$44+ Cheap flights from Ontario to San Diego (ONT - SAN)
This is the cheapest round-trip flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 12/1. Fares are subject to change and may not be available on all flights or dates of travel.
ONT — SAN
Dec 4 — Dec 111
Round-trip
1 adult, Economy
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Find cheap flights from Ontario to San Diego with Cheapflights
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
We find the providers serving your travel needs. Choose up to four travel providers to compare side-by-side for flights, hotels, or car rentals.3. Compare prices and book
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 Ontario to San Diego
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Best
Last-minute
One-way
Cheapest flights from Ontario to San DiegoExplore the most affordable flight options available from Ontario to San Diego. Find the lowest fares from popular airlines and budget airlines, with prices last updated on November 4, 2026.
Explore the most affordable flight options available from Ontario to San Diego. Find the lowest fares from popular airlines and budget airlines, with prices last updated on November 4, 2026.
This Mytrip deal was found by Cheapflights users on 11/2. 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 Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 12/98:44 am -
2 stops9h 32m
Wed 12/168:57 am -
1 stop9h 34m
Deal found 11/2![Frontier logo]()
$111
This Kiwi.com deal was found by Cheapflights users on 10/31. 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.
Sat 11/2110:47 pm -
1 stop9h 08m
Thu 11/2611:26 am -
1 stop8h 10m
Deal found 10/31![Frontier logo]()
$114
This Mytrip deal was found by Cheapflights users on 11/3. 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 Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 12/111:30 am -
1 stop12h 27m
Tue 12/88:57 am -
1 stop9h 34m
Deal found 11/3![Frontier logo]()
$115
This Mytrip deal was found by Cheapflights users on 11/3. 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 Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 12/311:30 am -
1 stop12h 27m
Thu 12/1011:14 am -
1 stop13h 06m
Deal found 11/3![Frontier logo]()
$120
This Mytrip deal was found by Cheapflights users on 11/2. 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 Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 12/411:30 am -
1 stop12h 27m
Mon 12/78:57 am -
1 stop9h 34m
Deal found 11/2![Frontier logo]()
$123
This Mytrip deal was found by Cheapflights users on 11/3. 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 Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 12/711:30 am -
1 stop12h 28m
Sat 12/126:30 am -
1 stop15h 47m
Deal found 11/3![Frontier logo]()
$128
This Mytrip deal was found by Cheapflights users on 11/2. 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 Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 12/1111:30 am -
1 stop12h 28m
Wed 12/168:57 am -
1 stop9h 34m
Deal found 11/2![Frontier logo]()
$137
This Mytrip deal was found by Cheapflights users on 10/31. 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 Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 12/1411:00 am -
2 stops23h 19m
Tue 12/297:53 pm -
1 stop11h 14m
Deal found 10/31![Frontier logo]()
$140
Best flights from Ontario to San DiegoDiscover carefully curated flight deals from Ontario to San Diego that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated November 4, 2026.
Discover carefully curated flight deals from Ontario to San Diego that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated November 4, 2026.
This Mytrip deal was found by Cheapflights users on 10/31. 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 Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 12/1411:00 am -
2 stops23h 19m
Tue 12/297:53 pm -
1 stop11h 14m
Deal found 10/31![Frontier logo]()
$140
This Frontier deal was found by Cheapflights users on 11/1. 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.
Mon 12/711:30 am -
1 stop12h 28m
Mon 12/148:57 am -
1 stop9h 34m
Deal found 11/1![Frontier logo]()
$163
This Mytrip deal was found by Cheapflights users on 11/2. 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 Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 12/2010:33 pm -
2 stops15h 17m
Thu 12/247:53 pm -
1 stop11h 14m
Deal found 11/2![Frontier logo]()
$166
This Mytrip deal was found by Cheapflights users on 11/4. 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 Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 12/158:44 am -
2 stops24h 29m
Sat 12/193:04 pm -
2 stops20h 25m
Deal found 11/4![Frontier logo]()
$177
This Mytrip deal was found by Cheapflights users on 11/1. 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 Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 11/302:01 pm -
2 stops28h 09m
Mon 12/78:57 am -
1 stop9h 34m
Deal found 11/1![Frontier logo]()
$181
This Frontier deal was found by Cheapflights users on 11/1. 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.
