What is the cheapest airline that flies from Ontario to San Francisco?

Frontier, United Airlines, and Southwest are the most popular carriers operating from Ontario to San Francisco

What airlines fly to San Francisco?

Frontier, United Airlines and Alaska Airlines are the top three most popular airlines that fly to San Francisco from Ontario according to our data. Frontier is the first choice among our users, with 37% of people opting to fly with this airline when traveling to San Francisco. Keep in mind that there are 11 different airlines that fly to San Francisco on a routine basis, so you have a few additional options to choose from.

How many flights depart from Ontario to San Francisco on average per week?

As of August 2025, there are 41 flights per week flying from Ontario to San Francisco. The most common day of the week flights depart is Wed, with 20% of flights taking off on this day.

How many flights depart from Ontario to San Francisco on average per day?

The number of flights available between Ontario and San Francisco is 5 per day as of August 2025. The most frequent departure time is 1:00PM, with 44% of daily flights leaving in the evening.

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?

There are 6 operators available for flights from Ontario Airport to San Francisco Airport as of August 2025.

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.

$37 Cheap Flights from Ontario to San Francisco in 2025

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Find the cheapest flights from Ontario to San Francisco

Round-trip

One-way

Last minute

Direct

Cheap round-trip flights

9:46 pm - 11:15 pmONT-SFO

1h 29mnonstop

10:11 pm - 11:38 pmSFO-ONT

1h 27mnonstop

$79Frontier

Find Deal

Mon, Sep 15 - Fri, Sep 19

9:46 pm - 11:15 pmONT-SFO

1h 29mnonstop

10:11 pm - 11:38 pmSFO-ONT

1h 27mnonstop

$80Frontier

Find Deal

Thu, Sep 11 - Mon, Sep 15

9:46 pm - 11:15 pmONT-SFO

1h 29mnonstop

10:11 pm - 11:38 pmSFO-ONT

1h 27mnonstop

$81Frontier

Find Deal

Thu, Sep 11 - Mon, Sep 15

9:46 pm - 11:15 pmONT-SFO

1h 29mnonstop

10:11 pm - 11:38 pmSFO-ONT

1h 27mnonstop

$82Frontier

Find Deal

Thu, Sep 11 - Mon, Sep 15

10:50 pm - 12:19 amONT-SFO

1h 29mnonstop

10:38 pm - 12:07 amSFO-ONT

1h 29mnonstop

$83Frontier

Find Deal

Fri, Oct 17 - Mon, Oct 20

10:50 pm - 12:19 amONT-SFO

1h 29mnonstop

10:38 pm - 12:07 amSFO-ONT

1h 29mnonstop

$84Frontier

Find Deal

Fri, Oct 24 - Sun, Oct 26

9:46 pm - 11:15 pmONT-SFO

1h 29mnonstop

10:11 pm - 11:38 pmSFO-ONT

1h 27mnonstop

$85Frontier

Find Deal

Thu, Sep 4 - Fri, Sep 5

10:40 pm - 12:15 amONT-SFO

1h 35mnonstop

10:11 pm - 11:38 pmSFO-ONT

1h 27mnonstop

$86Frontier

Find Deal

Fri, Sep 12 - Sun, Sep 14

10:40 pm - 12:15 amONT-SFO

1h 35mnonstop

10:11 pm - 11:38 pmSFO-ONT

1h 27mnonstop

$87Frontier

Find Deal

Fri, Sep 12 - Mon, Sep 15

6:00 am - 7:19 amONT-SFO

1h 19mnonstop

4:17 pm - 5:37 pmSFO-ONT

1h 20mnonstop

$123United Airlines

Find Deal

Thu, Sep 4 - Sun, Sep 7

Frontier flights from Ontario to San Francisco

Our best Frontier deals on Ontario to San Francisco flight tickets

Frontier

Sep 15

ONT9:46 pmOntario

1h 29m

SFO11:15 pmSan Francisco

Sep 19

SFO10:11 pmSan Francisco

1h 27m

ONT11:38 pmOntario

$79

Find similar

Frontier

Sep 11

ONT9:46 pmOntario

1h 29m

SFO11:15 pmSan Francisco

Sep 15

SFO10:11 pmSan Francisco

1h 27m

ONT11:38 pmOntario

$80

Find similar

Frontier

Sep 11

ONT9:46 pmOntario

1h 29m

SFO11:15 pmSan Francisco

Sep 15

SFO10:11 pmSan Francisco

1h 27m

ONT11:38 pmOntario

$81

Find similar

United Airlines flights from Ontario to San Francisco

Our best United Airlines deals on Ontario to San Francisco flight tickets

United Airlines

Sep 3

