HomeSearch by dateVacation packagesHotelsFlight dealsCar rentalTravel tips & news
Ontario

$79+ 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 9/16. Fares are subject to change and may not be available on all flights or dates of travel.
OAK — ONT
Sep 15 — Sep 221
Tue 9/15
Tue 9/22
1 adult, Economy
We work with more than 300 partners to bring you better travel deals

Find cheap flights from Oakland to Ontario with Cheapflights

1. Tell us where you want to go

Enter your travel information like dates, passengers, trip type (one-way or round trip), and preferred cabin class then click “Find deals”

2. Select your favorite providers

We find the providers serving your travel needs. Choose up to four travel providers to compare side-by-side for flights, hotels, or car rentals.

3. Compare prices and book

Review each provider’s pricing and select the best option for you! Book through your favorite provider’s website for a seamless experience.
Cheapflights Tip: The best prices from Oakland to Ontario are usually found in October or November, booked 29 days in advance, depart on a Tuesday or Thursday and return on a Thursday

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 August 16, 2026.

This Frontier deal was found by Cheapflights users on 8/15. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 9/1612:47 pm -
1 stop4h 12m
Mon 9/212:30 pm -
1 stop3h 26m
Deal found 8/15$158
This Frontier deal was found by Cheapflights users on 8/16. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 9/1010:17 am -
1 stop6h 42m
Mon 9/148:24 pm -
1 stop15h 27m
Deal found 8/16$159
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.
Tue 9/1512:47 pm -
1 stop20h 22m
Tue 9/225:44 pm -
1 stop18h 07m
Deal found 8/13$163
This CheapOair 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 10/110:17 am -
1 stop20h 47m
Mon 10/52:30 pm -
1 stop21h 21m
Deal found 8/14$168
This Kiwi.com 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 9/1512:47 pm -
1 stop20h 22m
Thu 9/178:00 am -
1 stop9h 56m
Deal found 8/12$177
This CheapOair 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 9/812:13 pm -
1 stop20h 56m
Fri 9/118:00 am -
1 stop9h 56m
Deal found 8/14$178
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.
Mon 11/1612:13 pm -
1 stop8h 35m
Wed 11/1812:57 pm -
1 stop22h 21m
Deal found 8/13$181
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.
Tue 11/173:05 pm -
2 stops5h 55m
Wed 11/186:55 pm -
Nonstop1h 25m
Deal found 8/13$183
This Frontier 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 9/1710:17 am -
1 stop6h 42m
Mon 9/212:30 pm -
1 stop3h 26m
Deal found 8/14$184
This Southwest deal was found by Cheapflights users on 8/11. 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.
Tue 9/88:30 pm -
Nonstop1h 30m
Tue 9/156:10 pm -
Nonstop1h 20m
Deal found 8/11$186

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 August 16, 2026.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$158
(Frontier)

One-way from

$79
(Frontier)

Popular in

February

Cheapest in

October

Average price

$299

Good round-trip deal

$309 or less

Good one-way deal

$117 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. 15% potential increase in price ($57 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 August 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 August 16, 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 Oakland - ONT Ontario

