Fremont

$66+ Cheap flights from Ontario (ONT) to Fremont, CA

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 6/13. Fares are subject to change and may not be available on all flights or dates of travel.
ONT — SFO
Jun 12 — Jun 191
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Cheapflights Tip: The best prices from Ontario to Fremont are usually found in August or October, booked 77 days in advance, depart on a Friday or Thursday and return on a Monday

Cheap flight deals from Ontario to Fremont

Cheapest flights from Ontario to Fremont
Explore the most affordable flight options available from Ontario to Fremont. Find the lowest fares from popular airlines and budget airlines, with prices last updated on May 13, 2026.

This Super.com deal was found by Cheapflights users on 5/12. 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 Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 8/258:33 pm
ONT
-
SFO
Nonstop1h 32m
Frontier
Sat 8/299:31 am
SFO
-
ONT
Nonstop1h 27m
Frontier
Deal found 5/12$106
This Super.com deal was found by Cheapflights users on 5/11. 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 Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 6/48:17 pm
ONT
-
SFO
Nonstop1h 38m
Frontier
Sun 6/79:34 am
SFO
-
ONT
Nonstop1h 32m
Frontier
Deal found 5/11$108
This Super.com deal was found by Cheapflights users on 5/12. 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 Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 6/38:17 pm
ONT
-
SFO
Nonstop1h 38m
Frontier
Fri 6/59:34 am
SFO
-
ONT
Nonstop1h 32m
Frontier
Deal found 5/12$109
This Frontier deal was found by Cheapflights users on 5/12. 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 8/318:33 pm
ONT
-
SFO
Nonstop1h 32m
Frontier
Thu 9/176:44 pm
SFO
-
ONT
Nonstop1h 33m
Frontier
Deal found 5/12$110
This Frontier deal was found by Cheapflights users on 5/12. 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.
Thu 10/12:26 pm
ONT
-
SFO
Nonstop1h 30m
Frontier
Mon 10/1212:31 pm
SFO
-
ONT
Nonstop1h 29m
Frontier
Deal found 5/12$111
This Super.com deal was found by Cheapflights users on 5/10. 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 Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 5/318:59 am
ONT
-
SFO
Nonstop1h 39m
Frontier
Wed 6/311:15 am
SFO
-
ONT
Nonstop1h 39m
Frontier
Deal found 5/10$112
This Super.com deal was found by Cheapflights users on 5/12. 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 Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 6/38:17 pm
ONT
-
SFO
Nonstop1h 38m
Frontier
Sat 6/69:34 am
SFO
-
ONT
Nonstop1h 32m
Frontier
Deal found 5/12$113
This Super.com deal was found by Cheapflights users on 5/10. 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 Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 5/308:59 am
ONT
-
SFO
Nonstop1h 39m
Frontier
Tue 6/211:15 am
SFO
-
ONT
Nonstop1h 39m
Frontier
Deal found 5/10$114
This Frontier deal was found by Cheapflights users on 5/9. 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.
Wed 7/298:39 pm
ONT
-
SFO
Nonstop1h 30m
Frontier
Wed 8/511:10 am
SFO
-
ONT
Nonstop1h 33m
Frontier
Deal found 5/9$115
This Super.com deal was found by Cheapflights users on 5/8. 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 Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 5/308:59 am
ONT
-
SFO
Nonstop1h 39m
Frontier
Mon 6/19:34 am
SFO
-
ONT
Nonstop1h 32m
Frontier
Deal found 5/8$116
This United Airlines deal was found by Cheapflights users on 5/12. 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.
Wed 6/101:50 pm
ONT
-
SFO
Nonstop1h 25m
United Airlines
Tue 6/169:00 pm
SFO
-
ONT
Nonstop1h 37m
United Airlines
Deal found 5/12$117
This Frontier deal was found by Cheapflights users on 5/9. 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.
Fri 5/298:59 am
ONT
-
SFO
Nonstop1h 39m
Frontier
Tue 6/211:15 am
SFO
-
ONT
Nonstop1h 39m
Frontier
Deal found 5/9$118

Find flight deals from Ontario to Fremont

Keep the following information in mind while searching for Ontario to Fremont flight deals. Data was last updated May 13, 2026.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$106
(Super.com)

One-way from

$66
(Super.com)

Popular in

February

Cheapest in

August

Average price

$157
Provider with most accurate pricing for Los Angeles-San Francisco flight deals.
Provider most trusted by Cheapflights users for Los Angeles-San Francisco flights.
From Ontario to Fremont
One-way flight from Ontario to Fremont
Highest demand for flights based on searches. 28% potential increase in price ($76 potential increase over avg. RT price).
Cheapest flight prices on average. 4% potential price decrease ($10 potential savings vs. average RT price).
Average for round-trip flights in May 2026

Cheapflights Fare Finder

 
Customize your flight search to find flights from Ontario to Fremont 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 May 13, 2026.
Use the filters below to find and compare flights from Ontario to Fremont that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

