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Oakland

$78+ Cheap flights from Ontario to Oakland, CA (ONT - OAK)

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 9/3. Fares are subject to change and may not be available on all flights or dates of travel.
ONT — OAK
Sep 1 — Sep 81
Tue 9/1
Tue 9/8
1 adult, Economy
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Find cheap flights from Ontario to Oakland with Cheapflights

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Cheapflights Tip: The best prices from Ontario to Oakland are usually found in October or September, booked 69 days in advance, depart on a Thursday or Saturday and return on a Tuesday

Cheap flight deals from Ontario to Oakland

Cheapest flights from Ontario to Oakland
Explore the most affordable flight options available from Ontario to Oakland. Find the lowest fares from popular airlines and budget airlines, with prices last updated on August 2, 2026.

This Frontier deal was found by Cheapflights users on 7/30. 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 8/2711:15 am
ONT
-
OAK
1 stop8h 27m
Frontier
Mon 8/3112:13 pm
OAK
-
ONT
1 stop9h 14m
Frontier
Deal found 7/30$156
This Frontier deal was found by Cheapflights users on 7/30. 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 8/273:40 pm
ONT
-
OAK
1 stop4h 02m
Frontier
Thu 9/312:13 pm
OAK
-
ONT
1 stop4h 09m
Frontier
Deal found 7/30$157
This Frontier deal was found by Cheapflights users on 7/30. 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 8/203:40 pm
ONT
-
OAK
1 stop4h 02m
Frontier
Mon 8/2412:13 pm
OAK
-
ONT
1 stop9h 14m
Frontier
Deal found 7/30$158
This Frontier deal was found by Cheapflights users on 8/2. 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 8/283:40 pm
ONT
-
OAK
1 stop4h 02m
Frontier
Tue 9/112:13 pm
OAK
-
ONT
1 stop3h 36m
Frontier
Deal found 8/2$177
This Frontier deal was found by Cheapflights users on 7/31. 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 9/148:00 am
ONT
-
OAK
1 stop9h 56m
Frontier
Mon 9/2110:17 am
OAK
-
ONT
1 stop6h 42m
Frontier
Deal found 7/31$178
This Frontier deal was found by Cheapflights users on 7/31. 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 11/162:58 pm
ONT
-
OAK
1 stop4h 46m
Frontier
Tue 11/247:13 pm
OAK
-
ONT
Nonstop1h 20m
Frontier
Deal found 7/31$188
This Kiwi.com deal was found by Cheapflights users on 7/30. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 9/138:24 pm
ONT
-
OAK
1 stop12h 58m
Frontier
Sun 9/206:51 pm
OAK
-
ONT
1 stop12h 13m
Frontier
Deal found 7/30$195
This Kiwi.com deal was found by Cheapflights users on 7/29. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 9/258:00 am
ONT
-
OAK
1 stop9h 56m
Frontier
Sun 9/276:51 pm
OAK
-
ONT
1 stop12h 13m
Frontier
Deal found 7/29$196
This Kiwi.com deal was found by Cheapflights users on 8/1. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 10/92:58 pm
ONT
-
OAK
1 stop4h 46m
Frontier
Sun 10/118:39 pm
OAK
-
ONT
1 stop13h 42m
Frontier
Deal found 8/1$197
This Frontier deal was found by Cheapflights users on 7/31. 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 9/33:40 pm
ONT
-
OAK
1 stop4h 02m
Frontier
Sat 9/512:13 pm
OAK
-
ONT
1 stop3h 36m
Frontier
Deal found 7/31$198
This Kiwi.com deal was found by Cheapflights users on 7/31. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 9/278:24 pm
ONT
-
OAK
1 stop12h 58m
Frontier
Mon 9/286:51 pm
OAK
-
ONT
1 stop14h 18m
Frontier
Deal found 7/31$200

Find flight deals from Ontario to Oakland

Discover tips and strategies to find the most affordable flight options for your journey from Ontario (ONT) to Oakland (OAK). 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 August 2, 2026.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$156
(Frontier)

One-way from

$78
(Frontier)

Popular in

July

Cheapest in

October

Average price

$319

Good round-trip deal

$225 or less

Good one-way deal

$109 or less
Provider with most accurate pricing for Ontario-Oakland flight deals.
Search Deals
Provider most trusted by Cheapflights users for Ontario-Oakland flights.
Search Deals
From Ontario to Oakland
Search Deals
One-way flight from Ontario to Oakland
Search Deals
Highest demand for flights based on searches. 11% potential increase in price ($37 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 1% potential price decrease ($5 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in August 2026
Search Deals
Price to beat on a round-trip flight from Ontario to Oakland.
Search Deals
Price to beat on a one-way flight from Ontario to Oakland.
Search Deals

Cheapflights Fare Finder

 
Customize your flight search to find flights from Ontario to Oakland 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 August 2, 2026.
Use the filters below to find and compare flights from Ontario to Oakland that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

