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Oakland

$106+ 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 4/29. Fares are subject to change and may not be available on all flights or dates of travel.
ONT — OAK
Apr 19 — Apr 261
Sun 4/19
Sun 4/26
1 adult, Economy
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1. Tell us where you want to go

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Cheapflights Tip: The best prices from Ontario to Oakland are usually found in September or August, booked 86 days in advance, depart on a Saturday or Wednesday 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 March 20, 2026.

This Southwest deal was found by Cheapflights users on 3/18. 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.
Wed 4/153:30 pm
ONT
-
OAK
Nonstop1h 20m
Southwest
Wed 4/226:00 am
OAK
-
ONT
Nonstop1h 20m
Southwest
Deal found 3/18$211
This Southwest deal was found by Cheapflights users on 3/17. 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.
Wed 4/155:50 pm
ONT
-
OAK
Nonstop1h 20m
Southwest
Mon 4/276:05 am
OAK
-
ONT
Nonstop1h 20m
Southwest
Deal found 3/17$221
This Southwest deal was found by Cheapflights users on 3/20. 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.
Thu 4/166:00 am
ONT
-
OAK
Nonstop1h 20m
Southwest
Thu 4/2310:50 am
OAK
-
ONT
Nonstop1h 20m
Southwest
Deal found 3/20$231
This Southwest deal was found by Cheapflights users on 3/20. 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.
Thu 4/166:00 pm
ONT
-
OAK
1 stop6h 05m
Southwest
Sat 4/1810:55 am
OAK
-
ONT
Nonstop1h 20m
Southwest
Deal found 3/20$241
This Southwest deal was found by Cheapflights users on 3/18. 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 4/143:30 pm
ONT
-
OAK
Nonstop1h 20m
Southwest
Sun 4/196:00 am
OAK
-
ONT
Nonstop1h 20m
Southwest
Deal found 3/18$245
This Southwest deal was found by Cheapflights users on 3/15. 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 4/73:30 pm
ONT
-
OAK
Nonstop1h 20m
Southwest
Mon 4/134:35 pm
OAK
-
ONT
2 stops6h 30m
Southwest
Deal found 3/15$246
This Southwest deal was found by Cheapflights users on 3/16. 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.
Mon 5/188:25 pm
ONT
-
OAK
Nonstop1h 20m
Southwest
Tue 5/196:10 am
OAK
-
ONT
2 stops5h 45m
Southwest
Deal found 3/16$250
This Southwest deal was found by Cheapflights users on 3/18. 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.
Mon 6/112:50 pm
ONT
-
OAK
2 stops7h 55m
Southwest
Tue 6/26:10 am
OAK
-
ONT
2 stops5h 45m
Southwest
Deal found 3/18$251
This Southwest deal was found by Cheapflights users on 3/18. 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.
Thu 5/76:00 am
ONT
-
OAK
Nonstop1h 20m
Southwest
Sun 5/1010:55 am
OAK
-
ONT
Nonstop1h 20m
Southwest
Deal found 3/18$255
This Southwest deal was found by Cheapflights users on 3/16. 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 4/76:30 am
ONT
-
OAK
2 stops6h 35m
Southwest
Wed 4/86:10 am
OAK
-
ONT
1 stop5h 25m
Southwest
Deal found 3/16$256

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 March 20, 2026.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$211
(Southwest)

One-way from

$106
(Southwest)

Popular in

January

Cheapest in

September

Average price

$299

Good round-trip deal

$279 or less

Good one-way deal

$141 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. 12% potential increase in price ($36 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 2% potential price decrease ($7 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in March 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 March 20, 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
Quickest round-trip

