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$39+ Cheap flights from Oakland, CA to Ontario (OAK - 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 10/20. Fares are subject to change and may not be available on all flights or dates of travel.
OAK — ONT
ago. 19 — ago. 261
mar. 8/19
mar. 8/26
1 adult, Economy
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Cheapflights Tip: The best prices from Oakland to Ontario are usually found in August or September, booked 62 days in advance, depart on a Sunday or Wednesday and return on a Saturday

Cheap flight deals from Oakland to Ontario

Discover tips and strategies to find the most affordable flight options for your journey from Oakland (OAK) 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 agosto 14, 2025.

Round-trip from

$77
(Southwest)

One-way from

$39
(Southwest)

Popular in

February

Cheapest in

August

Average price

$205

Good round-trip deal

$124 or less

Good one-way deal

$48 or less
From Oakland to Ontario
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One-way flight from Oakland to Ontario
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Highest demand for flights based on searches. 5% potential increase in price ($14 potential increase over avg. RT price).
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Cheapest flight prices on average. 1% potential price decrease ($4 potential savings vs. average RT price).
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Average for round-trip flights in August 2025
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Price to beat on a round-trip flight from Oakland to Ontario.
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Price to beat on a one-way flight from Oakland to Ontario.
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Find flight deals from Oakland to Ontario

Cheapest flights from Oakland to Ontario
Explore the most affordable flight options available from Oakland to Ontario. Find the lowest fares from popular airlines and budget airlines, with prices last updated on agosto 14, 2025.

This Southwest deal was found by Cheapflights users on 8/13. 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.
mié. 9/109:55 amOAK - ONT
Nonstop1h 20mSouthwest
mié. 9/178:15 amONT - OAK
Nonstop1h 20mSouthwest
Deal found 8/13$77
This Southwest deal was found by Cheapflights users on 8/14. 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.
jue. 9/258:30 amOAK - ONT
Nonstop1h 20mSouthwest
dom. 9/289:20 amONT - OAK
Nonstop1h 20mSouthwest
Deal found 8/14$114
This Southwest deal was found by Cheapflights users on 8/14. 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.
mié. 9/1712:10 pmOAK - ONT
1 stop4h 35mSouthwest
jue. 9/185:50 amONT - OAK
Nonstop1h 20mSouthwest
Deal found 8/14$124
This Southwest deal was found by Cheapflights users on 8/12. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
vie. 10/245:45 amOAK - ONT
Nonstop1h 20mSouthwest
lun. 10/273:05 pmONT - OAK
2 stops7h 00mSouthwest
Deal found 8/12$129
This KAYAK deal was found by Cheapflights users on 8/14. 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 KAYAK is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
mié. 10/19:40 amOAK - ONT
2 stops11h 20mSouthwest
vie. 10/35:55 pmONT - OAK
1 stop5h 50mSouthwest
Deal found 8/14$139
This Southwest deal was found by Cheapflights users on 8/14. 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.
vie. 10/108:40 pmOAK - ONT
Nonstop1h 20mSouthwest
dom. 10/127:30 amONT - OAK
Nonstop1h 20mSouthwest
Deal found 8/14$151
This Kiwi.com deal was found by Cheapflights users on 8/14. 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.
jue. 9/116:30 amOAK - ONT
1 stop5h 08mMultiple Airlines
jue. 9/186:00 amONT - OAK
1 stop7h 34mMultiple Airlines
Deal found 8/14$152
This Kiwi.com deal was found by Cheapflights users on 8/13. 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.
mié. 9/1010:56 amOAK - ONT
2 stops11h 00mMultiple Airlines
mié. 9/178:00 amONT - OAK
1 stop5h 34mMultiple Airlines
Deal found 8/13$167

Cheapflights Fare Finder

 
Customize your flight search to find flights from Oakland 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 agosto 14, 2025.
Use the filters below to find and compare flights from Oakland to Ontario that are best for you.

Fly from

Oakland

Fly to

Ontario

Route

Depart

Return

Price

OaklandOntario

OAK - ONT

OAKONT

Oakland

mié. 9/17

4:15 pm-5:35 pm

Nonstop1h 20m

Ontario

jue. 9/18

9:55 am-11:15 am

Nonstop1h 20m

$77

OaklandOntario

OAK - ONT

OAKONT

Oakland

mié. 9/10

9:55 am-11:15 am

Nonstop1h 20m

Ontario

mié. 9/17

8:15 am-9:35 am

Nonstop1h 20m

$77

OaklandOntario

OAK - ONT

OAKONT

Oakland

jue. 9/25

8:30 am-9:50 am

Nonstop1h 20m

Ontario

dom. 9/28

9:20 am-10:40 am

Nonstop1h 20m

$114

OaklandOntario

OAK - ONT

OAKONT

Oakland

vie. 10/24

8:40 pm-10:00 pm

Nonstop1h 20m

Ontario

lun. 10/27

8:35 pm-9:55 pm

Nonstop1h 20m

$114

OaklandOntario

OAK - ONT

OAKONT

Oakland

dom. 11/2

5:25 am-6:45 am

Nonstop1h 20m

Ontario

lun. 11/3

6:15 pm-7:40 pm

Nonstop1h 25m

$114

OaklandOntario

OAK - ONT

OAKONT

Oakland

mié. 10/1

4:15 pm-5:35 pm

Nonstop1h 20m

Ontario

vie. 10/3

6:30 pm-7:50 pm

Nonstop1h 20m

$114

OaklandOntario

OAK - ONT

OAKONT

Oakland

jue. 10/16

8:40 pm-10:00 pm

Nonstop1h 20m

Ontario

dom. 10/19

9:00 pm-10:20 pm

Nonstop1h 20m

$114

OaklandOntario

OAK - ONT

OAKONT

Oakland

vie. 9/26

8:30 am-9:50 am

Nonstop1h 20m

Ontario

lun. 9/29

5:50 am-7:10 am

Nonstop1h 20m

$114

OaklandOntario

OAK - ONT

OAKONT

Oakland

lun. 10/20

5:45 am-7:05 am

Nonstop1h 20m

$39

OaklandOntario

OAK - ONT

OAKONT

Oakland

sáb. 12/6

4:45 pm-6:05 pm

Nonstop1h 20m

$39

Flights are sorted by cheapest round-trip flights first.

