Cheap flights from Ontario to San Francisco (ONT - SFO) from $22

This is the cheapest one-way flight price, found on 9/27. Prices may vary by date and flight preferences.
ONT — SFO
Oct 3 — Oct 101

The best prices from Ontario to San Francisco are usually found in October or March, booked 31 days in advance, depart on a Friday or Thursday and return on a Saturday

How to find the cheapest flight from Ontario (ONT) to San Francisco (SFO)

All the information you need to plan the best ONT to SFO flight in 2023: compare Ontario to San Francisco flight prices with the expected peak season, weather and rainfall in San Francisco.

Popular in

July

Cheapest in

October

Round-trip from

$258

One-way from

$22
High demand for flights, 32% potential price rise
Best time to find cheap flights, 31% potential price drop
From Ontario to San Francisco
One-way flight from Ontario to San Francisco

ONT - SFO

Price

$258 - $436

SFO

Temperature

51.8 - 62.6 °F

SFO

Rainfall

0 - 4.4 inches

What is the cheapest day to fly round-trip from Ontario to San Francisco?

Users have found that flying from Ontario to San Francisco on a Monday typically leans towards higher prices. However, this doesn’t mean you still can’t find a deal. Flexibility with other aspects of your flight can still land a great price for your trip.

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

When searching for a good deal, it’s best to be prepared for potential fluctuations in price. We recommend booking at least 60 days in advance, which can save you up to 62% on flights from Ontario to San Francisco compared to booking the week you need them. Waiting 60 days out may not be for everyone, so we have options available for flights within the next two weeks, with the lowest price starting at $151. For sooner than that we have options available in the next 3 days from $212.

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

January can be a great time to fly to San Francisco from Ontario with a flight ticket averaging about $148. Cheapflights users have found deals in the month of January for as cheap as $88. The most expensive prices can be found in the month of June.

When is the cheapest time to fly from Ontario to San Francisco (ONT - SFO)?

One of the essential ways to save on airfare from Ontario to San Francisco is to remain as flexible as possible. Flights that are in the morning tend to be the most expensive. A flight in the afternoon could potentially save you up to 25% on airfare.

Cheap Frontier flights from Ontario to San Francisco

Take a look at some of the lowest-priced Frontier flights heading from Ontario to San Francisco. Make sure to check back often as deals are often changing.
  • One of the most popular airlines traveling from Ontario to San Francisco is Frontier. Flights from Frontier traveling this route typically cost $228.90 RT. This price is typically 17% cheaper than other airlines that offer Ontario to San Francisco flights. When booking this route, the cheapest RT price found was $94. Ontario Airport is the most common Ontario airport to take off from when flying to San Francisco. San Francisco Airport is the most popular arrival airport in San Francisco. When flying from Ontario to San Francisco, Frontier flights are 4% more popular than any other airline flying that same route.

Cheap United Airlines flights from Ontario to San Francisco

Browse through some of the cheapest United Airlines flights traveling from Ontario to San Francisco. If these deals don't fit your criteria, make sure to check back soon as new deals are always added.
  • If you’re traveling from Ontario to San Francisco, one of the more common airlines traveling that route is United Airlines. Flights from United Airlines traveling this route typically cost $87.92 RT. This price is typically 224% more expensive than other airlines that offer Ontario to San Francisco flights. When booking this route, the cheapest RT price found was $34. The most popular departure airport in Ontario when flying to San Francisco is Ontario Airport. The most popular airport to fly into when visiting San Francisco is San Francisco Airport. When flying from Ontario to San Francisco, United Airlines flights are -18% more popular than any other airline flying that same route.

Cheap Ontario to San Francisco flights in September & October 2023

The best prices found for ONT to SFO flights for September, October
Listed are some of the best fares we've found on flights departing from Ontario to San Francisco in 2023. For more flight deals, be sure to check back very soon.

Ontario to San Francisco 2023 flight deals

Cheap flights to San Francisco from Ontario found for this year
Listed are some of the best fares we've found on flights departing from Ontario to San Francisco in 2023. For more flight deals, be sure to check back very soon.

Non-stop flights to San Francisco from Ontario

Save time with Ontario to San Francisco direct flight deals
For a quicker trip, book one of these direct flights from Ontario to San Francisco. Users can also choose from other Ontario to San Francisco flights by using the search form above.

Ontario to San Francisco flights leaving soon

Late deals on return flights to San Francisco from Ontario, departing today and this week
Book one of these great deals on flights from Ontario to San Francisco. Users should be sure to double check the price, date, and time of their last-minute flight.

One-way flights to San Francisco from Ontario

The cheapest one-way flights from Ontario to San Francisco
Take a look at some of the one-way flights we've detected from Ontario to San Francisco. Users in need of a round-trip flight from Ontario to San Francisco instead should update the search form at the top of page.

Find flights from Ontario to San Francisco within your budget

Use the slider to find flights from Ontario to San Francisco that fit your budget.

