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Ontario

$132+ Cheap flights from San Diego to Ontario (SAN - 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 4/7. Fares are subject to change and may not be available on all flights or dates of travel.
SAN — ONT
Apr 15 — Apr 221
Wed 4/15
Wed 4/22
1 adult, Economy
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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 March 16, 2026.

This Kiwi.com deal was found by Cheapflights users on 3/12. 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.
Thu 4/99:02 pm
SAN
-
ONT
1 stop11h 02m
Frontier
Wed 4/1512:59 am
ONT
-
SAN
1 stop7h 35m
Frontier
Deal found 3/12$189
This Alaska Airlines 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 Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 4/149:14 pm
SAN
-
ONT
1 stop18h 28m
Alaska Airlines
Wed 4/2912:48 pm
ONT
-
SAN
1 stop20h 22m
Alaska Airlines
Deal found 3/15$253
This Alaska Airlines deal was found by Cheapflights users on 3/12. 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 Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 4/287:35 pm
SAN
-
ONT
1 stop14h 10m
Alaska Airlines
Thu 5/73:26 pm
ONT
-
SAN
1 stop8h 33m
Alaska Airlines
Deal found 3/12$265
This Alaska Airlines deal was found by Cheapflights users on 3/12. 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 Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 5/55:17 pm
SAN
-
ONT
1 stop18h 51m
Alaska Airlines
Wed 5/63:24 pm
ONT
-
SAN
1 stop7h 12m
Alaska Airlines
Deal found 3/12$280
This American Airlines deal was found by Cheapflights users on 3/12. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 4/99:28 am
SAN
-
ONT
1 stop9h 02m
American Airlines
Thu 4/167:35 pm
ONT
-
SAN
1 stop13h 03m
American Airlines
Deal found 3/12$283
This United Airlines deal was found by Cheapflights users on 3/11. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 5/57:15 am
SAN
-
ONT
1 stop10h 37m
United Airlines
Wed 5/66:00 am
ONT
-
SAN
1 stop12h 33m
United Airlines
Deal found 3/11$287
This Alaska Airlines deal was found by Cheapflights users on 3/11. 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 Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/159:14 pm
SAN
-
ONT
1 stop18h 28m
Alaska Airlines
Fri 4/174:22 pm
ONT
-
SAN
1 stop16h 36m
Alaska Airlines
Deal found 3/11$323
This Kiwi.com deal was found by Cheapflights users on 3/12. 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.
Fri 3/279:58 pm
SAN
-
ONT
1 stop15h 30m
Frontier
Tue 3/312:23 pm
ONT
-
SAN
2 stops33h 39m
Frontier
Deal found 3/12$328
This Alaska Airlines deal was found by Cheapflights users on 3/14. 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 Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/295:17 pm
SAN
-
ONT
1 stop18h 51m
Alaska Airlines
Tue 5/512:48 pm
ONT
-
SAN
1 stop20h 22m
Alaska Airlines
Deal found 3/14$343
This Alaska Airlines deal was found by Cheapflights users on 3/11. 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 Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 4/247:35 pm
SAN
-
ONT
1 stop14h 10m
Alaska Airlines
Sun 4/266:00 am
ONT
-
SAN
1 stop9h 53m
Alaska Airlines
Deal found 3/11$354

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 March 16, 2026.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$177
(Kiwi.com)

One-way from

$132
(Alaska Airlines)

Popular in

March

Cheapest in

February

Average price

$299
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
One-way flight from San Diego to Ontario
Search Deals
Highest demand for flights based on searches. 9% potential increase in price ($22 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 3% potential price decrease ($9 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in March 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 March 16, 2026.
Use the filters below to find and compare flights from San Diego to Ontario that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

Cheapest round-trip

San DiegoOntario

SAN - ONT

SANONT

San Diego

Tue 4/14

9:14 pm-3:42 pm

1 stop18h 28m

Ontario

Wed 4/29

12:48 pm-9:10 am

1 stop20h 22m

$253

San DiegoOntario

SAN - ONT

SANONT

San Diego

Tue 4/28

7:35 pm-9:45 am

1 stop14h 10m

Ontario

Thu 5/7

3:26 pm-11:59 pm

1 stop8h 33m

$265

San DiegoOntario

SAN - ONT

SANONT

San Diego

Tue 5/5

5:17 pm-12:08 pm

1 stop18h 51m

Ontario

Wed 5/6

3:24 pm-10:36 pm

1 stop7h 12m

$280
Quickest round-trip

San DiegoOntario

SAN - ONT

SANONT

San Diego

Thu 4/9

9:28 am-6:30 pm

1 stop9h 02m

Ontario

Thu 4/16

7:35 pm-8:38 am

1 stop13h 03m

$283

San DiegoOntario

SAN - ONT

SANONT

San Diego

Tue 5/5

7:15 am-5:52 pm

1 stop10h 37m

Ontario

Wed 5/6

6:00 am-6:33 pm

1 stop12h 33m

$287

San DiegoOntario

SAN - ONT

SANONT

San Diego

Wed 4/15

9:14 pm-3:42 pm

1 stop18h 28m

Ontario

Fri 4/17

4:22 pm-8:58 am

1 stop16h 36m

$323

San DiegoOntario

SAN - ONT

SANONT

San Diego

Fri 3/27

9:58 pm-1:28 pm

1 stop15h 30m

Ontario

Tue 3/31

2:23 pm-12:02 am

2 stops33h 39m

$328

San DiegoOntario

SAN - ONT

SANONT

San Diego

Wed 4/29

5:17 pm-12:08 pm

1 stop18h 51m

Ontario

Tue 5/5

12:48 pm-9:10 am

1 stop20h 22m

$343

San DiegoOntario

SAN - ONT

SANONT

San Diego

Tue 5/5

5:17 pm-12:08 pm

1 stop18h 51m

Ontario

Mon 5/11

12:48 pm-9:45 pm

1 stop8h 57m

$343

San DiegoOntario

SAN - ONT

SANONT

San Diego

Fri 4/24

7:35 pm-9:45 am

1 stop14h 10m

Ontario

Sun 4/26

6:00 am-3:53 pm

1 stop9h 53m

$354

Flights are sorted by cheapest round-trip flights first.

Deals found on 3/13

Showing 1-10 of 20 resultsSorted by cheapest first
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 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 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 $101). Flying from San Diego to Ontario in January is currently the most expensive (average of $188). 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 9h 02m. There are 94 mi between San Diego and Ontario. When browsing for deals, the options you’ll see will be for both nonstop flights and flights with stops.

  • 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 $101). Flying from San Diego to Ontario in January is currently the most expensive (average of $188). 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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