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$29+ Cheap flights from San Francisco to Ontario (SFO - ONT)

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 3/6. Fares are subject to change and may not be available on all flights or dates of travel.
SFO — ONT
Jan 28 — Feb 41
Tue 1/28
Tue 2/4
1 adult, Economy
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The best prices from San Francisco to Ontario are usually found in May or July, booked 89 days in advance, depart on a Wednesday or Monday and return on a Friday

Cheap flight deals from San Francisco to Ontario

Discover tips and strategies to find the most affordable flight options for your journey from San Francisco (SFO) to Ontario (ONT). Learn about various techniques such as flexible date searches, comparing prices across and setting up price alerts. Use these methods to find the cheapest flights available for your travel needs. Data last updated January 23, 2025.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$53
(Frontier)

One-way from

$29
(Cheapflightsfares)

Popular in

December

Cheapest in

May

Average price

$199

Good round-trip deal

$57 or less

Good one-way deal

$51 or less
Provider with most accurate pricing for San Francisco-Ontario flight deals.
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Provider most trusted by Cheapflights users for San Francisco-Ontario flights.
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From San Francisco to Ontario
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One-way flight from San Francisco to Ontario
Search Deals
Highest demand for flights based on searches. 29% potential increase in price ($58 potential increase over avg. RT price).
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Cheapest flight prices on average. 7% potential price decrease ($9 potential savings vs. average RT price).
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Average for round-trip flights in January 2025
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Price to beat on a round-trip flight from San Francisco to Ontario.
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Price to beat on a one-way flight from San Francisco to Ontario.
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Find flight deals from San Francisco to Ontario

Cheapest flights from San Francisco to Ontario
Explore the most affordable flight options available from San Francisco to Ontario. Find the lowest fares from popular airlines and budget airlines, with prices last updated on January 23, 2025.

This Frontier deal was found by Cheapflights users on 1/23. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 5/58:34 amSFO - ONT
Nonstop1h 28mFrontier
Sat 5/108:23 amONT - SFO
Nonstop1h 38mFrontier
Deal found 1/23$54
This United Airlines deal was found by Cheapflights users on 1/23. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 3/17:10 pmSFO - ONT
Nonstop1h 30mUnited Airlines
Sun 3/26:00 amONT - SFO
Nonstop1h 29mUnited Airlines
Deal found 1/23$57
This American Airlines deal was found by Cheapflights users on 1/23. 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.
Tue 1/289:15 amSFO - ONT
1 stop6h 14mAmerican Airlines
Wed 1/2912:48 pmONT - SFO
1 stop6h 11mAmerican Airlines
Deal found 1/23$199
This Southwest deal was found by Cheapflights users on 1/22. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 1/286:05 amSFO - ONT
2 stops7h 20mSouthwest
Tue 1/286:35 pmONT - SFO
1 stop3h 40mSouthwest
Deal found 1/22$212

Find flights from San Francisco to Ontario within your budget

Customize your flight search to find flights from San Francisco to Ontario 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 January 23, 2025.

Fly from

Any airport

Fly to

Any airport

Route

Depart

Return

Price

San FranciscoOntario

SFO - ONT

SFOONT

San Francisco

Mon 5/5

8:34 am-10:02 am

Nonstop1h 28m

Ontario

Sat 5/10

8:23 am-10:01 am

Nonstop1h 38m

$54

San FranciscoOntario

SFO - ONT

SFOONT

San Francisco

Sat 3/1

7:10 pm-8:40 pm

Nonstop1h 30m

Ontario

Sun 3/2

6:00 am-7:29 am

Nonstop1h 29m

$57

San FranciscoOntario

SFO - ONT

SFOONT

San Francisco

Sun 2/2

5:55 am-12:06 pm

1 stop6h 11m

Ontario

Wed 2/5

6:10 am-12:30 pm

1 stop6h 20m

$199

San FranciscoOntario

SFO - ONT

SFOONT

San Francisco

Sun 2/9

11:05 am-10:20 pm

2 stops11h 15m

Ontario

Fri 2/14

4:55 pm-11:45 pm

1 stop6h 50m

$212

San FranciscoOntario

SFO - ONT

SFOONT

San Francisco

Thu 3/6

9:15 pm-10:45 pm

Nonstop1h 30m

$29

San FranciscoOntario

SFO - ONT

SFOONT

San Francisco

Thu 3/20

8:16 am-9:44 am

Nonstop1h 28m

$30

San FranciscoOntario

SFO - ONT

SFOONT

San Francisco

Sun 3/9

5:00 am-9:50 am

1 stop4h 50m

$76

San FranciscoOntario

SFO - ONT

SFOONT

San Francisco

Mon 2/3

9:15 am-3:29 pm

1 stop6h 14m

$100

San FranciscoOntario

SFO - ONT

SFOONT

San Francisco

Tue 2/4

7:55 pm-10:34 am

1 stop14h 39m

$137

Flights are sorted by cheapest round-trip flights first.

