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Ontario

$81+ 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 9/8. Fares are subject to change and may not be available on all flights or dates of travel.
OAK — ONT
Aug 10 — Aug 171
Mon 8/10
Mon 8/17
1 adult, Economy
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Find cheap flights from Oakland to Ontario with Cheapflights

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Cheapflights Tip: The best prices from Oakland to Ontario are usually found in October or August, booked 49 days in advance, depart on a Tuesday or Thursday and return on a Saturday

Cheap 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 July 11, 2026.

This Southwest deal was found by Cheapflights users on 7/7. 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 8/412:15 pm
OAK
-
ONT
Nonstop1h 20m
Southwest
Tue 8/112:40 pm
ONT
-
OAK
Nonstop1h 15m
Southwest
Deal found 7/7$180
This Southwest deal was found by Cheapflights users on 7/8. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 8/63:45 pm
OAK
-
ONT
Nonstop1h 20m
Southwest
Mon 8/1010:30 am
ONT
-
OAK
Nonstop1h 20m
Southwest
Deal found 7/8$198
This Southwest deal was found by Cheapflights users on 7/7. 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.
Sat 8/85:15 am
OAK
-
ONT
1 stop6h 00m
Southwest
Wed 8/127:45 am
ONT
-
OAK
2 stops6h 35m
Southwest
Deal found 7/7$205
This Southwest deal was found by Cheapflights users on 7/10. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 9/93:25 pm
OAK
-
ONT
2 stops5h 30m
Southwest
Sat 9/1210:15 am
ONT
-
OAK
2 stops5h 55m
Southwest
Deal found 7/10$210
This Southwest deal was found by Cheapflights users on 7/9. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 9/195:10 am
OAK
-
ONT
2 stops6h 05m
Southwest
Mon 9/2110:30 am
ONT
-
OAK
Nonstop1h 20m
Southwest
Deal found 7/9$213
This Southwest deal was found by Cheapflights users on 7/11. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 8/103:45 pm
OAK
-
ONT
Nonstop1h 20m
Southwest
Mon 8/176:30 am
ONT
-
OAK
Nonstop1h 25m
Southwest
Deal found 7/11$219
This CheapOair deal was found by Cheapflights users on 7/7. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 9/2912:13 pm
OAK
-
ONT
1 stop3h 57m
Frontier
Wed 9/309:49 pm
ONT
-
OAK
1 stop21h 55m
Frontier
Deal found 7/7$220

Find 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 July 11, 2026.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$180
(Southwest)

One-way from

$81
(Southwest)

Popular in

February

Cheapest in

October

Average price

$309

Good round-trip deal

$309 or less

Good one-way deal

$210 or less
Provider with most accurate pricing for Oakland-Ontario flight deals.
Search Deals
Provider most trusted by Cheapflights users for Oakland-Ontario flights.
Search Deals
From Oakland to Ontario
Search Deals
One-way flight from Oakland to Ontario
Search Deals
Highest demand for flights based on searches. 17% potential increase in price ($63 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 3% potential price decrease ($10 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in July 2026
Search Deals
Price to beat on a round-trip flight from Oakland to Ontario.
Search Deals
Price to beat on a one-way flight from Oakland to Ontario.
Search Deals

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 July 11, 2026.
Use the filters below to find and compare flights from Oakland to Ontario that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