OAKONT

Oakland

Wed 9/16

2:40 pm-4:00 pm

Nonstop1h 20m

Ontario

Wed 9/16

6:10 pm-7:30 pm

Nonstop1h 20m

$168

OaklandOntario

OAK Oakland - ONT Ontario

OAKONT

Oakland

Thu 9/17

5:05 am-9:55 am

1 stop4h 50m

Ontario

Mon 9/21

6:30 am-7:55 am

Nonstop1h 25m

$214

OaklandOntario

OAK Oakland - ONT Ontario

OAKONT

Oakland

Fri 9/11

6:00 am-7:25 am

Nonstop1h 25m

Ontario

Fri 9/18

10:30 am-11:50 am

Nonstop1h 20m

$222

OaklandOntario

OAK Oakland - ONT Ontario

OAKONT

Oakland

Fri 10/9

6:20 am-7:40 am

Nonstop1h 20m

Ontario

Mon 10/12

6:55 pm-12:35 am

1 stop5h 40m

$243

OaklandOntario

OAK Oakland - ONT Ontario

OAKONT

Oakland

Sat 9/5

10:15 am-3:15 pm

1 stop5h 00m

Ontario

Mon 9/7

6:30 am-7:55 am

Nonstop1h 25m

$273

OaklandOntario

OAK Oakland - ONT Ontario

OAKONT

Oakland

Thu 9/10

7:55 pm-9:20 pm

Nonstop1h 25m

Ontario

Sun 9/13

6:00 am-7:15 am

Nonstop1h 15m

$278

OaklandOntario

OAK Oakland - ONT Ontario

OAKONT

Oakland

Sat 11/7

5:10 am-11:20 am

2 stops6h 10m

Ontario

Sun 11/8

1:20 pm-7:15 pm

1 stop5h 55m

$287

OaklandOntario

OAK Oakland - ONT Ontario

OAKONT

Oakland

Sat 9/5

6:25 pm-7:50 pm

Nonstop1h 25m

Ontario

Sun 9/6

7:05 am-11:15 am

1 stop4h 10m

$288
Quickest round-trip

OaklandOntario

OAK Oakland - ONT Ontario

OAKONT

Oakland

Fri 10/2

10:40 am-12:00 pm

Nonstop1h 20m

Ontario

Sun 10/4

7:10 am-8:25 am

Nonstop1h 15m

$288

OaklandOntario

OAK Oakland - ONT Ontario

OAKONT

Oakland

Fri 11/20

2:05 pm-3:25 pm

Nonstop1h 20m

Ontario

Sun 11/22

5:45 am-7:10 am

Nonstop1h 25m

$319

Flights are sorted by cheapest round-trip flights first.

Deals found on 8/11

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

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 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 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 28 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 $239). 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 August 16, 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 12% 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 August 8, 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?

Airfare is below average for this route at the moment.

Oakland, California to Ontario flights typically cost between $269 and $563 in September.
The cheapest round-trip price found within the last 5 days was $158 on Frontier (Sep 16-Sep 21).

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 August 16, 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
8.0
Very good
4,218 reviews

Entertainment

7.5

Food

7.0

Crew

8.6

Comfort

8.0

Overall

8.0

Boarding

8.1

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
4,218 reviews
Southwest
8.0
Very good
4,218 reviews

Entertainment

7.5

Food

7.0

Crew

8.6

Comfort

8.0

Overall

8.0

Boarding

8.1

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
2,684 reviews
Southwest
8.0
Very good
4,218 reviews

Entertainment

7.5

Food

7.0

Crew

8.6

Comfort

8.0

Overall

8.0

Boarding

8.1

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 is 1 flight 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 $146. 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 ($89), and Alaska Airlines ($106).

  • 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 $300, our data indicates the cheapest price to be $109. The most popular route (Oakland - Ontario), is priced around $158.

  • 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 $239). 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

Browse thousands of different options on Cheapflights for your next trip

Toggle through the tabs below to find thousands of options on Cheapflights for your next trip.

Alternative routes for Oakland to Ontario

See prices for flight routes from nearby airports that may be better suited for you.
Los Angeles to Las Vegas flights
San Francisco to Las Vegas flights
San Francisco to Ontario flights
Los Angeles to San Francisco flights
San Francisco to Los Angeles flights
Ontario to San Francisco flights
San Francisco to Santa Ana flights
Ontario to Las Vegas flights
Santa Ana to San Francisco flights
San Diego to Las Vegas flights
San Jose to Las Vegas flights
Burbank to Las Vegas flights
Los Angeles to San Jose flights
Oakland to Las Vegas flights
Santa Ana to Las Vegas flights
San Jose to Los Angeles flights
San Diego to San Francisco flights
Sacramento to Las Vegas flights
San Francisco to Burbank flights
San Francisco to San Diego flights
Las Vegas to Los Angeles flights
San Jose to San Diego flights
Burbank to San Francisco flights
Oakland to San Diego flights
Sacramento to Los Angeles flights
Los Angeles to Sacramento flights
Los Angeles to Reno flights
Oakland to Santa Ana flights
San Francisco to Palm Springs flights
Las Vegas to Reno flights
San Jose to Ontario flights
San Jose to Santa Ana flights
Las Vegas to San Francisco flights
Fresno to Las Vegas flights
Reno to Las Vegas flights
Sacramento to San Diego flights
Stockton to Las Vegas flights
Long Beach to San Francisco flights
Ontario to San Jose flights
Santa Ana to Oakland flights
Los Angeles to Oakland flights
Las Vegas to Ontario flights
San Francisco to Long Beach flights
San Diego to Oakland flights
Las Vegas to San Diego flights
Long Beach to Las Vegas flights
Sacramento to Ontario flights
Santa Ana to San Jose flights
Ontario to Sacramento flights
Santa Rosa to Las Vegas flights

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 August 16, 2026.
AirlineCheapestAverageFlexibilityOn-time
FrontierCheapest$39Average$160FlexibilityNo cancel feeOn-time62%
SouthwestCheapest$146Average$302FlexibilityNo cancel feeOn-time63%

100% Free

Cheapflights is completely free to use, so you can start saving the moment you arrive.

Book with Flexibility

Our users can plan ahead with confidence and find flights with no change fees

Travel Smart

Millions of people come to us for their flight needs every year. We help make travel planning easy by providing useful insights and data-driven graphs that can inform your decisions.