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Cheap flights from Ontario to San Francisco from $21

This is the cheapest one-way flight price found by a momondo user in the last 72 hours by searching for a flight from Ontario to San Francisco departing on 3/2. Fares may change, and may not be available for all flights or travel dates. Click the price to refresh the search for this deal.
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Find the cheapest flights from Ontario to San Francisco

Cheap round-trip flights

These are some of the best round-trip flight deals from Ontario to San Francisco that have been recently found on momondo from popular airlines, departing in the coming months.

Cheap one-way flights

Flying one-way? These are some of the best deals recently discovered on momondo for flights from Ontario to San Francisco.

Cheap last minute flights

Planning a quick getaway from Ontario to San Francisco? These are the last-minute flight deals available now.

Cheap direct flights

If you prefer a non-stop journey, check out our latest direct flight deals to San Francisco, so you can enjoy a seamless trip without layovers.

Cheap bus & train deals from Ontario to San Francisco

Find recent round-trip train or bus tickets from Ontario to San Francisco.

All round-trip flight deals to San Francisco

The cheapest plane tickets to San Francisco found on KAYAK recently.
6:00 am - 7:35 amONT-SFO
1h 35mnonstop
8:06 am - 9:34 amSFO-ONT
1h 28mnonstop
$38Frontier
Find Deal
Fri, Feb 7 - Thu, Feb 13
6:00 am - 7:35 amONT-SFO
1h 35mnonstop
9:59 pm - 11:24 pmSFO-ONT
1h 25mnonstop
$39Frontier
Find Deal
Fri, Feb 7 - Sun, Feb 9
3:30 pm - 5:14 pmONT-SFO
1h 44mnonstop
7:10 pm - 8:40 pmSFO-ONT
1h 30mnonstop
$52United Airlines
Find Deal
Sat, Feb 15 - Sat, Feb 15
10:47 am - 12:20 pmONT-SFO
1h 33mnonstop
8:25 am - 9:51 amSFO-ONT
1h 26mnonstop
$117United Airlines
Find Deal
Sat, Feb 8 - Mon, Feb 10
5:40 am - 10:35 amONT-SFO
4h 55m1 stop
5:55 am - 10:55 amSFO-ONT
5h 00m1 stop
$136Southwest
Find Deal
Sat, Feb 1 - Fri, Feb 7
6:00 am - 1:38 pmONT-SFO
7h 38m2 stops
8:16 am - 9:44 amSFO-ONT
1h 28mnonstop
Tue, Mar 4 - Fri, Mar 7
6:00 am - 1:47 pmONT-SFO
7h 47m1 stop
8:16 am - 9:44 amSFO-ONT
1h 28mnonstop
Tue, Mar 4 - Fri, Mar 7
5:40 am - 8:15 pmONT-SFO
14h 35m2 stops
5:30 am - 10:00 amSFO-ONT
4h 30m1 stop
$161Southwest
Find Deal
Sat, Feb 1 - Fri, Feb 7
7:00 am - 4:31 pmONT-SFO
9h 31m1 stop
8:10 am - 6:13 pmSFO-ONT
10h 03m2 stops
$188Alaska Airlines
Find Deal
Fri, Jan 31 - Fri, Feb 7
11:14 am - 7:16 pmONT-SFO
8h 02m1 stop
7:55 pm - 10:34 amSFO-ONT
14h 39m1 stop
$192Alaska Airlines
Find Deal
Tue, Feb 4 - Tue, Feb 11
8:26 am - 10:02 amONT-SFO
1h 36mnonstop
$21Frontier
Find Deal
Sun, Mar 2
3:55 pm - 5:38 pmONT-SFO
1h 43mnonstop
$29United Airlines
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Thu, Apr 17
8:26 am - 10:02 amONT-SFO
1h 36mnonstop
$30Frontier
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Thu, Mar 27
10:47 am - 12:20 pmONT-SFO
1h 33mnonstop
$59United Airlines
Find Deal
Sat, Feb 8
3:00 pm - 10:50 pmONT-SFO
7h 50m1 stop
$64Southwest
Find Deal
Sat, Feb 15
6:00 am - 4:07 pmONT-SFO
