 20
10.0
Excellent

Aaron,Oct 2024

TUS - LAX

Delta has consistently been the best U.S. airline for my travels and this flight was no exception

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 11.8 mi from the center of San Francisco.

  • 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 WestJet, which is currently one of the cheapest options available, starting at $141. Porter Airlines flights start at $148 while deals on Air Canada start at $153 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 Toronto Region of Waterloo Intl - 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: Porter Airlines (90%), Air Transat (90%), United Airlines (79%).

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

    Looking at all options, your cheapest flight can be booked for $159. While the most popular route (Toronto Pearson Intl - San Francisco) can be booked for $259 on average our data indicates $1,962 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 $276). Flying from Region of Ontario to San Francisco in June is currently the most expensive (average of $364). 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 Ontario?

Book flights to Ontario if you plan to visit one of these locations
Roseville
Mountain View
South San Francisco
Livermore
Turlock
Santa Cruz
Manteca
Fairfield
Watsonville
Antioch
Hollister
Milpitas
Newark
Hayward
Alameda
Sunnyvale
Daly City
Union City
Campbell
Capitola

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Alternative routes for Ontario to San Francisco

See prices for flight routes from nearby airports that may be better suited for you.
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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 junio 12, 2025.
AirlineCheapestAverageFlexibilityOn-time
WestJetCheapest$174Average$326FlexibilityNo cancel feeOn-time60%
United AirlinesCheapest$241Average$530FlexibilityNo cancel feeOn-time69%
Porter AirlinesCheapest$250Average$413FlexibilityNo cancel feeOn-time52%
Air TransatCheapest$265Average$374FlexibilityNo cancel feeOn-time50%
Air CanadaCheapest$267Average$463FlexibilityNo cancel feeOn-time67%
DeltaCheapest$308Average$466FlexibilityNo cancel feeOn-timeN/A
American AirlinesCheapest$319Average$496FlexibilityNo cancel feeOn-time71%

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