$119+ 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 2/6. Fares are subject to change and may not be available on all flights or dates of travel.
SAN — ONT
Jan 14 — Jan 211
1 adult, Economy
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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
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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 OntarioExplore 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 December 15, 2025.
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 December 15, 2025.
This Kiwi.com deal was found by Cheapflights users on 12/13. 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 12/227:21 pmSAN - ONT
1 stop25h 56mFrontier
Fri 1/210:12 pmONT - SAN
1 stop17h 40mFrontier
Deal found 12/13![Frontier logo]()
$428
This Kiwi.com deal was found by Cheapflights users on 12/13. 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 12/166:34 amSAN - ONT
2 stops38h 43mFrontier
Thu 12/186:17 pmONT - SAN
1 stop18h 21mFrontier
Deal found 12/13![Frontier logo]()
$584
This Kiwi.com deal was found by Cheapflights users on 12/14. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 12/143:18 pmSAN - ONT
1 stop22h 46mFrontier
Mon 12/155:18 pmONT - SAN
2 stops53h 28mFrontier
Deal found 12/14![Frontier logo]()
$588
This United Airlines deal was found by Cheapflights users on 12/12. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 12/166:15 amSAN - ONT
1 stop16h 34mUnited Airlines
Thu 12/186:00 amONT - SAN
1 stop7h 02mUnited Airlines
Deal found 12/12![United Airlines logo]()
$865
This Kiwi.com deal was found by Cheapflights users on 12/15. 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.
Wed 12/176:25 amSAN - ONT
2 stops26h 28mFrontier
Sat 12/205:16 pmONT - SAN
1 stop18h 55mFrontier
Deal found 12/15![Frontier logo]()
$875
This United Airlines deal was found by Cheapflights users on 12/15. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 12/266:15 amSAN - ONT
1 stop11h 28mUnited Airlines
Sun 12/286:00 amONT - SAN
1 stop14h 48mUnited Airlines
Deal found 12/15![United Airlines logo]()
$889
This United Airlines deal was found by Cheapflights users on 12/13. 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 12/155:45 pmSAN - ONT
1 stop18h 32mUnited Airlines
Tue 12/166:41 pmONT - SAN
1 stop15h 59mUnited Airlines
Deal found 12/13![United Airlines logo]()
$908
This United Airlines deal was found by Cheapflights users on 12/15. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 12/264:00 pmSAN - ONT
1 stop6h 41mUnited Airlines
Fri 1/26:39 pmONT - SAN
1 stop5h 36mUnited Airlines
Deal found 12/15![United Airlines logo]()
$912
This United Airlines deal was found by Cheapflights users on 12/13. 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.
Fri 12/265:40 pmSAN - ONT
1 stop5h 01mUnited Airlines
Sat 12/2710:42 amONT - SAN
1 stop8h 01mUnited Airlines
Deal found 12/13![United Airlines logo]()
$938
This Alaska Airlines deal was found by Cheapflights users on 12/13. 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 12/168:10 amSAN - ONT
1 stop13h 33mMultiple Airlines
Thu 12/186:05 pmONT - SAN
1 stop6h 02mMultiple Airlines
Deal found 12/13![Multiple Airlines logo]()
$1,087
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 December 15, 2025.
Most accurate provider | eDreams 3 stars |
|---|---|
Most trusted provider | eDreams 3 stars |
Round-trip from | $139 (Kiwi.com) |
One-way from | $119 (Alaska Airlines) |
Popular in | March |
Cheapest in | July |
Average price | $201 |
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 December 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
Sat 1/10
9:44 am-2:26 pm
1 stop4h 42m
Ontario
Sat 1/17
7:15 am-6:13 pm
1 stop10h 58m
$139
San DiegoOntario
SAN - ONT
SANONT
San Diego
Thu 1/29
2:56 pm-7:53 pm
1 stop4h 57m
Ontario
Thu 2/5
6:20 am-12:08 am
1 stop17h 48m
$141
San DiegoOntario
SAN - ONT
SANONT
San Diego
Mon 1/12
4:47 pm-10:59 pm
1 stop30h 12m
Ontario
Mon 1/19
10:18 pm-11:31 pm
2 stops25h 13m
$179
San DiegoOntario
SAN - ONT
SANONT
San Diego
Wed 2/18
6:15 am-10:44 pm
1 stop16h 29m
Ontario
Wed 2/25
6:14 am-1:20 pm
1 stop7h 06m
$226
San DiegoOntario
SAN - ONT
SANONT
San Diego
Fri 1/23
6:15 am-11:56 pm
1 stop17h 41m
Ontario
Fri 1/30
6:00 am-11:09 pm
1 stop17h 09m
$226
San DiegoOntario
SAN - ONT
SANONT
San Diego
Sat 1/17
6:15 am-8:36 pm
1 stop14h 21m
Ontario
Sat 1/24
11:53 am-8:58 pm
1 stop9h 05m
$226
San DiegoOntario
SAN - ONT
SANONT
San Diego
Sat 3/14
6:15 am-11:32 pm
1 stop17h 17m
Ontario
Wed 3/25
6:00 am-9:36 pm
1 stop15h 36m
$246
San DiegoOntario
SAN - ONT
SANONT
San Diego
Mon 2/9
6:15 am-11:56 pm
1 stop17h 41m
Ontario
Fri 2/27
6:14 am-11:03 pm
1 stop16h 49m
$246
San DiegoOntario
SAN - ONT
SANONT
San Diego
Thu 1/15
4:01 pm-11:56 pm
1 stop7h 55m
Ontario
Thu 1/22
6:00 am-8:58 pm
1 stop14h 58m
$275
San DiegoOntario
SAN - ONT
SANONT
San Diego
Fri 2/6
8:42 pm-3:08 pm
1 stop18h 26m
$119
Showing 1-10 of 20 results
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 December.
| Provider | Price Accuracy | Trust Score* |
|---|---|---|
| Price Accuracy2 stars | Trust Score*3 stars | |
| Price Accuracy3 stars | Trust Score*1 star | |
| Price Accuracy3 stars | Trust Score*3 stars |
- Most accurate provider: When it comes to deals on San Diego-Ontario flights, users find the pricing of eDreams to be most consistent on Cheapflights vs. eDreams Users can find the same prices on San Diego-Ontario flight deals on Cheapflights vs. eDreams >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 eDreams the most. eDreams 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, January is the cheapest month in which you can book a flight from San Diego to Ontario (average of $102). 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.
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 December 15, 2025.
It’s optimal to fly from San Diego to Ontario in the evening. By choosing this option you can save up to 21% on the cost of your flight, compared to a flight in the afternoon.