10h 07m2 stops
$97Alaska Airlines
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Tue, Feb 4
6:10 am - 12:30 pmONT-SFO
6h 20m1 stop
$100American Airlines
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Sun, Jan 19
6:00 am - 7:16 pmONT-SFO
13h 16m2 stops
$102Alaska Airlines
Find Deal
Mon, Feb 10
5:45 am - 5:35 pmONT-SFO
11h 50m1 stop
$120Southwest
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Sun, Jan 19
9:32 am - 4:04 pmONT-SFO
6h 32m1 stop
$130American Airlines
Find Deal
Sat, Mar 8
6:45 am - 8:20 amONT-SFO
1h 35mnonstop
9:59 pm - 11:24 pmSFO-ONT
1h 25mnonstop
$77Frontier
Find Deal
Sun, Jan 12 - Mon, Jan 20
6:45 am - 8:20 amONT-SFO
1h 35mnonstop
9:59 pm - 11:23 pmSFO-ONT
1h 24mnonstop
$78Frontier
Find Deal
Sun, Jan 12 - Mon, Jan 13
6:15 am - 7:46 amONT-SFO
1h 31mnonstop
4:35 pm - 6:04 pmSFO-ONT
1h 29mnonstop
$127United Airlines
Find Deal
Tue, Jan 14 - Tue, Jan 21
10:47 am - 12:20 pmONT-SFO
1h 33mnonstop
4:35 pm - 6:04 pmSFO-ONT
1h 29mnonstop
$137United Airlines
Find Deal
Tue, Jan 14 - Tue, Jan 14
6:10 am - 12:30 pmONT-SFO
6h 20m1 stop
5:55 am - 11:58 amSFO-ONT
6h 03m1 stop
$199American Airlines
Find Deal
Fri, Jan 10 - Sat, Jan 11
12:48 pm - 6:59 pmONT-SFO
6h 11m1 stop
9:15 am - 3:29 pmSFO-ONT
6h 14m1 stop
$218American Airlines
Find Deal
Mon, Jan 13 - Wed, Jan 15
6:45 am - 11:25 amONT-SFO
4h 40m1 stop
6:05 am - 1:25 pmSFO-ONT
7h 20m2 stops
$252Southwest
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Tue, Jan 14 - Wed, Jan 15
9:20 am - 4:10 pmONT-SFO
6h 50m2 stops
6:05 am - 1:25 pmSFO-ONT
7h 20m2 stops
$257Southwest
Find Deal
Tue, Jan 14 - Wed, Jan 15
5:44 pm - 12:52 pmONT-SFO
19h 08m1 stop
9:15 am - 10:13 pmSFO-ONT
12h 58m1 stop
$517Alaska Airlines
Find Deal
Tue, Jan 14 - Fri, Jan 17
6:00 am - 4:31 pmONT-SFO
10h 31m2 stops
8:00 am - 5:04 pmSFO-ONT
9h 04m1 stop
$528Alaska Airlines
Find Deal
Fri, Jan 10 - Tue, Jan 14
6:00 am - 7:35 amONT-SFO
1h 35mnonstop
9:59 pm - 11:24 pmSFO-ONT
1h 25mnonstop
$38Frontier
Find Deal
Fri, Feb 7 - Mon, Feb 10
6:00 am - 7:35 amONT-SFO
1h 35mnonstop
9:59 pm - 11:24 pmSFO-ONT
1h 25mnonstop
$39Frontier
Find Deal
Fri, Feb 7 - Sun, Feb 9
8:26 am - 10:02 amONT-SFO
1h 36mnonstop
8:06 am - 9:34 amSFO-ONT
1h 28mnonstop
$42Frontier
Find Deal
Thu, Feb 20 - Sun, Feb 23
6:00 am - 7:35 amONT-SFO
1h 35mnonstop
9:59 pm - 11:24 pmSFO-ONT
1h 25mnonstop
$48Frontier
Find Deal
Fri, Jan 24 - Sun, Jan 26
6:00 am - 7:35 amONT-SFO
1h 35mnonstop
8:06 am - 9:34 amSFO-ONT
1h 28mnonstop
$50Frontier
Find Deal
Fri, Feb 7 - Fri, Feb 14
3:30 pm - 5:14 pmONT-SFO
1h 44mnonstop
7:10 pm - 8:40 pmSFO-ONT
1h 30mnonstop
$52United Airlines
Find Deal
Sat, Feb 15 - Sat, Feb 15
8:26 am - 10:02 amONT-SFO
1h 36mnonstop
8:06 am - 9:34 amSFO-ONT
1h 28mnonstop
$53Frontier
Find Deal
Fri, Feb 21 - Mon, Feb 24
6:15 am - 7:46 amONT-SFO
1h 31mnonstop
4:35 pm - 6:04 pmSFO-ONT
1h 29mnonstop
$57United Airlines
Find Deal
Sun, Jan 26 - Wed, Jan 29
6:45 am - 8:20 amONT-SFO
1h 35mnonstop
9:59 pm - 11:24 pmSFO-ONT
1h 25mnonstop
$58Frontier
Find Deal
Sun, Jan 19 - Sun, Jan 19
8:26 am - 10:02 amONT-SFO
1h 36mnonstop
8:06 am - 9:34 amSFO-ONT
1h 28mnonstop
$60Frontier
Find Deal
Thu, Feb 13 - Mon, Feb 17

