HomeSearch by dateVacation packagesHotelsFlight dealsCar rentalTravel tips & news
Ontario

$104+ Cheap flights from San Diego to Ontario (SAN - ONT)

This is the cheapest round-trip flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 2/24. Fares are subject to change and may not be available on all flights or dates of travel.
SAN — ONT
Feb 28 — Mar 71
Sat 2/28
Sat 3/7
1 adult, Economy
We work with more than 300 partners to bring you better travel deals

Find cheap flights from San Diego 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.

Cheap flight deals from San Diego to Ontario

Cheapest flights from San Diego to Ontario
Explore the most affordable flight options available from San Diego to Ontario. Find the lowest fares from popular airlines and budget airlines, with prices last updated on January 29, 2026.

This Kiwi.com deal was found by Cheapflights users on 1/27. 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 2/247:11 am
SAN
-
ONT
1 stop14h 23m
Frontier
Tue 3/38:40 am
ONT
-
SAN
1 stop13h 01m
Frontier
Deal found 1/27$104
This Kiwi.com deal was found by Cheapflights users on 1/27. 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 2/92:52 pm
SAN
-
ONT
1 stop23h 00m
Frontier
Thu 2/127:22 pm
ONT
-
SAN
1 stop24h 01m
Frontier
Deal found 1/27$173
This Kiwi.com deal was found by Cheapflights users on 1/29. 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.
Sat 2/710:34 am
SAN
-
ONT
1 stop12h 50m
Frontier
Mon 2/98:05 pm
ONT
-
SAN
2 stops24h 19m
Frontier
Deal found 1/29$240
This Alaska Airlines deal was found by Cheapflights users on 1/27. 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 Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 4/147:59 am
SAN
-
ONT
1 stop7h 43m
Alaska Airlines
Tue 4/214:22 pm
ONT
-
SAN
1 stop19h 17m
Alaska Airlines
Deal found 1/27$283
This American Airlines deal was found by Cheapflights users on 1/26. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 2/249:44 am
SAN
-
ONT
1 stop25h 44m
American Airlines
Tue 3/39:53 am
ONT
-
SAN
1 stop10h 21m
American Airlines
Deal found 1/26$299
This Kiwi.com deal was found by Cheapflights users on 1/28. 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 2/139:45 am
SAN
-
ONT
1 stop21h 41m
Frontier
Tue 2/172:06 pm
ONT
-
SAN
2 stops27h 45m
Frontier
Deal found 1/28$303
This Expedia deal was found by Cheapflights users on 1/27. 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 Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 2/248:19 pm
SAN
-
ONT
2 stops18h 49m
Alaska Airlines
Tue 3/36:14 am
ONT
-
SAN
2 stops10h 53m
Alaska Airlines
Deal found 1/27$311

Find flight deals from San Diego to Ontario

Discover tips and strategies to find the most affordable flight options for your journey from San Diego (SAN) 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 January 29, 2026.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$104
(Kiwi.com)

Popular in

March

Cheapest in

July

Average price

$249
Provider with most accurate pricing for San Diego-Ontario flight deals.
Search Deals
Provider most trusted by Cheapflights users for San Diego-Ontario flights.
Search Deals
From San Diego to Ontario
Search Deals
Highest demand for flights based on searches. 12% potential increase in price ($28 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 2% potential price decrease ($6 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in January 2026
Search Deals

Cheapflights Fare Finder

 
Customize your flight search to find flights from San Diego 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 January 29, 2026.
Use the filters below to find and compare flights from San Diego to Ontario that are best for you.

Fly from

San Diego

Fly to

Ontario

Route

Depart

Return

Price

San DiegoOntario

SAN - ONT

SANONT

San Diego

Tue 2/24

7:11 am-9:34 pm

1 stop14h 23m

Ontario

Tue 3/3

8:40 am-9:41 pm

1 stop13h 01m

$104

San DiegoOntario

SAN - ONT

SANONT

San Diego

Mon 2/9

2:52 pm-1:52 pm

1 stop23h 00m

Ontario

Thu 2/12

7:22 pm-7:23 pm

1 stop24h 01m

$173

San DiegoOntario

SAN - ONT

SANONT

San Diego

Tue 4/14

7:59 am-3:42 pm

1 stop7h 43m

Ontario

Tue 4/21

4:22 pm-11:39 am

1 stop19h 17m

$283

San DiegoOntario

SAN - ONT

SANONT

San Diego

Tue 2/24

9:44 am-11:28 am

1 stop25h 44m

Ontario

Tue 3/3

9:53 am-8:14 pm

1 stop10h 21m

$299

San DiegoOntario

SAN - ONT

SANONT

San Diego

Fri 2/13

9:45 am-7:26 am

1 stop21h 41m

Ontario

Tue 2/17

2:06 pm-5:51 pm

2 stops27h 45m

$303

San DiegoOntario

SAN - ONT

SANONT

San Diego

Tue 2/24

8:19 pm-3:08 pm

2 stops18h 49m

Ontario

Tue 3/3

6:14 am-5:07 pm

2 stops10h 53m

$311

San DiegoOntario

SAN - ONT

SANONT

San Diego

Tue 3/24

9:14 pm-3:42 pm

1 stop18h 28m

$147

San DiegoOntario

SAN - ONT

SANONT

San Diego

Tue 4/14

7:59 am-3:42 pm

1 stop7h 43m

$147

San DiegoOntario

SAN - ONT

SANONT

San Diego

Tue 4/21

5:06 pm-12:08 pm

1 stop19h 02m

$147

San DiegoOntario

SAN - ONT

SANONT

San Diego

Wed 4/15

9:14 pm-3:42 pm

1 stop18h 28m

$147

Flights are sorted by cheapest round-trip flights first.

Deals found on 1/27

Showing 1-10 of 17 results
1
2

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

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

What is the cheapest month to book a flight from San Diego to Ontario?

Currently, July is the cheapest month in which you can book a flight from San Diego to Ontario (average of $104). Flying from San Diego to Ontario in June is currently the most expensive (average of $179). 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.

Related info for your journey

Find useful and relevant information for your journey from San Diego to Ontario. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.

  • How long is the flight from San Diego to Ontario?

    Departing from San Diego to Ontario will take you 14h 23m. There are 94 mi between San Diego and Ontario.

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

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

  • How can I find direct flights from San Diego to Ontario?

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

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

    Yes. Cheapflights offers flight deals from San Diego 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 San Diego to Ontario?

    Currently, July is the cheapest month in which you can book a flight from San Diego to Ontario (average of $104). Flying from San Diego to Ontario in June is currently the most expensive (average of $179). 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 San Diego to Ontario

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

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.