ONT1:42 pmOntario

1h 19m

SFO3:01 pmSan Francisco

Sep 5

SFO10:45 amSan Francisco

1h 28m

ONT12:13 pmOntario

$117

Find similar

United Airlines

Sep 4

ONT6:00 amOntario

1h 19m

SFO7:19 amSan Francisco

Sep 7

SFO4:17 pmSan Francisco

1h 20m

ONT5:37 pmOntario

$123

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Fly from

Fly to

Route

Depart

Return

Price

OntarioSan Francisco

ONT - SFO

ONTSFO

Ontario

Mon 9/15

9:46 pm-11:15 pm

Nonstop1h 29m

San Francisco

Fri 9/19

10:11 pm-11:38 pm

Nonstop1h 27m

$79

OntarioSan Francisco

ONT - SFO

ONTSFO

Ontario

Thu 9/11

9:46 pm-11:15 pm

Nonstop1h 29m

San Francisco

Mon 9/15

10:11 pm-11:38 pm

Nonstop1h 27m

$80

OntarioSan Francisco

ONT - SFO

ONTSFO

Ontario

Thu 9/11

9:46 pm-11:15 pm

Nonstop1h 29m

San Francisco

Mon 9/15

10:11 pm-11:38 pm

Nonstop1h 27m

$81

OntarioSan Francisco

ONT - SFO

ONTSFO

Ontario

Thu 9/11

9:46 pm-11:15 pm

Nonstop1h 29m

San Francisco

Mon 9/15

10:11 pm-11:38 pm

Nonstop1h 27m

$82

OntarioSan Francisco

ONT - SFO

ONTSFO

Ontario

Fri 10/17

10:50 pm-12:19 am

Nonstop1h 29m

San Francisco

Mon 10/20

10:38 pm-12:07 am

Nonstop1h 29m

$83

OntarioSan Francisco

ONT - SFO

ONTSFO

Ontario

Fri 10/24

10:50 pm-12:19 am

Nonstop1h 29m

San Francisco

Sun 10/26

10:38 pm-12:07 am

Nonstop1h 29m

$84

OntarioSan Francisco

ONT - SFO

ONTSFO

Ontario

Thu 9/4

9:46 pm-11:15 pm

Nonstop1h 29m

San Francisco

Fri 9/5

10:11 pm-11:38 pm

Nonstop1h 27m

$85

OntarioSan Francisco

ONT - SFO

ONTSFO

Ontario

Fri 9/12

10:40 pm-12:15 am

Nonstop1h 35m

San Francisco

Sun 9/14

10:11 pm-11:38 pm

Nonstop1h 27m

$86

OntarioSan Francisco

ONT - SFO

ONTSFO

Ontario

Fri 9/12

10:40 pm-12:15 am

Nonstop1h 35m

San Francisco

Mon 9/15

10:11 pm-11:38 pm

Nonstop1h 27m

$87

OntarioSan Francisco

ONT - SFO

ONTSFO

Ontario

Thu 9/4

6:00 am-7:19 am

Nonstop1h 19m

San Francisco

Sun 9/7

4:17 pm-5:37 pm

Nonstop1h 20m

$123

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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

Prices

Airlines

Other information

What is the cheapest month to fly to San Francisco?

If you aren’t able to travel to San Francisco during the month of May, then flying in February is also cheap. Prices for this month can be found on momondo for an average of $99.

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 Friday when prices can be found for as low as $179. The most expensive day to fly to San Francisco is Sunday, with ticket prices averaging around $295.

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 afternoon. Our users have found flights to San Francisco in the afternoon for as low as $156. Flights in the evening are often more expensive with an average ticket price of $595.

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?

You are more likely to see cheaper flights to San Francisco from Ontario when booking weeks ahead of your departure date. In general, you can expect to find flights to San Francisco for around $121 when searching weeks out. However, flight prices might be lower outside of this timeframe. For example, people recently found flights to San Francisco from Ontario for as low as $98 on momondo.

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 August 2025, prices for Ontario to San Francisco flights are approximately 5% 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	$85
Fastest flight time	1h 18m
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 $85. The best round-trip flight deal from Ontario to San Francisco found on momondo in the last 72 hours is $124.

The fastest flight from Ontario to San Francisco takes 1h 18m

Direct flights go from Ontario to San Francisco every day.