Deals found on 1/23

Compare providers for flights from San Francisco to Ontario

Provider information is updated monthly. Please note that these providers often have deals for this flight, but the availability may vary on a day-by-day basis on Cheapflights.
Use the table below to compare price accuracy, trust ratings, and cancellation policies for each provider offering flight deals from San Francisco to Ontario in January.
ProviderPrice AccuracyTrust Score*
ExpediaPrice Accuracy1 starTrust Score*3 stars
eDreamsPrice Accuracy3 starsTrust Score*3 stars
FlightHubPrice Accuracy3 starsTrust Score*3 stars
CheapflightsfaresPrice Accuracy3 starsTrust Score*1 star
PricelinePrice Accuracy2 starsTrust Score*3 stars
Kiwi.comPrice Accuracy3 starsTrust Score*3 stars
MytripPrice Accuracy3 starsTrust Score*3 stars
Justfly.comPrice Accuracy3 starsTrust Score*3 stars
CheapOairPrice Accuracy2 starsTrust Score*2 stars
Trip.comPrice Accuracy2 starsTrust Score*3 stars

*The Trust Score is based on feedback from users after their booking experience. It measures overall satisfaction, helping us identify issues like hidden fees, problems during the ticketing process, and the quality of customer service. This score is our best indicator of the provider's quality and reliability.

  • Most accurate provider: When it comes to deals on San Francisco-Ontario flights, users find the pricing of FlightHub to be most consistent on Cheapflights vs. FlightHub Users can find the same prices on San Francisco-Ontario flight deals on Cheapflights vs. FlightHub >95% of the time. Price accuracy is based on data collected from San Francisco-Ontario flight searches over the past month and is updated monthly.
  • Most trusted provider: When it comes to deals on San Francisco-Ontario flights, Cheapflights users trust FlightHub the most. FlightHub has received a user feedback score of 3 out of 3 stars (3 being the best), meaning they have been trusted the most by Cheapflights users looking for San Francisco-Ontario flight deals. Provider user feedback score is based on Cheapflights searches over the past month and is updated monthly.

Best time to book a flight from San Francisco to Ontario

Have a flexible travel schedule? Discover the best time to fly to Ontario from San Francisco 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.

Travel insights for flights from San Francisco to Ontario

Get recent, data-driven insights about flights from San Francisco to Ontario including ideal travel times, pricing trends, and more.

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

Use this chart to determine the optimal time to book a round-trip flight from San Francisco to Ontario. Price data was last updated on January 17, 2025.

Booking 55 days in advance of your planned departure date is, on average, the best time to get cheap flights from San Francisco to Ontario. The general trend is that the closer you book to the departure date, the more expensive your flight will be.

What is the cheapest month to book a flight from San Francisco to Ontario?

Currently, August is the cheapest month in which you can book a flight from San Francisco to Ontario (average of $246). Flying from San Francisco to Ontario in March is currently the most expensive (average of $310). 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 SFO to ONT?

Find hourly flight availability from San Francisco to Ontario. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated January 23, 2025.

Unlike in the evening, when flights are generally more expensive, you can save up to 50% on flights from San Francisco to Ontario by exploring options for tickets at noon.

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

Use this chart to determine the cheapest time to fly round-trip from San Francisco to Ontario. Price data was last updated on January 21, 2025.

Travelers seeking maximum savings on their San Francisco to Ontario flight should consider departing on Tuesday afternoons when fares are most often at their lowest. Thursday evenings flights should be avoided if possible as fares are typically the most expensive at this time.

Rainfall in Ontario by month

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

In terms of precipitation, rainfall in Ontario ranges from 0.1 - 3.4 inches per month. February is typically the wettest month, when rainfall can reach 3.4 in. June is typically the driest time to visit Ontario when rainfall is around 0.1 in.

Temperature in Ontario by month

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

If weather is an important factor for your trip to Ontario, use this chart to help with planning. For those seeking warmer temperatures, August is the ideal time of year to visit, when temperatures reach an average of 78.8 F. Travelers looking to avoid the cold should look outside of December, when temperatures are typically at their lowest (around 53.6 F).