Fly from

Any airport

Fly to

Any airport

Budget

$38 - $195

Route

Depart

Return

Price

OntarioSan Francisco

ONT - SFO

ONTSFO

Ontario

Sat 10/28

Nonstop1h 32m

San Francisco

Mon 10/30

Nonstop1h 25m

OntarioSan Francisco

ONT - SFO

ONTSFO

Ontario

Tue 11/7

Nonstop1h 32m

San Francisco

Tue 11/14

Nonstop1h 27m

OntarioSan Francisco

ONT - SFO

ONTSFO

Ontario

Thu 11/30

Nonstop1h 34m

San Francisco

Sat 12/2

Nonstop1h 26m

OntarioSan Francisco

ONT - SFO

ONTSFO

Ontario

Wed 10/25

Nonstop1h 32m

San Francisco

Tue 10/31

Nonstop1h 26m

OntarioSan Francisco

ONT - SFO

ONTSFO

Ontario

Wed 10/18

Nonstop1h 26m

San Francisco

Tue 10/31

Nonstop1h 26m

OntarioSan Francisco

ONT - SFO

ONTSFO

Ontario

Tue 11/7

Nonstop1h 32m

San Francisco

Fri 11/10

Nonstop1h 25m

OntarioSan Francisco

ONT - SFO

ONTSFO

Ontario

Fri 10/27

Nonstop1h 28m

San Francisco

Mon 10/30

Nonstop1h 25m

OntarioSan Francisco

ONT - SFO

ONTSFO

Ontario

Thu 12/7

Nonstop1h 34m

San Francisco

Mon 12/11

Nonstop1h 26m

OntarioSan Francisco

ONT - SFO

ONTSFO

Ontario

Tue 10/24

Nonstop1h 22m

San Francisco

Wed 10/25

Nonstop1h 27m

Flights are sorted by cheapest first

Deals found on 9/27

Reviews of airlines servicing San Francisco

Read reviews from past customers who have flown Frontier, United Airlines and American Airlines from Ontario to San Francisco. You can also see how each airline compares in terms of entertainment options, comfort, food, crew/service, and boarding process.
Alaska Airlines
8.1
Very good
1,394 reviews

Overall

8.1

Entertainment

7.2

Crew

8.6

Food

7.2

Comfort

8.0

Boarding

8.3

Reviews

1 / 10

They lost my luggage on my way to NY and then again on my way to SF, horrible

Alaska Airlines
8.1
Very good
1,394 reviews
Alaska Airlines
8.1
Very good
1,394 reviews

Overall

8.1

Entertainment

7.2

Crew

8.6

Food

7.2

Comfort

8.0

Boarding

8.3

Reviews

1 / 10

They lost my luggage on my way to NY and then again on my way to SF, horrible

Southwest
7.6
Good
1,521 reviews
Alaska Airlines
8.1
Very good
1,394 reviews

Overall

8.1

Entertainment

7.2

Crew

8.6

Food

7.2

Comfort

8.0

Boarding

8.3

Reviews

1 / 10

They lost my luggage on my way to NY and then again on my way to SF, horrible

United Airlines
7.4
Good
1,890 reviews
Alaska Airlines
8.1
Very good
1,394 reviews

Overall

8.1

Entertainment

7.2

Crew

8.6

Food

7.2

Comfort

8.0

Boarding

8.3

Reviews

1 / 10

They lost my luggage on my way to NY and then again on my way to SF, horrible

American Airlines
7.2
Good
2,635 reviews
Alaska Airlines
8.1
Very good
1,394 reviews

Overall

8.1

Entertainment

7.2

Crew

8.6

Food

7.2

Comfort

8.0

Boarding

8.3

Reviews

1 / 10

They lost my luggage on my way to NY and then again on my way to SF, horrible

Avianca
6.9
Okay
960 reviews
Alaska Airlines
8.1
Very good
1,394 reviews

Overall

8.1

Entertainment

7.2

Crew

8.6

Food

7.2

Comfort

8.0

Boarding

8.3

Reviews

1 / 10

They lost my luggage on my way to NY and then again on my way to SF, horrible

Related info for your journey

Useful info, stats and facts about Ontario to San Francisco flights.

What airports do I use to fly from Ontario to San Francisco?

To fly from Ontario to San Francisco, you need to book a flight from Ontario (ONT) to San Francisco (SFO). Nonstop flights to San Francisco from Ontario take 1h 22m on average. When it comes time to book airfare, you have a few options: there are 6 outbound flights from Ontario to San Francisco offered by 8 different airlines.

Can I find flights from Ontario to San Francisco for under $100 on Cheapflights?

Yes, there are multiple flights from Ontario to San Francisco for under $100. The cheapest flight booked recently is on Frontier for just $38, but on average you can expect to pay $55.

Are there nonstop flights from Ontario to San Francisco for under $100 on Cheapflights?