Cheapest round-trip

OntarioOakland

ONT - OAK

ONTOAK

Ontario

Sat 9/5

6:00 am-7:15 am

Nonstop1h 15m

Oakland

Tue 9/8

8:30 pm-10:00 pm

Nonstop1h 30m

$227
Quickest round-trip

OntarioOakland

ONT - OAK

ONTOAK

Ontario

Mon 9/14

4:00 pm-5:20 pm

Nonstop1h 20m

Oakland

Mon 9/21

10:30 am-11:50 am

Nonstop1h 20m

$235

OntarioOakland

ONT - OAK

ONTOAK

Ontario

Thu 8/27

8:00 pm-9:15 pm

Nonstop1h 15m

Oakland

Sat 8/29

6:40 am-8:05 am

Nonstop1h 25m

$235

OntarioOakland

ONT - OAK

ONTOAK

Ontario

Tue 9/15

9:40 am-4:00 pm

1 stop6h 20m

Oakland

Tue 9/22

2:40 pm-4:00 pm

Nonstop1h 20m

$245

OntarioOakland

ONT - OAK

ONTOAK

Ontario

Fri 8/21

4:00 pm-5:20 pm

Nonstop1h 20m

Oakland

Sat 8/22

6:25 pm-7:45 pm

Nonstop1h 20m

$248

OntarioOakland

ONT - OAK

ONTOAK

Ontario

Fri 9/25

8:00 pm-9:20 pm

Nonstop1h 20m

Oakland

Sun 9/27

11:50 am-1:10 pm

Nonstop1h 20m

$298

OntarioOakland

ONT - OAK

ONTOAK

Ontario

Fri 9/18

6:30 am-7:55 am

Nonstop1h 25m

Oakland

Sun 9/20

7:10 am-8:30 am

Nonstop1h 20m

$298

OntarioOakland

ONT - OAK

ONTOAK

Ontario

Fri 10/9

6:10 am-7:30 am

Nonstop1h 20m

Oakland

Sun 10/11

5:20 pm-6:40 pm

Nonstop1h 20m

$332

OntarioOakland

ONT - OAK

ONTOAK

Ontario

Fri 9/18

4:27 pm-11:06 am

2 stops18h 39m

Oakland

Sun 9/20

5:10 pm-3:47 pm

2 stops22h 37m

$349

OntarioOakland

ONT - OAK

ONTOAK

Ontario

Tue 8/18

8:35 am-2:45 pm

2 stops6h 10m

Oakland

Fri 8/21

7:55 pm-9:15 pm

Nonstop1h 20m

$353

Flights are sorted by cheapest round-trip flights first.

Deals found on 8/1

Showing 1-10 of 22 resultsSorted by cheapest first
1
2
3

Compare providers for flights from Ontario to Oakland

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 Ontario to Oakland in August.
ProviderPrice AccuracyTrust Score*
ExpediaPrice Accuracy1 starTrust Score*3 stars
FlightHubPrice Accuracy3 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 Ontario-Oakland, California flights, users find the pricing of FlightHub to be most consistent on Cheapflights vs. FlightHub Users can find the same prices on Ontario-Oakland, California flight deals on Cheapflights vs. FlightHub >95% of the time. Price accuracy is based on data collected from Ontario-Oakland, California flight searches over the past month and is updated monthly.
  • Most trusted provider: When it comes to deals on Ontario-Oakland, California 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 Ontario-Oakland, California 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 Ontario to Oakland

Have a flexible travel schedule? Discover the best time to fly to Oakland 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 Oakland

How far ahead should I book a flight from Ontario to Oakland, California?

The price you pay for your flight from Ontario to Oakland, California may vary depending on when you book. For the best chance of a lower fare, look to book 68 days in advance of your trip. Fares are likely to increase a fortnight or so before your departure date.

What is the cheapest month to book a flight from Ontario to Oakland, California?

Currently, October is the cheapest month in which you can book a flight from Ontario to Oakland, California (average of $219). Flying from Ontario to Oakland, California in July is currently the most expensive (average of $349). 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 ONT to OAK?

Find hourly flight availability from Ontario to Oakland. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated August 2, 2026.

Unlike in the morning, when flights are generally more expensive, you can save up to 27% on flights from Ontario to Oakland, California by exploring options for tickets at noon.

What is the cheapest day to fly from Ontario to Oakland, California?

Use this chart to determine the cheapest time to fly round-trip from Ontario to Oakland. Price data was last updated on July 25, 2026.

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

How much does it cost to fly round-trip from Ontario to Oakland, California?

Airfare is below average for this route at the moment.

Ontario to Oakland, California flights typically cost between $207 and $366 in August.
The cheapest round-trip price found within the last 5 days was $156 on Frontier (Aug 27-Aug 31).