Frontier flights from Ontario to San Francisco

Our best Frontier deals on Ontario to San Francisco flight tickets
Frontier
Feb 7
ONT6:00 amOntario
1h 35m
SFO7:35 amSan Francisco
Feb 13
SFO8:06 amSan Francisco
1h 28m
ONT9:34 amOntario
Frontier
Feb 7
ONT6:00 amOntario
1h 35m
SFO7:35 amSan Francisco
Feb 9
SFO9:59 pmSan Francisco
1h 25m
ONT11:24 pmOntario
Frontier
Feb 20
ONT8:26 amOntario
1h 36m
SFO10:02 amSan Francisco
Feb 23
SFO8:06 amSan Francisco
1h 28m
ONT9:34 amOntario

Southwest flights from Ontario to San Francisco

Our best Southwest deals on Ontario to San Francisco flight tickets
Southwest
Feb 1
ONT5:40 amOntario
4h 55m
1 stop
SFO10:35 amSan Francisco
Feb 7
SFO5:55 amSan Francisco
5h 00m
1 stop
ONT10:55 amOntario
Southwest
Feb 1
ONT5:40 amOntario
14h 35m
2 stops
SFO8:15 pmSan Francisco
Feb 7
SFO5:30 amSan Francisco
4h 30m
1 stop
ONT10:00 amOntario
Southwest
Feb 1
ONT10:05 amOntario
8h 05m
1 stop
SFO6:10 pmSan Francisco
Feb 3
SFO6:05 amSan Francisco
7h 20m
2 stops
ONT1:25 pmOntario

See travel insights to San Francisco from

How to get the cheapest flight ticket from Ontario to San Francisco

Look no further. We've gone through all the searches for this route on momondo so you have the important information and insights to find the cheapest flight ticket for your trip

What is the cheapest month to fly to San Francisco?

If you aren’t able to travel to San Francisco during the month of July, then flying in April is also cheap. Prices for this month can be found on momondo for an average of $86.

What is the cheapest day to depart on your flight to San Francisco?

The cheapest day to depart from Ontario to San Francisco is on a Wednesday when prices can be found for as low as $118. The most expensive day to fly to San Francisco is Sunday, with ticket prices averaging around $159.

What is the cheapest time of day to depart on your flight to San Francisco?

Our data shows that the cheapest Ontario to San Francisco flights are usually those with departure times in the morning. Our users have found flights to San Francisco in the morning for as low as $127. Flights in the evening are often more expensive with an average ticket price of $162.

What is the cheapest Ontario to San Francisco flight route?

Fly from Ontario to San Francisco for the best Ontario - San Francisco flight prices

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

The ideal time to book your flight to San Francisco is 47 days in advance when prices tend to average $123. In the past 72 hours, momondo users found flights from Ontario to San Francisco for as low as $60.

What cabin class options are available on Ontario to San Francisco flights?

There are 4 cabin classes available to choose from on Ontario to San Francisco flights. Cabin price and availability will vary by airline so perform a search above to find the right deals for you.

How have Ontario to San Francisco flight prices changed over time?

As of January 2025, prices for Ontario to San Francisco flights are approximately 28% cheaper when compared to flights at the same time last year.

