ONT - SFO

C$ 79 Find Cheap Flights from Ontario to San Francisco

This is the cheapest round-trip flight price found by a KAYAK user in the last 72 hours by searching for a flight from Ontario to San Francisco departing on 24/5. Fares are subject to change and may not be available on all flights or dates of travel. Click the price to replicate the search for this deal.
1 adult

KAYAK searches hundreds of travel sites at once for deals on flights to San Francisco

 
These are the airlines KAYAK users have selected most often from within our search results in flight searches from Ontario to San Francisco, as well as popular online travel agencies
These are the airlines KAYAK users have selected most often from within our search results in flight searches from Ontario to San Francisco, as well as popular online travel agencies
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Cheap Flight Deals from Ontario to San Francisco (ONT-SFO)

 
Here are some of the best deals found on KAYAK recently from the most popular airlines for round-trip flights from Ontario to San Francisco that are departing in the next months. While these flights were available on KAYAK in the last 72 hours, prices and availability are subject to change and deals may expire.

Recent round-trip flight deals from Ontario to San Francisco

KAYAK's recommended round-trip deals from the most popular airlines that fly from Ontario to San Francisco.
Discover the best prices for you by selecting your travel dates on KAYAK.
Choose your dates
United Airlines Logo
1:36 p.m. - 3:03 p.m.ONT-SFO
1h 27mdirect
United Airlines Logo
9:18 p.m. - 10:45 p.m.SFO-ONT
1h 27mdirect
C$ 79United Airlines
Find Deal
sam., 24 mai - mer., 28 mai
United Airlines Logo
6:00 a.m. - 7:27 a.m.ONT-SFO
1h 27mdirect
United Airlines Logo
10:45 a.m. - 12:14 p.m.SFO-ONT
1h 29mdirect
C$ 93United Airlines
Find Deal
lun., 5 mai - jeu., 5 juin
United Airlines Logo
6:00 a.m. - 7:27 a.m.ONT-SFO
1h 27mdirect
United Airlines Logo
9:18 p.m. - 10:45 p.m.SFO-ONT
1h 27mdirect
C$ 119United Airlines
Find Deal
jeu., 12 juin - jeu., 19 juin
United Airlines Logo
6:34 p.m. - 8:01 p.m.ONT-SFO
1h 27mdirect
United Airlines Logo
9:18 p.m. - 10:45 p.m.SFO-ONT
1h 27mdirect
C$ 128United Airlines
Find Deal
ven., 20 juin - dim., 22 juin
United Airlines Logo
3:10 p.m. - 4:53 p.m.ONT-SFO
1h 43mdirect
United Airlines Logo
7:05 p.m. - 8:34 p.m.SFO-ONT
1h 29mdirect
C$ 155United Airlines
Find Deal
sam., 10 mai - sam., 10 mai
Southwest Logo
3:40 p.m. - 10:30 p.m.ONT-SFO
6h 50m1 stop
Southwest Logo
5:15 a.m. - 12:20 p.m.SFO-ONT
7h 05m1 stop
C$ 209Southwest
Find Deal
sam., 10 mai - mar., 13 mai
Southwest Logo
7:35 p.m. - 11:25 p.m.ONT-SFO
3h 50m1 stop
Southwest Logo
5:40 a.m. - 11:00 a.m.SFO-ONT
5h 20m1 stop
C$ 238Southwest
Find Deal
jeu., 22 mai - mer., 28 mai
Alaska Airlines Logo
6:00 a.m. - 5:11 p.m.ONT-SFO
11h 11m2 stops
Alaska Airlines Logo
8:49 p.m. - 3:50 p.m.SFO-ONT
19h 01m1 stop
C$ 399Alaska Airlines
Find Deal
mar., 10 juin - mar., 10 juin
Alaska Airlines Logo
11:51 a.m. - 11:53 p.m.ONT-SFO
12h 02m2 stops
Alaska Airlines Logo
1:55 p.m. - 10:46 p.m.SFO-ONT
8h 51m2 stops
C$ 406Alaska Airlines
Find Deal
mer., 28 mai - mar., 3 juin
American Airlines Logo
10:00 a.m. - 4:03 p.m.ONT-SFO
6h 03m1 stop
American Airlines Logo
3:50 p.m. - 9:57 p.m.SFO-ONT
6h 07m1 stop
C$ 488American Airlines
Find Deal
lun., 2 juin - mer., 4 juin

Expert advice for your flight from Ontario to San Francisco

 
Snippets provided in this section are AI-generated based on a summarization of KAYAK-commissioned articles. The articles are presented as-is, for general informational purposes only, and may not be up-to-date. The opinions contained in the articles are specific to the author and reflect their authentic experience, which may vary significantly from the experience of others.
KAYAK teamed up with top travel experts to share the best tips for your journey.
Airlines
Air Canada

Air Canada's Wi-Fi is available on some flights; check availability five days before departure.


