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$172+ 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 8/20. Fares are subject to change and may not be available on all flights or dates of travel.
SAN — ONT
May 17 — May 241
Sat 5/17
Sat 5/24
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 May 12, 2025.

Most accurate provider

FlightHub
3 stars

Most trusted provider

Expedia
3 stars

Round-trip from

$367
(American Airlines)

One-way from

$172
(Alaska Airlines)

Popular in

April

Cheapest in

February

Average price

$412
Provider with most accurate pricing for San Diego-Ontario flight deals.
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Provider most trusted by Cheapflights users for San Diego-Ontario flights.
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From San Diego to Ontario
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One-way flight from San Diego to Ontario
Search Deals
Highest demand for flights based on searches. 15% potential increase in price ($84 potential increase over avg. RT price).
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Cheapest flight prices on average. 3% potential price decrease ($19 potential savings vs. average RT price).
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Average for round-trip flights in May 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 May 12, 2025.

This American Airlines deal was found by Cheapflights users on 5/11. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 5/2712:57 pmSAN - ONT
1 stop19h 59mAmerican Airlines
Sat 5/316:01 amONT - SAN
1 stop12h 25mAmerican Airlines
Deal found 5/11$367
This United Airlines deal was found by Cheapflights users on 5/11. 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.
Mon 6/95:50 pmSAN - ONT
1 stop18h 24mUnited Airlines
Mon 6/166:00 amONT - SAN
1 stop14h 36mUnited Airlines
Deal found 5/11$417
This Alaska Airlines deal was found by Cheapflights users on 5/11. 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.
Thu 5/228:15 amSAN - ONT
1 stop7h 35mAlaska Airlines
Fri 5/305:55 pmONT - SAN
1 stop6h 04mAlaska Airlines
Deal found 5/11$707

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 May 12, 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

Tue 5/27

12:57 pm-8:56 am

1 stop19h 59m

Ontario

Sat 5/31

6:01 am-6:26 pm

1 stop12h 25m

$367

San DiegoOntario

SAN - ONT

SANONT

San Diego

Mon 6/9

5:50 pm-12:14 pm

1 stop18h 24m

Ontario

Mon 6/16

6:00 am-8:36 pm

1 stop14h 36m

$417

San DiegoOntario

SAN - ONT

SANONT

San Diego

Thu 5/22

8:15 am-3:50 pm

1 stop7h 35m

Ontario

Fri 5/30

5:55 pm-11:59 pm

1 stop6h 04m

$707

San DiegoOntario

SAN - ONT

SANONT

San Diego

Wed 8/20

6:10 pm-11:53 pm

1 stop5h 43m

$172

San DiegoOntario

SAN - ONT

SANONT

San Diego

Tue 6/10

6:20 am-10:45 pm

1 stop16h 25m

$191

San DiegoOntario

SAN - ONT

SANONT

San Diego

Fri 5/23

12:57 pm-11:50 am

1 stop22h 53m

$249

Flights are sorted by cheapest round-trip flights first.

Deals found on 5/12

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 May.
ProviderPrice AccuracyTrust Score*
ExpediaPrice Accuracy1 starTrust Score*3 stars
FlightHubPrice Accuracy3 starsTrust Score*2 stars
CheapfaremartPrice Accuracy-Trust Score*1 star

*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 Expedia the most. Expedia 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, 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 May 12, 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.

Rainfall in Ontario by month

Plan your trip to Ontario by taking into account the average rainfall totals by month.

In terms of precipitation, rainfall in Ontario ranges from 0.1 - 3.4 inches per month. February is typically the wettest month, when rainfall can reach 3.4 in. June is typically the driest time to visit Ontario when rainfall is around 0.1 in.

Temperature in Ontario by month

Plan your trip to Ontario by taking into account the average temperature totals by month.

If weather is an important factor for your trip to Ontario, use this chart to help with planning. For those seeking warmer temperatures, August is the ideal time of year to visit, when temperatures reach an average of 78.8 F. Travelers looking to avoid the cold should look outside of December, when temperatures are typically at their lowest (around 53.6 F).

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 May 12, 2025.
Alaska Airlines
8.0
Very good
10,000 reviews

Boarding

8.1

Entertainment

7.1

Crew

8.5

Food

7.1

Overall

8.0

Comfort

7.9

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

Boarding

8.1

Entertainment

7.1

Crew

8.5

Food

7.1

Overall

8.0

Comfort

7.9

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
8,724 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Boarding

8.1

Entertainment

7.1

Crew

8.5

Food

7.1

Overall

8.0

Comfort

7.9

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

Boarding

8.1

Entertainment

7.1

Crew

8.5

Food

7.1

Overall

8.0

Comfort

7.9

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 flying from San Diego to Ontario round-trip?

    Our cheapest airline available from San Diego to Ontario is American Airlines. Our recent data shows that you can find tickets from as low as $367 on this airline. Additional options worth looking into are United Airlines and Alaska Airlines, starting at $417 and $707 round-trip. American Airlines is priced at 22% lower than the current average price of a flight leaving 3 months from now.

  • 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 $172 on Alaska Airlines. Other airlines that offer cheap prices include United Airlines from $191 and American Airlines from $249 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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Top airline flying from San Diego to Ontario

Discover the top airline that operate flights from San Diego 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 May 12, 2025.
AirlineCheapestAverageFlexibilityOn-time
Alaska AirlinesCheapest$281Average$412FlexibilityNo cancel feeOn-time75%

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