Cheapest round-trip
Quickest round-trip

OntarioSan Francisco

ONT - SFO

ONTSFO

Ontario

Wed 6/3

1:50 pm-3:15 pm

Nonstop1h 25m

San Francisco

Mon 6/8

10:40 am-12:12 pm

Nonstop1h 32m

$147

OntarioSan Francisco

ONT - SFO

ONTSFO

Ontario

Mon 6/1

6:00 pm-12:10 am

1 stop6h 10m

San Francisco

Wed 6/3

2:50 pm-9:45 pm

1 stop6h 55m

$177

OntarioSan Francisco

ONT - SFO

ONTSFO

Ontario

Mon 6/1

6:00 am-7:25 am

Nonstop1h 25m

San Francisco

Wed 6/3

10:40 am-12:12 pm

Nonstop1h 32m

$247

OntarioSan Francisco

ONT - SFO

ONTSFO

Ontario

Sat 6/6

1:40 pm-3:05 pm

Nonstop1h 25m

San Francisco

Mon 6/8

10:40 am-12:12 pm

Nonstop1h 32m

$247

OntarioSan Francisco

ONT - SFO

ONTSFO

Ontario

Sat 5/30

1:40 pm-3:05 pm

Nonstop1h 25m

San Francisco

Mon 6/1

9:00 pm-10:37 pm

Nonstop1h 37m

$349

OntarioSan Francisco

ONT - SFO

ONTSFO

Ontario

Tue 6/9

7:00 am-7:56 pm

1 stop12h 56m

San Francisco

Wed 6/17

7:20 am-11:51 pm

1 stop16h 31m

$368

OntarioSan Francisco

ONT - SFO

ONTSFO

Ontario

Thu 6/18

6:00 am-7:25 am

Nonstop1h 25m

San Francisco

Mon 6/22

10:40 am-12:12 pm

Nonstop1h 32m

$369

OntarioSan Francisco

ONT - SFO

ONTSFO

Ontario

Thu 6/11

1:50 pm-3:15 pm

Nonstop1h 25m

San Francisco

Mon 6/15

9:00 pm-10:37 pm

Nonstop1h 37m

$371

OntarioSan Francisco

ONT - SFO

ONTSFO

Ontario

Thu 6/18

5:15 am-11:20 am

2 stops6h 05m

San Francisco

Thu 6/18

12:30 pm-10:10 pm

2 stops9h 40m

$437

OntarioSan Francisco

ONT - SFO

ONTSFO

Ontario

Fri 5/29

6:00 am-7:25 am

Nonstop1h 25m

San Francisco

Sun 5/31

10:40 am-12:12 pm

Nonstop1h 32m

$449

Flights are sorted by cheapest round-trip flights first.

Deals found on 5/7

Showing 1-10 of 24 resultsSorted by cheapest first
1
2
3

Best time to book a flight from Ontario to Fremont

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

Cheapflights Insights

Everything you need to know about your flight from Ontario to Fremont

What is the cheapest time of day to fly from ONT to FR8?

Find hourly flight availability from Ontario to Fremont. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated May 13, 2026.

When flying from Ontario to Fremont, the time of day you fly usually plays a role in the price. Save by searching for a flight in the evening, which can drop the price by up to 25% versus a flight in the morning.

What is the cheapest day to fly from Ontario to Fremont?

Use this chart to determine the cheapest time to fly round-trip from Ontario to Fremont. Price data was last updated on May 9, 2026.

Travelers seeking maximum savings on their Ontario to Fremont flight should consider departing on Saturday at noon when fares are most often at their lowest. Sunday afternoons flights should be avoided if possible as fares are typically the most expensive at this time.

Weekly flight availability from Ontario to Fremont

Explore weekly flight availability from Ontario to Fremont. Discover flights operating on different days of the week, giving you the flexibility to choose a travel day that best fits your plans. Compare info to find the most convenient option for your journey. Data last updated May 13, 2026.

The most flights from ONT to FR8 are scheduled on a Monday (11 on average). You will have fewer flight options on Saturday, which is when the least amount of flights are scheduled (5 on average).

How much does it cost to fly round-trip from Ontario to Fremont?

Reviews of airlines servicing Fremont

Get insights into the airlines that provide service to Fremont. 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 Fremont. Reviews last updated May 13, 2026.
Get a feel of what it's like to fly with Southwest,Alaska Airlines, andUnited Airlines from Ontario to Fremont by reading reviews from past customers. Users have also rated airlines in terms of entertainment options, comfort, food, crew/service, and boarding process.

Crew

8.6

Food

7.0

Boarding

8.1

Entertainment

7.5

Overall

8.0

Comfort

8.0

Reviews

1 / 20
2.0
Mediocre

Dominic,Mar 2026

MCO - SMF

I had to try and sleep on the floor of the Austin airport. I spent 12 hours there. The airline policies were so poor, that a near violent argument broke out between the people in front of me and the flight attendants - making for a super stressful situation at 30,000 feet. Garbage airline choice by Kayak Garbage idea to book a flight with a layover. Next time I will pay for a quality booking myself, and somehow force the company to reimburse it.