Air Canada offers priority check-in for higher fare classes and elite status passengers.

Read more about Air Canadaby Stefanie Waldek
United Airlines

United's Priority Boarding puts you in Zone 2, avoiding carry-on gate-checking.


United offers free messaging on most flights; T-Mobile customers get free streaming Wi-Fi.

Our travel experts
Stefanie Waldek

Stefanie Waldek

Expert on Air Canada and United Airlines

Stefanie Waldek

Stefanie Waldek

Stefanie Waldek is a freelance space, travel, and design writer based in Saratoga Springs, NY. Her words have appeared in Space.com, Travel + Leisure, Condé Nast Traveler, Architectural Digest, and House Beautiful, among other publications. An expert in aviation and expedition cruising, Stefanie is frequently up in the air or on the sea, likely en route to Antarctica or the Arctic.

Read more

KAYAK's insights & trends for Ontario to San Francisco flights

Get data-powered insights and trends into flights from Ontario to San Francisco to help you find the cheapest flights, the best time to fly and much more.

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

To calculate monthly average prices, KAYAK takes all prices for each month over the last year for round-trip flights from Ontario to San Francisco, removes the top 0.1% to account for outliers, and then takes the median of all values for each month.
The cheapest month for flights from Ontario to San Francisco is July, where tickets cost C$ 118 (return) on average. On the other hand, the most expensive months are November and December, where the average cost of round-trip tickets is C$ 208 and C$ 189 respectively.

Can I save money by flying with a layover from Ontario to San Francisco?

The average round-trip price for all non-stop flights, flights with one layover, and flights with two layovers for the route found by users searching on KAYAK in the last 2 weeks.
No, with an average price for the route of C$ 175, prices are generally cheapest when you fly direct.

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

To calculate weekly average prices, KAYAK takes all prices for each week before departure over the last year for round-trip flights from Ontario to San Francisco, removes the top 0.1% to account for outliers, and then takes the average of all the values for each week.
To get a below average price on the flight from Ontario to San Francisco, you should book around 2 weeks before departure. For the absolute cheapest price, our data suggests you should book 5 weeks before departure.

Good to know

Low season

December

High season

May

Cheapest flight

C$ 79
Best time to beat the crowds but there is an average 25% increase in price.
Most popular time to fly and prices are also 19% lower on average.
Flight from Ontario to San Francisco

When to book flights from Ontario to San Francisco

Are your dates flexible? Find out the best times to travel from Ontario to San Francisco based on our flight data from the last year. Discover the cheapest month and even day to fly.
Estimated round-trip price
KAYAK looks at all historical flight data for each date to provide a predicted price for one-way trips or round-trips with a duration up to 40 days. While we try to provide actual minimum prices for each date, some prices are predictions and actual prices may differ.

FAQs for booking flights from Ontario to San Francisco

  • What is the cheapest flight from Ontario to San Francisco?

    In the last 3 days, the lowest price for a flight from Ontario to San Francisco was C$ 58 for a one-way ticket and C$ 57 for a round-trip.

  • Which airlines offer Wi-Fi service onboard planes from Ontario to San Francisco?

    Alaska Airlines, Delta, Japan Airlines, and American Airlines offer inflight Wi-Fi service on the Ontario to San Francisco flight route.

  • Which aircraft models fly most regularly from Ontario to San Francisco?

    The Airbus A320neo is the aircraft model that flies most regularly on the Ontario to San Francisco flight route.

  • Which airline alliances offer flights from Ontario to San Francisco?

    Star Alliance is the only airline alliance operating flights between Ontario and San Francisco.

  • On which days can I fly direct from Ontario to San Francisco?

    There are direct flights from Ontario to San Francisco on a daily basis.

  • How does KAYAK find such low prices on flights from Ontario to San Francisco?

    KAYAK is a travel search engine. That means we look across the web to find the best prices we can find for our users. With over 2 billion flight queries processed yearly, we are able to display a variety of prices and options on flights from Ontario to San Francisco.

  • How does KAYAK's flight Price Forecast tool help me choose the right time to buy my flight ticket from Ontario to San Francisco?

    KAYAK’s flight Price Forecast tool uses historical data to determine whether the price for a flight to San Francisco from Ontario is likely to change within 7 days, so travelers know whether to wait or book now.

  • What is the Hacker Fare option on flights from Ontario to San Francisco?

    Hacker Fares allow you to combine one-way tickets in order to save you money over a traditional round-trip ticket. You could then fly to San Francisco with an airline and back to Ontario with another airline.

  • What is KAYAK's "flexible dates" feature and why should I care when looking for a flight from Ontario to San Francisco?

    Sometimes travel dates aren't set in stone. If your preferred travel dates have some wiggle room, flexible dates will show you all the options when flying to San Francisco from Ontario up to 3 days before/after your preferred dates. You can then pick the flights that suit you best.