Cheapflights has at least 20 direct flights from Ontario to San Francisco under $100. A good price for a nonstop flight from Ontario to San Francisco is less than $56.

Are there last-minute flights available from Ontario to San Francisco for under $100?

There are currently 20+ open flights from Ontario to San Francisco within the next 7 days for less than $100.

What days are nonstop flights available from Ontario to San Francisco?

You can find nonstop flights on the following days: Sunday, Monday, Tuesday, Thursday, Friday, Saturday.

How popular is this Ontario to San Francisco flight route?

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

7 flight departures from Ontario to San Francisco per day on average.
Early Morning (Midnight to 6am) - 57% of flight departures
Morning (6am - Noon) - 14% of flight departures
Afternoon (Noon - 6pm) - 29% of flight departures

How long is the flight from Ontario to San Francisco?

A quick flight from Ontario to San Francisco can take about 1h 32m. Frontier provides one of the quickest options available for as low as $38. The distance from Ontario to San Francisco is about 364 mi. All flights are typically nonstop.

What is the cheapest airline to fly from Ontario to San Francisco round-trip?

Flying on Frontier is currently your cheapest option to San Francisco, with prices starting at $38. You may be able to fly from Ontario to San Francisco for 75% less than the average price by searching for this airline.

What are the most popular airlines that fly from Ontario to San Francisco?

What are the most reliable airlines from 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 Ontario to San Francisco on time: Copa Airlines (86%), Emirates (83%), Air Canada (79%).

What are the cheapest flights from Ontario to San Francisco?

On average you can expect to pay $546 for a flight from Ontario to San Francisco. The cheapest flight overall is $26 while the most popular route, (Ontario - San Francisco) is currently priced at $48.

What does ONT to SFO mean?

ONT and SFO are unique codes to identify airports used in the aviation industry. They are defined by IATA (International Air Transport Association) and are commonly called IATA codes. ONT to SFO refers to a flight route from Ontario Airport to San Francisco Airport.

Alternative routes for Ontario to San Francisco

See prices for flight routes from nearby airports that may be better suited for you.

Top 8 airlines flying from Ontario to San Francisco

The chart below displays the airlines Cheapflights users traveling from Ontario to San Francisco choose most often. Cheapest and average prices are based on aggregated data from the past 12 months.
AirlineCheapestAverageFlexibilityOn-time
Spirit AirlinesCheapest$22Average$51FlexibilityNo cancel feeOn-time65%
Search Spirit Airlines flights
FrontierCheapest$34Average$88FlexibilityNo cancel feeOn-time62%
Search Frontier flights
JetBlueCheapest$48Average$69FlexibilityNo cancel feeOn-time62%
Search JetBlue flights
DeltaCheapest$64Average$148FlexibilityNo cancel feeOn-timeN/A
Search Delta flights
Breeze AirwaysCheapest$78Average$103FlexibilityNo cancel feeOn-timeN/A
Search Breeze Airways flights
Alaska AirlinesCheapest$83Average$148FlexibilityNo cancel feeOn-time75%
Search Alaska Airlines flights
United AirlinesCheapest$94Average$229FlexibilityNo cancel feeOn-time69%
Search United Airlines flights
American AirlinesCheapest$200Average$326FlexibilityNo cancel feeOn-time71%
Search American Airlines flights

Hourly flight availability from Ontario to San Francisco

See what time of day planes typically take off from Ontario to San Francisco
1%of flight departuresEarly morningMidnight to 6 am
44%of flight departuresMorning6 am to noon
23%of flight departuresAfternoonNoon to 6 pm
32%of flight departuresEvening6 pm to midnight
Midnight
6 AM
Noon
6 PM

Weekly flight availability from Ontario to San Francisco

See how many times per day planes take to the skies headed from Ontario to San Francisco
Sunday4daily flights
Monday7daily flights
Tuesday7daily flights
Wednesday7daily flights
Thursday8daily flights
Friday7daily flights
Saturday5daily flights

Fly with Cheapflights

What makes Cheapflights the go-to destination for all your flight needs

How does Cheapflights help users find flights from Ontario to San Francisco?

Cheapflights goes through 900+ travel sites to look for the best flight deals for flights from Ontario to San Francisco. Too many options? Cheapflights also provides filters for things like airlines, price ranges, and number of stops to help you make a decision easily.

Why should you use Cheapflights to find cheap flight tickets from Ontario to San Francisco?

Cheapflights taps into our reliable network of hundreds of airlines and travel agencies to find the best deals for flights from Ontario to San Francisco for you. Better yet — we are completely free to use.

Can Cheapflights find flights from Ontario to San Francisco with no change fees?

Yes! Cheapflights helps users easily find flights from Ontario to San Francisco with no change fees.

Can Cheapflights notify me if prices for flights from Ontario to San Francisco become cheaper?

Yes, Cheapflights has a feature called Price Alert, which essentially offers users the ability to be notified when flight prices change. Track prices for your flight to San Francisco from Ontario today and book when you’re ready!

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