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$64+ 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 9/20. Fares are subject to change and may not be available on all flights or dates of travel.
SAN — ONT
Aug 3 — Aug 101
Sun 8/3
Sun 8/10
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 July 29, 2025.

Round-trip from

$294
(American Airlines)

One-way from

$64
(Trip.com)

Popular in

March

Cheapest in

July

Average price

$179
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. 12% potential increase in price ($30 potential increase over avg. RT price).
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Cheapest flight prices on average. 2% potential price decrease ($6 potential savings vs. average RT price).
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Average for round-trip flights in July 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 July 29, 2025.

This American Airlines deal was found by Cheapflights users on 7/28. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 8/2512:50 pmSAN - ONT
1 stop27h 34mAmerican Airlines
Mon 9/17:02 pmONT - SAN
1 stop20h 23mAmerican Airlines
Deal found 7/28$294
This United Airlines deal was found by Cheapflights users on 7/28. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 9/207:00 amSAN - ONT
1 stop13h 43mUnited Airlines
Sat 9/271:53 pmONT - SAN
1 stop8h 34mUnited Airlines
Deal found 7/28$363
This Alaska Airlines deal was found by Cheapflights users on 7/27. 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.
Sun 12/1410:45 amSAN - ONT
1 stop9h 02mAlaska Airlines
Sat 12/2012:48 pmONT - SAN
1 stop11h 19mAlaska Airlines
Deal found 7/27$482

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 July 29, 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

Mon 8/25

12:50 pm-4:24 pm

1 stop27h 34m

Ontario

Mon 9/1

7:02 pm-3:25 pm

1 stop20h 23m

$294

San DiegoOntario

SAN - ONT

SANONT

San Diego

Sat 9/20

7:00 am-8:43 pm

1 stop13h 43m

Ontario

Sat 9/27

1:53 pm-10:27 pm

1 stop8h 34m

$363

San DiegoOntario

SAN - ONT

SANONT

San Diego

Tue 8/12

5:51 pm-12:15 am

1 stop6h 24m

Ontario

Fri 8/15

6:58 pm-9:50 am

1 stop14h 52m

$657

San DiegoOntario

SAN - ONT

SANONT

San Diego

Sat 9/20

6:15 am-9:56 pm

1 stop15h 41m

$64

San DiegoOntario

SAN - ONT

SANONT

San Diego

Sat 8/30

6:15 am-5:37 pm

1 stop11h 22m

$157

San DiegoOntario

SAN - ONT

SANONT

San Diego

Tue 9/9

10:59 am-5:00 pm

1 stop6h 01m

$171

San DiegoOntario

SAN - ONT

SANONT

San Diego

Wed 8/13

4:20 pm-6:17 pm

1 stop25h 57m

$281

Flights are sorted by cheapest round-trip flights first.

Deals found on 7/27

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 July 29, 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.

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 29, 2025.
See what other customers who have flown with Alaska Airlines, United Airlines, and American Airlines from San Diego to Ontario have to say. You can also see how each airline compares in terms of entertainment options, comfort, food, crew/service, and boarding process.
Alaska Airlines
8.0
Very good
10,000 reviews

Overall

8.0

Boarding

8.1

Comfort

7.8

Food

7.1

Crew

8.5

Entertainment

7.1

Reviews

1 / 20
10.0
Excellent

James,Apr 2025

LAX - SFO

Good flight except the uncontrollable cold air from the ceiling.
Alaska Airlines
8.0
Very good
10,000 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Overall

8.0

Boarding

8.1

Comfort

7.8

Food

7.1

Crew

8.5

Entertainment

7.1

Reviews

1 / 20
10.0
Excellent

James,Apr 2025

LAX - SFO

Good flight except the uncontrollable cold air from the ceiling.
United Airlines
7.4
Good
8,899 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Overall

8.0

Boarding

8.1

Comfort

7.8

Food

7.1

Crew

8.5

Entertainment

7.1

Reviews

1 / 20
10.0
Excellent

James,Apr 2025

LAX - SFO

Good flight except the uncontrollable cold air from the ceiling.
American Airlines
7.2
Good
10,000 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Overall

8.0

Boarding

8.1

Comfort

7.8

Food

7.1

Crew

8.5

Entertainment

7.1

Reviews

1 / 20
10.0
Excellent

James,Apr 2025

LAX - SFO

Good flight except the uncontrollable cold air from the ceiling.

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.

  • What are the cheapest airlines to fly from San Diego to Ontario one-way?

    One-way options have recently been found by users for as low as $157 on United Airlines. Other airlines that offer cheap prices include Alaska Airlines from $171 and American Airlines from $281 one-way.

  • 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.

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