Cheapest round-trip

OaklandOntario

OAK - ONT

OAKONT

Oakland

Wed 9/9

2:40 pm-4:00 pm

Nonstop1h 20m

Ontario

Sat 9/12

4:00 pm-5:20 pm

Nonstop1h 20m

$180

OaklandOntario

OAK - ONT

OAKONT

Oakland

Thu 8/6

3:45 pm-5:05 pm

Nonstop1h 20m

Ontario

Mon 8/10

10:30 am-11:50 am

Nonstop1h 20m

$198

OaklandOntario

OAK - ONT

OAKONT

Oakland

Sat 9/19

8:30 am-3:15 pm

1 stop6h 45m

Ontario

Mon 9/21

10:30 am-11:50 am

Nonstop1h 20m

$208
Quickest round-trip

OaklandOntario

OAK - ONT

OAKONT

Oakland

Tue 8/18

2:40 pm-4:00 pm

Nonstop1h 20m

Ontario

Tue 8/25

2:40 pm-3:55 pm

Nonstop1h 15m

$249

OaklandOntario

OAK - ONT

OAKONT

Oakland

Thu 7/30

3:15 pm-4:35 pm

Nonstop1h 20m

Ontario

Thu 8/6

10:30 am-11:50 am

Nonstop1h 20m

$254

OaklandOntario

OAK - ONT

OAKONT

Oakland

Fri 8/7

5:20 am-9:20 am

1 stop4h 00m

Ontario

Sun 8/9

12:15 pm-1:30 pm

Nonstop1h 15m

$291

OaklandOntario

OAK - ONT

OAKONT

Oakland

Sat 8/1

7:05 pm-8:25 pm

Nonstop1h 20m

Ontario

Sun 8/2

8:30 pm-9:50 pm

Nonstop1h 20m

$309

OaklandOntario

OAK - ONT

OAKONT

Oakland

Thu 8/20

7:55 pm-9:15 pm

Nonstop1h 20m

Ontario

Thu 8/27

6:30 am-7:55 am

Nonstop1h 25m

$309

OaklandOntario

OAK - ONT

OAKONT

Oakland

Thu 7/30

3:15 pm-4:35 pm

Nonstop1h 20m

Ontario

Fri 7/31

5:15 pm-11:20 pm

1 stop6h 05m

$319
Cheapest one-way
Quickest one-way

OaklandOntario

OAK - ONT

OAKONT

Oakland

Wed 7/29

11:05 am-12:25 pm

Nonstop1h 20m

$155

Flights are sorted by cheapest round-trip flights first.

Deals found on 7/8

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

Compare providers for flights from Oakland 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 Oakland to Ontario in July.
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 Oakland, California-Ontario flights, users find the pricing of FlightHub to be most consistent on Cheapflights vs. FlightHub Users can find the same prices on Oakland, California-Ontario flight deals on Cheapflights vs. FlightHub >95% of the time. Price accuracy is based on data collected from Oakland, California-Ontario flight searches over the past month and is updated monthly.
  • Most trusted provider: When it comes to deals on Oakland, California-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 Oakland, California-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 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?

To ensure you get the cheapest price possible for a flight from Oakland, California to Ontario, you should look to book at least 48 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, October is the cheapest month in which you can book a flight from Oakland, California to Ontario (average of $228). Flying from Oakland, California to Ontario in February is currently the most expensive (average of $411). 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 July 11, 2026.

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 14% on your trip compared to booking a flight at noon.

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 July 4, 2026.

Travelers seeking maximum savings on their Oakland, California to Ontario flight should consider departing on Tuesday afternoons when fares are most often at their lowest. Wednesday 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 Oakland, California to Ontario?

The best insider tips for Oakland to Ontario 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 Oakland to Ontario 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 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 July 11, 2026.
Get a feel of what it's like to fly with Southwest and Frontier 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
7.9
Good
4,248 reviews

Crew

8.6

Boarding

8.1

Overall

7.9

Entertainment

7.5

Comfort

8.0

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
7.9
Good
4,248 reviews
Southwest
7.9
Good
4,248 reviews

Crew

8.6

Boarding

8.1

Overall

7.9

Entertainment

7.5

Comfort

8.0

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
2,834 reviews
Southwest
7.9
Good
4,248 reviews

Crew

8.6

Boarding

8.1

Overall

7.9

Entertainment

7.5

Comfort

8.0

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 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 2 flights from Oakland to Ontario per day from 2 airlines.

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

    Within the past month, 18 users have taken a look at flights from Oakland to Ontario.

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

    There are many flights that can get you from Oakland, California to Ontario in 1h 20m. Fly via Southwest to get the fastest option. There are 361 mi between Oakland, California and Ontario. All flights are typically nonstop.

  • 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 $39 on this airline. An additional option worth looking into is Southwest, starting at $122. Users have found that Frontier is 87% cheaper than the other options available to this destination.

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

    The cheapest airlines for a one-way flight from Oakland, California to Ontario are Frontier ($33), Southwest ($48), and Alaska Airlines ($100).

  • 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 $338, our data indicates the cheapest price to be $108. The most popular route (Oakland - Ontario), is priced around $180.

  • 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, October is the cheapest month in which you can book a flight from Oakland, California to Ontario (average of $228). Flying from Oakland, California to Ontario in February is currently the most expensive (average of $411). 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

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Top 2 airlines flying from Oakland to Ontario

Discover the top 2 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 July 11, 2026.
AirlineCheapestAverageFlexibilityOn-time
FrontierCheapest$39Average$128FlexibilityNo cancel feeOn-time62%
SouthwestCheapest$122Average$297FlexibilityNo cancel feeOn-time63%

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