See more FAQs

KAYAK’s top tips for finding a cheap flight from Ontario to San Francisco

  • Looking for a cheap flight? 25% of our users found flights on this route for C$ 67 or less one-way and C$ 542 or less round-trip.

Prefer to fly direct from Ontario to San Francisco?

Find which airlines fly direct from Ontario Airport to San Francisco Airport, which days they fly and book direct flights.

Direct departures

Ontario to San Francisco

Monday

Air Canada,Copa Airlines,Emirates, +2 more

Air Canada,Copa Airlines, +3 more

Tuesday

Air Canada,Copa Airlines,Emirates, +1 more

Air Canada,Copa Airlines, +2 more

Wednesday

Air Canada,Copa Airlines,Emirates, +1 more

Air Canada,Copa Airlines, +2 more

Thursday

Air Canada,Copa Airlines,Emirates, +2 more

Air Canada,Copa Airlines, +3 more

Friday

Air Canada,Copa Airlines,Emirates, +2 more

Air Canada,Copa Airlines, +3 more

Saturday

Air Canada,Copa Airlines,Emirates, +2 more

Air Canada,Copa Airlines, +3 more

Sunday

Air Canada,Copa Airlines,Emirates, +2 more

Air Canada,Copa Airlines, +3 more

See more nonstop flights

Direct returns

San Francisco to Ontario

Monday

Air Canada,Emirates,Frontier, +1 more

Air Canada,Emirates, +2 more

Tuesday

Air Canada,Emirates,United Airlines

Air Canada,Emirates, +1 more

Wednesday

Air Canada,Emirates,United Airlines

Air Canada,Emirates, +1 more

Thursday

Air Canada,Emirates,Frontier, +1 more

Air Canada,Emirates, +2 more

Friday

Air Canada,Emirates,Frontier, +1 more

Air Canada,Emirates, +2 more

Saturday

Air Canada,Emirates,Frontier, +1 more

Air Canada,Emirates, +2 more

Sunday

Air Canada,Emirates,Frontier, +1 more

Air Canada,Emirates, +2 more

See more nonstop flights
See more nonstop flights

Top airline flying from Ontario to San Francisco

 
See real verified KAYAK customer reviews for airlines flying from Ontario to San Francisco. Airline scores are aggregated from all reviews left by passengers on KAYAK after flying with an airline. KAYAK doesn’t show reviews that are older than 5 years. Learn how KAYAK collects reviews.
Need help choosing which airline to fly with from Ontario to San Francisco? KAYAK airline reviews give an overall score for each airline based on loads of factors, including comfort, boarding, in-flight entertainment and more, to make your decision easier. See airline scores according to verified KAYAK customer reviews.
5.9
FrontierOverall score based on 3283 reviews
4.6Entertainment
5.6Comfort
4.8Food
6.8Crew
6.2Boarding
Airline reviews

The seats were hard molded plastic covered in plastic vinyl. And the scam to charge people extra to sit together. Don’t they know we can just ask someone to trade seats. And watching the staff separate young children from parents… super classy. We had to guilt them into offering up our seats. This companies policies suck. Don’t give them your money.

2.0 MediocreAnonymous, Apr 2025PDX - LAX
Read more Frontier reviews

The seats were hard molded plastic covered in plastic vinyl. And the scam to charge people extra to sit together. Don’t they know we can just ask someone to trade seats. And watching the staff separate young children from parents… super classy. We had to guilt them into offering up our seats. This companies policies suck. Don’t give them your money.

The seats were awful, hard plastic covered in sheet vinyl. The airline tries to scam you into paying extra to get seat together when the flight wasn’t full. They were going to separate a family with young children but my wife who had a row to herself gave up her seat so the young mom could be with her young boys. I’m never giving this airline my money again.

It was a short flight so no food or entertainment….

Frontier had yet another flight cancellation. Have never made a complete round trip with this airline without at least one leg getting cancelled. Miserable flights - dirty, uncomfortable planes that apparently always have issues since I've had multiple delays and cancellations with them.

Flight was delayed 3 times, would have been nice to have received text message instead of email notifications. Frontier app wasn’t even updated accordingly, no gate number disclosed. No agent at front desk of gate to inform of delay. Very confused and left if the dark

Everything went as planned. Crew was great. Seats were still not that comfortable.

They changed the timing , first delayed by 4 hours then went back to 40 mins late, we had to run back to airport to not miss our flight. This is ridiculous

No frills for sure. No gate announcements about flight delay, not even water to drink on the flight.

I loked walking out on the tarmac to board and no first class. I didn't like that they have no snacks or onboard wifi to bide your time.

The plane was clean, the crew was friendly and helpful. It’s a low cost airline so there was no food, drinks or in flight entertainment but we didn’t expect any of these things. In the room for improvement department, they should install USB ports in seats to charge mobile devices.

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

Information on your arrival and departure airports

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