When to book flights from Ontario to San Francisco

Are you open to changing your travel dates? Check out the ideal times to fly from Ontario to San Francisco according to our flight data. Find out which month and days have the cheapest flights.
Estimated round-trip price

Cheap Ontario to San Francisco (ONT to SFO) flight deals and tips

Find info about flight duration, direct flights, and airports for your flight from Ontario to San Francisco

Best Price Found

$21

Fastest flight time

1h 29m

Direct flights

Every day

Airports in San Francisco

1 airport
The best one-way flight to San Francisco from Ontario in the past 72 hours is $21. The best round-trip flight deal from Ontario to San Francisco found on momondo in the last 72 hours is $38.
The fastest flight from Ontario to San Francisco takes 1h 29m
Direct flights go from Ontario to San Francisco every day.
There is 1 airport near San Francisco: San Francisco (SFO)

  • How far is Ontario to San Francisco by plane?

    The straight-line distance from Ontario to San Francisco is 370.2 mi. In terms of flight time, this usually takes a little over 1h 29m.

  • When did momondo last update prices for flights from Ontario Airport to San Francisco Airport?

    Prices for flights from Ontario Airport to San Francisco Airport are updated daily.

  • How many operators does momondo search for flights from Ontario Airport to San Francisco Airport?

  • How old do you have to be to fly from Ontario Airport to San Francisco Airport?

    The minimum age a child must be to fly alone is five but airlines that offer an unaccompanied minor (UNMR) service will have their own age restrictions, including rules around flight length, timings, and stopovers. We always recommend checking with the individual airline you are booking with to travel from Ontario Airport to San Francisco Airport.

  • What documentation or ID do you need to fly to San Francisco Airport?

    The necessary travel and health documents for your San Francisco Airport trip may vary depending on your travel plans and individual circumstances. Generally, you should have various documents, such as a national ID card or driver's license and a passport that is valid for six months beyond your scheduled arrival date. We recommend seeking advice from your airline or a trusted third party, such as IATA.

  • What is the most popular plane model from Ontario to San Francisco?

  • What is the most popular airline from Ontario to San Francisco?


Best airlines flying from Ontario to San Francisco

Compare and see reviews for airlines that fly from Ontario to San Francisco with momondo
Airline
Rating
Free Cancellation
Price
Spirit AirlinesPriceFrom $31Free CancellationRating
6.3
8,076 reviews
Search Spirit Airlines flights
FrontierPriceFrom $38Free CancellationRating
6.0
3,428 reviews
Search Frontier flights
Breeze AirwaysPriceFrom $78Free CancellationRating
8.0
141 reviews
Search Breeze Airways flights
DeltaPriceFrom $85Free CancellationRating
8.0
8,501 reviews
Search Delta flights
Alaska AirlinesPriceFrom $108Free CancellationRating
8.0
9,641 reviews
Search Alaska Airlines flights
United AirlinesPriceFrom $124Free CancellationRating
7.4
8,942 reviews
Search United Airlines flights
  • United Airlines Flights From Ontario to San Francisco

    United Airlines flight deals from Ontario to San Francisco start from $124 round-trip. Over the 13 United Airlines flights for this route in a normal week, average airfare is usually $260 round-trip - but some users have found much cheaper deals with momondo.


Why use momondo?

Why should I use momondo to find a flight deal from Ontario to San Francisco?

It is quick and easy to find Ontario to San Francisco flights on momondo. We search and return numerous flight options from various airlines and agents. You can then use our filters to narrow your search until you have found the most convenient flight to San Francisco that suits you.

Can I find flights from Ontario to San Francisco with flexible booking policies on momondo?

Flights from Ontario to San Francisco with flexible booking policies can be found by using the search form above and then selecting our dedicated flexible booking filter, which will highlight only the flights where this policy is applied.

How can momondo help me find flights from Ontario to San Francisco?

momondo offers useful filters to help you find the right flight. Choose specific flight times, airports or even what payment method you prefer. We have numerous options to help you book your ideal flight from Ontario to San Francisco.

I’m not ready to book a flight from Ontario to San Francisco right now. Can momondo alert me if prices change?

Yes momondo offers price alerts on flights to San Francisco from Ontario. After performing a search on this page you should be able to see the price alert set up feature. Simply provide a valid email address and momondo will instantly alert you when prices change.


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