Deals found on 8/13

Showing 1-10 of 16 results
1
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The best insider tips for Oakland to Ontario flights

Snippets provided in this section are AI-generated based on a summarization of Cheapflights-commissioned articles. The articles are presented as-is, for general informational purposes only, and may not be up-to-date. The opinions contained in the articles are original to the author and reflect their authentic experience, which may vary significantly from the experience of others.
Cheapflights partnered with top experts to bring you the best recommendations for your Oakland to Ontario trip
Airports
OAK

For quick access to your gate, OAK's smaller size makes navigation easy, especially compared to SFO.

Read more about OAKby Bill Fink
ONT

Consider renting a car at ONT for easy access to Southern California destinations like Palm Springs and Big Bear.

Read more about ONTby Bill Fink
Our travel experts
Bill Fink

Bill Fink

Expert on ONT and OAK

Bill Fink

Bill Fink

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

Best time to book a flight from Oakland to Ontario

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

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

Use this chart to determine the optimal time to book a round-trip flight from Oakland to Ontario. Price data was last updated on August 8, 2025.

To ensure you get the cheapest price possible for a flight from Oakland, California to Ontario, you should look to book at least 62 days in advance of your intended travel date. The price of your flight may increase if you delay and leave booking until a week or so before departure.

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

Currently, August is the cheapest month in which you can book a flight from Oakland, California to Ontario (average of $246). Flying from Oakland, California to Ontario in March is currently the most expensive (average of $328). 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 OAK to ONT?

Find hourly flight availability from Oakland 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 agosto 14, 2025.

A simple way to save on the total cost of your ticket is to fly from Oakland, California to Ontario in the evening. If you’re flexible enough to do this you can expect to save up to 11% on your trip compared to booking a flight in the morning.

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

Use this chart to determine the cheapest time to fly round-trip from Oakland to Ontario. Price data was last updated on August 10, 2025.

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

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 agosto 14, 2025.
Get a feel of what it's like to fly with Southwest, Delta, and United Airlines from Oakland 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
8.0
Very good
4,244 reviews

Boarding

8.1

Entertainment

7.5

Overall

8.0

Comfort

8.0

Food

7.0

Crew

8.6

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
4,244 reviews
Southwest
8.0
Very good
4,244 reviews

Boarding

8.1

Entertainment

7.5

Overall

8.0

Comfort

8.0

Food

7.0

Crew

8.6

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.
Delta
8.0
Very good
7,980 reviews
Southwest
8.0
Very good
4,244 reviews

Boarding

8.1

Entertainment

7.5

Overall

8.0

Comfort

8.0

Food

7.0

Crew

8.6

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.
United Airlines
7.4
Good
8,916 reviews
Southwest
8.0
Very good
4,244 reviews

Boarding

8.1

Entertainment

7.5

Overall

8.0

Comfort

8.0

Food

7.0

Crew

8.6

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.
Spirit Airlines
6.3
Okay
8,046 reviews
Southwest
8.0
Very good
4,244 reviews

Boarding

8.1

Entertainment

7.5

Overall

8.0

Comfort

8.0

Food

7.0

Crew

8.6

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
5.8
Fair
3,217 reviews
Southwest
8.0
Very good
4,244 reviews

Boarding

8.1

Entertainment

7.5

Overall

8.0

Comfort

8.0

Food

7.0

Crew

8.6

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 Oakland 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 Oakland to Ontario?

    If you book a flight from Oakland to Ontario, you will be flying from Oakland to Ontario. Flights to Ontario (ONT) from Oakland (OAK) take 1h 20m for a nonstop flight. There are 3 flights from Oakland to Ontario per day from 5 airlines.

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

    Within the past month, 6 users have taken a look at flights from Oakland to Ontario.

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

    Our cheapest airline available from Oakland, California to Ontario is Frontier. Our recent data shows that you can find tickets from as low as $27 on this airline. Additional options worth looking into are Spirit Airlines and United Airlines, starting at $46 and $58 round-trip. Users have found that Frontier is 88% cheaper than the other options available to this destination.

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

    Looking for the cheapest flight from Oakland, California to Ontario? While on average our users pay $193, our data indicates the cheapest price to be $38. The most popular route (Oakland - Ontario), is priced around $77.

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

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

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

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

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

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

    Currently, August is the cheapest month in which you can book a flight from Oakland, California to Ontario (average of $246). Flying from Oakland, California to Ontario in March is currently the most expensive (average of $328). 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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Alternative routes for Oakland to Ontario

See prices for flight routes from nearby airports that may be better suited for you.
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Top 5 airlines flying from Oakland to Ontario

Discover the top 5 airlines that operate flights from Oakland 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 agosto 14, 2025.
AirlineCheapestAverageFlexibilityOn-time
FrontierCheapest$27Average$96FlexibilityNo cancel feeOn-time62%
Spirit AirlinesCheapest$46Average$96FlexibilityNo cancel feeOn-time65%
United AirlinesCheapest$58Average$137FlexibilityNo cancel feeOn-time69%
DeltaCheapest$98Average$198FlexibilityNo cancel feeOn-timeN/A
SouthwestCheapest$168Average$272FlexibilityNo cancel feeOn-time63%

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