OntarioOakland

ONT - OAK

ONTOAK

Ontario

Thu 5/7

6:00 am-7:20 am

Nonstop1h 20m

Oakland

Sun 5/10

10:55 am-12:15 pm

Nonstop1h 20m

$255

OntarioOakland

ONT - OAK

ONTOAK

Ontario

Fri 4/17

5:05 pm-10:40 pm

1 stop5h 35m

Oakland

Sat 4/18

7:25 am-8:45 am

Nonstop1h 20m

$265

OntarioOakland

ONT - OAK

ONTOAK

Ontario

Thu 4/9

8:25 pm-9:45 pm

Nonstop1h 20m

Oakland

Sun 4/12

10:55 am-12:15 pm

Nonstop1h 20m

$265

OntarioOakland

ONT - OAK

ONTOAK

Ontario

Thu 5/7

8:10 am-2:00 pm

2 stops5h 50m

Oakland

Sun 5/17

6:00 am-7:20 am

Nonstop1h 20m

$270

OntarioOakland

ONT - OAK

ONTOAK

Ontario

Fri 7/10

11:05 am-12:20 pm

Nonstop1h 15m

Oakland

Mon 7/13

5:25 pm-12:05 am

2 stops6h 40m

$294

OntarioOakland

ONT - OAK

ONTOAK

Ontario

Sat 4/11

6:00 am-7:20 am

Nonstop1h 20m

Oakland

Sun 4/12

6:25 pm-11:35 pm

2 stops5h 10m

$314

OntarioOakland

ONT - OAK

ONTOAK

Ontario

Thu 4/2

5:25 am-9:25 am

1 stop4h 00m

Oakland

Mon 4/6

6:00 am-7:20 am

Nonstop1h 20m

$315

OntarioOakland

ONT - OAK

ONTOAK

Ontario

Tue 6/16

10:20 am-11:40 am

Nonstop1h 20m

Oakland

Fri 7/10

5:25 pm-12:05 am

2 stops6h 40m

$338

OntarioOakland

ONT - OAK

ONTOAK

Ontario

Mon 3/30

7:55 pm-9:20 pm

Nonstop1h 25m

Oakland

Sun 4/12

10:55 am-12:15 pm

Nonstop1h 20m

$339
Cheapest one-way
Quickest one-way

OntarioOakland

ONT - OAK

ONTOAK

Ontario

Wed 4/29

5:55 am-7:15 am

Nonstop1h 20m

$106

Flights are sorted by cheapest round-trip flights first.

Deals found on 3/18

Showing 1-10 of 18 resultsSorted by cheapest first
1
2

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 March.
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?

Use this chart to determine the optimal time to book a round-trip flight from Ontario to Oakland. Price data was last updated on March 13, 2026.

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 84 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, May is the cheapest month in which you can book a flight from Ontario to Oakland, California (average of $28). Flying from Ontario to Oakland, California in November is currently the most expensive (average of $62). 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 March 20, 2026.

Unlike in the morning, when flights are generally more expensive, you can save up to 19% on flights from Ontario to Oakland, California by exploring options for tickets in the evening.

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 March 14, 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 afternoons flights should be avoided if possible as fares are typically the most expensive at this time.

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 March 20, 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
4,324 reviews

Comfort

8.0

Food

7.0

Entertainment

7.5

Boarding

8.1

Crew

8.6

Overall

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.
Southwest
8.0
Very good
4,324 reviews
Southwest
8.0
Very good
4,324 reviews

Comfort

8.0

Food

7.0

Entertainment

7.5

Boarding

8.1

Crew

8.6

Overall

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.
Frontier
5.7
Fair
3,024 reviews
Southwest
8.0
Very good
4,324 reviews

Comfort

8.0

Food

7.0

Entertainment

7.5

Boarding

8.1

Crew

8.6

Overall

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 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 are 2 flights 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 13 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 20m. 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 $52, 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 $114. Frontier is 79% 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?

    $48 is the cheapest one-way deal found within the past few days, from Southwest. You may also be able to find cheap deals on Frontier and United Airlines, with prices starting from $49 and $58, respectively.

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

    The cheapest flight price from Ontario to Oakland, California is $111. On average you can expect to pay $279. The most popular route, (Ontario - Oakland), can usually be booked for $211.

  • 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, May is the cheapest month in which you can book a flight from Ontario to Oakland, California (average of $28). Flying from Ontario to Oakland, California in November is currently the most expensive (average of $62). 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 March 20, 2026.
AirlineCheapestAverageFlexibilityOn-time
FrontierCheapest$52Average$105FlexibilityNo cancel feeOn-time62%
SouthwestCheapest$114Average$273FlexibilityNo cancel feeOn-time63%

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