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$87+ 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 10/11. Fares are subject to change and may not be available on all flights or dates of travel.
SAN — ONT
oct. 15 — oct. 221
mié. 10/15
mié. 10/22
1 adult, Economy
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Cheap 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 septiembre 15, 2025.

Round-trip from

$157
(Kiwi.com)

One-way from

$87
(Kiwi.com)

Popular in

August

Cheapest in

February

Average price

$184
From San Diego to Ontario
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One-way flight from San Diego to Ontario
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Highest demand for flights based on searches. 21% potential increase in price ($142 potential increase over avg. RT price).
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Cheapest flight prices on average. 3% potential price decrease ($16 potential savings vs. average RT price).
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Average for round-trip flights in September 2025
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Find 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 septiembre 15, 2025.

This Kiwi.com deal was found by Cheapflights users on 9/15. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
mar. 9/301:35 pmSAN - ONT
1 stop8h 21mMultiple Airlines
sáb. 10/41:37 pmONT - SAN
1 stop4h 53mMultiple Airlines
Deal found 9/15$157
This Kiwi.com deal was found by Cheapflights users on 9/15. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
mié. 10/158:00 amSAN - ONT
1 stop12h 42mFrontier
mié. 10/228:00 amONT - SAN
1 stop13h 20mFrontier
Deal found 9/15$171
This Kiwi.com deal was found by Cheapflights users on 9/15. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
mar. 9/308:00 amSAN - ONT
1 stop13h 56mFrontier
sáb. 10/48:00 amONT - SAN
2 stops15h 40mFrontier
Deal found 9/15$193
This Frontier deal was found by Cheapflights users on 9/15. 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.
vie. 10/241:06 pmSAN - ONT
1 stop10h 44mFrontier
sáb. 10/257:04 amONT - SAN
1 stop6h 24mFrontier
Deal found 9/15$242
This Frontier deal was found by Cheapflights users on 9/15. 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.
sáb. 10/252:24 pmSAN - ONT
1 stop9h 26mFrontier
dom. 10/268:34 amONT - SAN
1 stop9h 54mFrontier
Deal found 9/15$250
This Frontier deal was found by Cheapflights users on 9/15. 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.
dom. 9/219:03 pmSAN - ONT
1 stop10h 50mFrontier
lun. 9/294:08 pmONT - SAN
1 stop7h 45mFrontier
Deal found 9/15$257
This Frontier deal was found by Cheapflights users on 9/14. 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.
mié. 10/17:15 amSAN - ONT
1 stop12h 39mFrontier
vie. 10/34:08 pmONT - SAN
1 stop7h 45mFrontier
Deal found 9/14$264
This Frontier deal was found by Cheapflights users on 9/15. 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.
lun. 9/2210:20 amSAN - ONT
1 stop9h 34mFrontier
lun. 9/294:08 pmONT - SAN
1 stop7h 45mFrontier
Deal found 9/15$280
This Frontier deal was found by Cheapflights users on 9/15. 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.
lun. 9/2910:20 amSAN - ONT
1 stop9h 34mFrontier
jue. 10/98:34 amONT - SAN
1 stop9h 54mFrontier
Deal found 9/15$314
This Frontier deal was found by Cheapflights users on 9/14. 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.
dom. 9/149:03 pmSAN - ONT
1 stop10h 50mFrontier
jue. 9/188:59 pmONT - SAN
1 stop14h 10mFrontier
Deal found 9/14$336

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 septiembre 15, 2025.
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

mar. 9/30

1:35 pm-9:56 pm

1 stop8h 21m

Ontario

sáb. 10/4

1:37 pm-6:30 pm

1 stop4h 53m

$157

San DiegoOntario

SAN - ONT

SANONT

San Diego

mié. 10/15

8:00 am-8:42 pm

1 stop12h 42m

Ontario

mié. 10/22

8:00 am-9:20 pm

1 stop13h 20m

$171

San DiegoOntario

SAN - ONT

SANONT

San Diego

mar. 9/30

8:00 am-9:56 pm

1 stop13h 56m

Ontario

sáb. 10/4

8:00 am-11:40 pm

2 stops15h 40m

$193

San DiegoOntario

SAN - ONT

SANONT

San Diego

sáb. 10/25

2:24 pm-11:50 pm

1 stop9h 26m

Ontario

dom. 10/26

8:34 am-6:28 pm

1 stop9h 54m

$250

San DiegoOntario

SAN - ONT

SANONT

San Diego

sáb. 10/4

7:15 am-7:54 pm

1 stop12h 39m

Ontario

lun. 10/6

4:08 pm-11:53 pm

1 stop7h 45m

$264

San DiegoOntario

SAN - ONT

SANONT

San Diego

mié. 10/1

7:15 am-7:54 pm

1 stop12h 39m

Ontario

vie. 10/3

4:08 pm-11:53 pm

1 stop7h 45m

$264

San DiegoOntario

SAN - ONT

SANONT

San Diego

lun. 9/29

10:20 am-7:54 pm

1 stop9h 34m

Ontario

jue. 10/9

8:34 am-6:28 pm

1 stop9h 54m

$314

San DiegoOntario

SAN - ONT

SANONT

San Diego

jue. 10/9

6:41 am-11:50 pm

1 stop17h 09m

Ontario

dom. 10/12

8:34 am-6:28 pm

1 stop9h 54m

$314

San DiegoOntario

SAN - ONT

SANONT

San Diego

lun. 9/29

10:20 am-7:54 pm

1 stop9h 34m

Ontario

vie. 10/3

4:08 pm-11:53 pm

1 stop7h 45m

$344

San DiegoOntario

SAN - ONT

SANONT

San Diego

lun. 9/29

10:20 am-7:54 pm

1 stop9h 34m

Ontario

lun. 10/6

4:08 pm-11:53 pm

1 stop7h 45m

$346

Flights are sorted by cheapest round-trip flights first.

Deals found on 9/15

Showing 1-10 of 22 results
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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, August is the cheapest month in which you can book a flight from San Diego to Ontario (average of $246). Flying from San Diego 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 SAN to ONT?

Find hourly flight availability from San Diego 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 septiembre 15, 2025.

It’s optimal to fly from San Diego to Ontario in the morning. By choosing this option you can save up to 13% on the cost of your flight, compared to a flight at noon.

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 12h 42m. 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, August is the cheapest month in which you can book a flight from San Diego to Ontario (average of $246). Flying from San Diego 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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