Crew

8.6

Food

7.0

Boarding

8.1

Entertainment

7.5

Overall

8.0

Comfort

8.0

Reviews

1 / 20
2.0
Mediocre

Dominic,Mar 2026

MCO - SMF

I had to try and sleep on the floor of the Austin airport. I spent 12 hours there. The airline policies were so poor, that a near violent argument broke out between the people in front of me and the flight attendants - making for a super stressful situation at 30,000 feet. Garbage airline choice by Kayak Garbage idea to book a flight with a layover. Next time I will pay for a quality booking myself, and somehow force the company to reimburse it.

Crew

8.6

Food

7.0

Boarding

8.1

Entertainment

7.5

Overall

8.0

Comfort

8.0

Reviews

1 / 20
2.0
Mediocre

Dominic,Mar 2026

MCO - SMF

I had to try and sleep on the floor of the Austin airport. I spent 12 hours there. The airline policies were so poor, that a near violent argument broke out between the people in front of me and the flight attendants - making for a super stressful situation at 30,000 feet. Garbage airline choice by Kayak Garbage idea to book a flight with a layover. Next time I will pay for a quality booking myself, and somehow force the company to reimburse it.

Crew

8.6

Food

7.0

Boarding

8.1

Entertainment

7.5

Overall

8.0

Comfort

8.0

Reviews

1 / 20
2.0
Mediocre

Dominic,Mar 2026

MCO - SMF

I had to try and sleep on the floor of the Austin airport. I spent 12 hours there. The airline policies were so poor, that a near violent argument broke out between the people in front of me and the flight attendants - making for a super stressful situation at 30,000 feet. Garbage airline choice by Kayak Garbage idea to book a flight with a layover. Next time I will pay for a quality booking myself, and somehow force the company to reimburse it.

Crew

8.6

Food

7.0

Boarding

8.1

Entertainment

7.5

Overall

8.0

Comfort

8.0

Reviews

1 / 20
2.0
Mediocre

Dominic,Mar 2026

MCO - SMF

I had to try and sleep on the floor of the Austin airport. I spent 12 hours there. The airline policies were so poor, that a near violent argument broke out between the people in front of me and the flight attendants - making for a super stressful situation at 30,000 feet. Garbage airline choice by Kayak Garbage idea to book a flight with a layover. Next time I will pay for a quality booking myself, and somehow force the company to reimburse it.

Crew

8.6

Food

7.0

Boarding

8.1

Entertainment

7.5

Overall

8.0

Comfort

8.0

Reviews

1 / 20
2.0
Mediocre

Dominic,Mar 2026

MCO - SMF

I had to try and sleep on the floor of the Austin airport. I spent 12 hours there. The airline policies were so poor, that a near violent argument broke out between the people in front of me and the flight attendants - making for a super stressful situation at 30,000 feet. Garbage airline choice by Kayak Garbage idea to book a flight with a layover. Next time I will pay for a quality booking myself, and somehow force the company to reimburse it.

Related info for your journey

Find useful and relevant information for your journey from Ontario to Fremont. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.
  • What airport do you fly from for flights from Ontario to Fremont?

    Located just 3.1 mi from the city center, Ontario is the airport most travelers will use when flying to Fremont from Ontario. Booking flights from Ontario (ONT) to Fremont should be relatively easy as there are 8 daily outbound flights to Fremont from 5 different airlines.

  • How popular is this Ontario to Fremont flight route?

  • How long is the flight from Ontario to Fremont?

    Departing from Ontario to Fremont will take you 1h 25m. Airlines will cover a distance of 363 mi. Both multi-stop and nonstop flights can be found to your destination and back.

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

    $37 is the cheapest one-way deal found within the past few days, from Frontier. You may also be able to find cheap deals on United Airlines and Delta, with prices starting from $39 and $51, respectively.

  • What are the most reliable airlines from Ontario to Fremont?

    No one likes to see their flight delayed. When booking a flight from Ontario to Fremont consider choosing SkyWest Airlines (100%), Air Canada (75%) or Copa Airlines (72%) as they are the most reliable in getting you off to your destination on time.

  • What are the cheapest flights from Ontario to Fremont?

    Looking for the cheapest flight from Ontario to Fremont? While on average our users pay $651, our data indicates the cheapest price to be $33. The most popular route (Ontario - San Francisco), is priced around $56.

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

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

  • How can I find direct flights from Ontario to Fremont?

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

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

    Yes. Cheapflights offers flight deals from Ontario to Fremont by cabin class. In addition to browsing deals, you can also filter by cabin class on the search results page after making a search.

See more FAQs

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Alternative routes for Ontario to Fremont

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

Top 5 airlines flying from Ontario to Fremont

Discover the top 5 airlines that operate flights from Ontario to Fremont. 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 May 13, 2026.
AirlineCheapestAverageFlexibilityOn-time
FrontierCheapest$29Average$121FlexibilityNo cancel feeOn-time62%
United AirlinesCheapest$77Average$173FlexibilityNo cancel feeOn-time69%
Alaska AirlinesCheapest$78Average$167FlexibilityNo cancel feeOn-time75%
SouthwestCheapest$123Average$308FlexibilityNo cancel feeOn-time63%
JetBlueCheapest$153Average$169FlexibilityNo cancel feeOn-time62%

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