There is 1 airport near San Francisco: San Francisco (SFO)

Search flight deals

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 19m.
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?
There are 6 operators available for flights from Ontario Airport to San Francisco Airport as of August 2025.
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?
Based on momondo bookings for this flight route, the most popular plane model on flight routes from Ontario to San Francisco is Boeing 737-800 (17.59% of total bookings). The next most popular plane models are Airbus A320-100/200 (15.41%), Airbus A320neo (13.28%), and Airbus A321neo (8.77%).
What is the most popular airline from Ontario to San Francisco?
momondo data reveals that the most frequently booked airline on the route from Ontario to San Francisco is Frontier, representing 55% of all bookings. The subsequent popular airlines are United Airlines at 43%, Alaska Airlines at 1%, and Southwest at 0%.

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
Frontier	PriceFrom $35	Free Cancellation	Rating 5.8 3,207 reviews	Search Frontier flights
Spirit Airlines	PriceFrom $37	Free Cancellation	Rating 6.3 8,039 reviews	Search Spirit Airlines flights
United Airlines	PriceFrom $58	Free Cancellation	Rating 7.4 8,928 reviews	Search United Airlines flights
Alaska Airlines	PriceFrom $67	Free Cancellation	Rating 8.0 10,000 reviews	Search Alaska Airlines flights
Delta	PriceFrom $85	Free Cancellation	Rating 7.9 7,982 reviews	Search Delta flights
Southwest	PriceFrom $116	Free Cancellation	Rating 8.0 4,246 reviews	Search Southwest flights

United Airlines Flights From Ontario to San Francisco
United Airlines flight deals from Ontario to San Francisco start from $58 round-trip. Over the 14 United Airlines flights for this route in a normal week, average airfare is usually $200 round-trip - but some users have found much cheaper deals with momondo.
Frontier Flights From Ontario to San Francisco
Across 3,207 Frontier reviews on momondo, the average score is 5.8/10. Frontier flies from Ontario to San Francisco about 4 times each week, with ticket deals ranging from $35 to $94. Price data is based on momondo searches in the last 72 hours.

Santa Cruz

Carmel-by-the-Sea

Modesto

Calistoga

Sonoma

Hayward

Bodega Bay

Roseville

Santa Clara

Big Sur

Daly City

Fremont

Berkeley

Walnut Creek

Half Moon Bay

Vallejo

South San Francisco

Redwood City

Pacific Grove

Sunnyvale

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.

An easier way to manage your San Francisco trip

We make it super easy to schedule, organize and travel with friends or family. Trips is free — and available to use no matter where you book.

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Cheap flights from Ontario to San Francisco from $53

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 8/31. 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

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Cheap last minute flights

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Frontier flights from Ontario to San Francisco

Our best Frontier deals on Ontario to San Francisco flight tickets

United Airlines flights from Ontario to San Francisco

Our best United Airlines deals on Ontario to San Francisco flight tickets

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

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 May, then flying in February is also cheap. Prices for this month can be found on momondo for an average of $99.

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 Friday when prices can be found for as low as $179. The most expensive day to fly to San Francisco is Sunday, with ticket prices averaging around $295.

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 afternoon. Our users have found flights to San Francisco in the afternoon for as low as $156. Flights in the evening are often more expensive with an average ticket price of $595.

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?

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 August 2025, prices for Ontario to San Francisco flights are approximately 5% cheaper when compared to flights at the same time last year.

What is the cheapest airline that flies from Ontario to San Francisco?

Frontier, United Airlines, and Southwest are the most popular carriers operating from Ontario to San Francisco

What airlines fly to San Francisco?

How many flights depart from Ontario to San Francisco on average per day?

The number of flights available between Ontario and San Francisco is 5 per day as of August 2025. The most frequent departure time is 1:00PM, with 44% of daily flights leaving in the evening.

How many flights depart from Ontario to San Francisco on average per week?

As of August 2025, there are 41 flights per week flying from Ontario to San Francisco. The most common day of the week flights depart is Wed, with 20% of flights taking off on this day.

When to book flights from Ontario to San Francisco

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

Fastest flight time

Direct flights

Airports in San Francisco

How far is Ontario to San Francisco by plane?

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

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?

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

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

United Airlines Flights From Ontario to San Francisco

Frontier Flights From Ontario to San Francisco

Traveling to a place near San Francisco?

Why use momondo?

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

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

How can momondo help me find flights 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?

An easier way to manage your San Francisco trip

We make it super easy to schedule, organize and travel with friends or family. Trips is free — and available to use no matter where you book.

Get notified when prices go down

Daily price changes in your inbox - only with Price Alerts.

Find better results for your trip to the United States

Airports servicing California