Reviews of airlines servicing Ontario

Get insights into the airlines that provide service to Ontario. 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 Ontario. Reviews last updated January 23, 2025.
Get a feel of what it's like to fly with Frontier, United Airlines and Southwest from San Francisco to Ontario by reading reviews from past customers. Users have also rated airlines in terms of entertainment options, comfort, food, crew/service, and boarding process.
Southwest
8.1
Very good
4,647 reviews

Overall

8.1

Entertainment

7.7

Crew

8.7

Food

7.2

Boarding

8.2

Comfort

8.1

Reviews

1 / 10

No issues. I needed pre boarding and I was able to get it without issue

Southwest
8.1
Very good
4,647 reviews
Southwest
8.1
Very good
4,647 reviews

Overall

8.1

Entertainment

7.7

Crew

8.7

Food

7.2

Boarding

8.2

Comfort

8.1

Reviews

1 / 10

No issues. I needed pre boarding and I was able to get it without issue

Alaska Airlines
8.0
Very good
9,699 reviews
Southwest
8.1
Very good
4,647 reviews

Overall

8.1

Entertainment

7.7

Crew

8.7

Food

7.2

Boarding

8.2

Comfort

8.1

Reviews

1 / 10

No issues. I needed pre boarding and I was able to get it without issue

Delta
8.0
Very good
8,508 reviews
Southwest
8.1
Very good
4,647 reviews

Overall

8.1

Entertainment

7.7

Crew

8.7

Food

7.2

Boarding

8.2

Comfort

8.1

Reviews

1 / 10

No issues. I needed pre boarding and I was able to get it without issue

United Airlines
7.4
Good
8,970 reviews
Southwest
8.1
Very good
4,647 reviews

Overall

8.1

Entertainment

7.7

Crew

8.7

Food

7.2

Boarding

8.2

Comfort

8.1

Reviews

1 / 10

No issues. I needed pre boarding and I was able to get it without issue

American Airlines
7.2
Good
10,000 reviews
Southwest
8.1
Very good
4,647 reviews

Overall

8.1

Entertainment

7.7

Crew

8.7

Food

7.2

Boarding

8.2

Comfort

8.1

Reviews

1 / 10

No issues. I needed pre boarding and I was able to get it without issue

Related info for your journey

Find useful and relevant information for your journey from San Francisco to Ontario. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.

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

    Ontario is the airport most travelers will use when flying to Ontario from San Francisco. Booking flights from San Francisco (SFO) to Ontario (ONT) should be relatively easy as there are 5 daily flights to Ontario from 6 different airlines. 1h 22m is how long a flight from San Francisco to Ontario will take if you book a nonstop flight.

  • How popular is this San Francisco to Ontario flight route?

    Within the past month, 105 users have taken a look at flights from San Francisco to Ontario.

  • What are the cheapest airlines flying from San Francisco to Ontario round-trip?

    Flying on Frontier is currently your cheapest option to Ontario, with prices starting at $53. Additional round-trip tickets that might be worth considering are offered by United Airlines and American Airlines, with the lowest prices starting at $57 and $199, respectively. You may be able to fly from San Francisco to Ontario for 61% less than the average price by searching for these airlines.

  • What are the cheapest airlines to fly from San Francisco to Ontario one-way?

    To fly one-way, consider booking your trip with Frontier, which is currently one of the cheapest options available, starting at $29. United Airlines flights start at $59 while deals on Southwest start at $88 one-way.

  • What are the most reliable airlines from San Francisco to Ontario?

    No one likes to see their flight delayed. When booking a flight from San Francisco to Ontario consider choosing United Airlines (87%), Emirates (81%) or SkyWest Airlines (81%) as they are the most reliable in getting you off to your destination on time.

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

    On average you can expect to pay $175 for a flight from San Francisco to Ontario. The cheapest flight overall is $19 while the most popular route, (San Francisco - Ontario) is currently priced at $38.

  • Can I find deals for flights from San Francisco to Ontario that include hotel bookings?

    Yes. In addition to deals on San Francisco to Ontario flights, Cheapflights offers vacation packages that include both flights and hotel.

  • How can I find direct flights from San Francisco to Ontario?

    After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from San Francisco to Ontario.

  • Can I find deals for business class flights from San Francisco to Ontario?

    Yes. Cheapflights offers flight deals from San Francisco to Ontario 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 San Francisco to Ontario?

    Currently, August is the cheapest month in which you can book a flight from San Francisco to Ontario (average of $246). Flying from San Francisco to Ontario in March is currently the most expensive (average of $310). 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

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Top 6 airlines flying from San Francisco to Ontario

Discover the top 6 airlines that operate flights from San Francisco to Ontario. 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 January 23, 2025.
AirlineCheapestAverageFlexibilityOn-time
Spirit AirlinesCheapest$32Average$123FlexibilityNo cancel feeOn-time65%
FrontierCheapest$39Average$95FlexibilityNo cancel feeOn-time62%
DeltaCheapest$45Average$124FlexibilityNo cancel feeOn-timeN/A
Alaska AirlinesCheapest$55Average$150FlexibilityNo cancel feeOn-time75%
Breeze AirwaysCheapest$78Average$129FlexibilityNo cancel feeOn-timeN/A
United AirlinesCheapest$124Average$263FlexibilityNo cancel feeOn-time69%
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