The best insider tips for Ontario to Oakland flights

AI-powered summary based on content written by travel experts. AI can make mistakes.
Cheapflights partnered with top experts to bring you the best recommendations for your Ontario to Oakland trip
Our travel experts
Bill Fink

Bill Fink

Expert on ONT and OAK

Bill is an award-winning travel writer with extensive credits covering airlines and the aviation industry for publications including AARP, AFAR, The Points Guy and Yahoo. Based in Portland, Oregon, Bill has traveled to more than 75 countries - and been late for his flight in most of them. He once achieved top-level frequent flier status for all of American, Delta and United Airlines during a single year.

Read more

Reviews of airlines servicing Oakland

Get insights into the airlines that provide service to Oakland. 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 Oakland. Reviews last updated August 2, 2026.
Peruse reviews from past customers who have flown with Southwest and Frontier from Ontario to Oakland to help guide your decision. You can also see how each airline stacks up in terms of entertainment options, comfort, food, crew/service, and boarding process.
Southwest
8.0
Very good
4,227 reviews

Boarding

8.1

Crew

8.6

Comfort

8.0

Overall

8.0

Entertainment

7.5

Food

7.0

Reviews

1 / 20
8.0
Excellent

Walter,Aug 2025

OAK - SAN

Dozens of flights and I've never seen a row's beverages forgotten. I even went back and asked the attendant to check on them and nothing. I really hope it didn't have something to do with the Black mother with her kid in the row. Otherwise it was a typical Southwest flight, rapid boarding, tolerable leg room.
Southwest
8.0
Very good
4,227 reviews
Southwest
8.0
Very good
4,227 reviews

Boarding

8.1

Crew

8.6

Comfort

8.0

Overall

8.0

Entertainment

7.5

Food

7.0

Reviews

1 / 20
8.0
Excellent

Walter,Aug 2025

OAK - SAN

Dozens of flights and I've never seen a row's beverages forgotten. I even went back and asked the attendant to check on them and nothing. I really hope it didn't have something to do with the Black mother with her kid in the row. Otherwise it was a typical Southwest flight, rapid boarding, tolerable leg room.
Frontier
5.6
Fair
2,739 reviews
Southwest
8.0
Very good
4,227 reviews

Boarding

8.1

Crew

8.6

Comfort

8.0

Overall

8.0

Entertainment

7.5

Food

7.0

Reviews

1 / 20
8.0
Excellent

Walter,Aug 2025

OAK - SAN

Dozens of flights and I've never seen a row's beverages forgotten. I even went back and asked the attendant to check on them and nothing. I really hope it didn't have something to do with the Black mother with her kid in the row. Otherwise it was a typical Southwest flight, rapid boarding, tolerable leg room.

Related info for your journey

Find useful and relevant information for your journey from Ontario to Oakland. 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 Ontario to Oakland?

    If you wish to fly to Oakland from Ontario, then you need to book flights from Ontario to Oakland. There is 1 flight from Ontario (ONT) to Oakland (OAK) per day to choose from. Flights to Oakland from Ontario are available from 2 different airlines, which means you should have some options if you want to compare airfare deals. 1h 15m is how long a nonstop flight from Ontario to Oakland typically takes.

  • How popular is this Ontario to Oakland, California flight route?

    The Ontario to Oakland flight path was viewed by 10 users in the past month. Keep an eye out for changes in search interest prior to high and low season.

  • How long is the flight from Ontario to Oakland, California?

    Southwest can get you from Ontario to Oakland, California in just under 1h 15m. Your travel time will be generally consistent. Airlines will cover a distance of 361 mi. All flights are typically nonstop.

  • What are the cheapest airlines flying from Ontario to Oakland, California round-trip?

    Currently priced at $33, Frontier will fly you from Ontario to Oakland, California and back. In addition to Frontier, many other airlines offer competitively priced options for your trip. Check Cheapflights for deals on Southwest for as low as $147. Frontier is 88% cheaper than the average price of flights available within the next 90 days to this destination.

  • What are the cheapest airlines to fly from Ontario to Oakland, California one-way?

    $40 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 Southwest, with prices starting from $58 and $68, respectively.

  • What are the cheapest flights from Ontario to Oakland, California?

    The cheapest flight price from Ontario to Oakland, California is $88. On average you can expect to pay $287. The most popular route, (Ontario - Oakland), can usually be booked for $219.

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

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

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

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

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

    Yes. Cheapflights offers flight deals from Ontario to Oakland 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 Ontario to Oakland, California?

    Currently, October is the cheapest month in which you can book a flight from Ontario to Oakland, California (average of $219). Flying from Ontario to Oakland, California in July is currently the most expensive (average of $349). 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 2 airlines flying from Ontario to Oakland

Discover the top 2 airlines that operate flights from Ontario to Oakland. 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 August 2, 2026.
AirlineCheapestAverageFlexibilityOn-time
FrontierCheapest$33Average$105FlexibilityNo cancel feeOn-time62%
SouthwestCheapest$147Average$301FlexibilityNo cancel feeOn-time63%

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