Thu 12/1711:32 am -
1 stop12h 26m
Mon 12/211:14 pm -
1 stop7h 28m
Deal found 11/1![Frontier logo]()
$184
Last-minute flights from Ontario to San DiegoDiscover last-minute flight deals from Ontario to San Diego. Data last updated November 4, 2026 and is based on user searches.
Discover last-minute flight deals from Ontario to San Diego. Data last updated November 4, 2026 and is based on user searches.
This Kiwi.com deal was found by Cheapflights users on 10/31. 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.
Sat 11/2110:47 pm -
1 stop9h 08m
Thu 11/2611:26 am -
1 stop8h 10m
Deal found 10/31![Frontier logo]()
$114
This Mytrip deal was found by Cheapflights users on 11/3. 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 Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 12/111:30 am -
1 stop12h 27m
Tue 12/88:57 am -
1 stop9h 34m
Deal found 11/3![Frontier logo]()
$115
This Mytrip deal was found by Cheapflights users on 11/3. 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 Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 12/311:30 am -
1 stop12h 27m
Thu 12/1011:14 am -
1 stop13h 06m
Deal found 11/3![Frontier logo]()
$120
This Mytrip deal was found by Cheapflights users on 11/2. 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 Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 12/411:30 am -
1 stop12h 27m
Mon 12/78:57 am -
1 stop9h 34m
Deal found 11/2![Frontier logo]()
$123
This Mytrip deal was found by Cheapflights users on 11/3. 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 Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 12/711:30 am -
1 stop12h 28m
Sat 12/126:30 am -
1 stop15h 47m
Deal found 11/3![Frontier logo]()
$128
This Mytrip deal was found by Cheapflights users on 11/2. 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 Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 12/98:44 am -
2 stops9h 32m
Wed 12/168:57 am -
1 stop9h 34m
Deal found 11/2![Frontier logo]()
$111
This Mytrip deal was found by Cheapflights users on 11/2. 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 Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 12/1111:30 am -
1 stop12h 28m
Wed 12/168:57 am -
1 stop9h 34m
Deal found 11/2![Frontier logo]()
$137
This Mytrip deal was found by Cheapflights users on 10/31. 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 Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 12/1411:00 am -
2 stops23h 19m
Tue 12/297:53 pm -
1 stop11h 14m
Deal found 10/31![Frontier logo]()
$140
One-way flights from Ontario to San DiegoSearch for one-way flight options from Ontario to San Diego. Find affordable one-way fares based on user searches. Data last updated November 4, 2026.
Search for one-way flight options from Ontario to San Diego. Find affordable one-way fares based on user searches. Data last updated November 4, 2026.
This Kiwi.com deal was found by Cheapflights users on 11/3. 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 12/17:06 pm -
1 stop23h 04m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 11/3![Frontier logo]()
$44
This Kiwi.com deal was found by Cheapflights users on 10/30. 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 11/258:15 am -
1 stop23h 40m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 10/30![Frontier logo]()
$54
This Kiwi.com deal was found by Cheapflights users on 10/31. 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 2/16:27 pm -
1 stop20h 11m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 10/31![Frontier logo]()
$55
This Kiwi.com deal was found by Cheapflights users on 11/1. 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.
Sat 12/1910:51 pm -
1 stop13h 33m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 11/1![Frontier logo]()
$60
This Frontier deal was found by Cheapflights users on 11/2. 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.
Fri 1/298:02 am -
1 stop6h 36m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 11/2![Frontier logo]()
$62
This Booking.com deal was found by Cheapflights users on 10/31. 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 Booking.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 11/185:07 pm -
1 stop26h 28m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 10/31![Frontier logo]()
$70
This Kiwi.com deal was found by Cheapflights users on 11/2. 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 12/711:00 am -
2 stops31h 16m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 11/2![Frontier logo]()
$75
This Booking.com deal was found by Cheapflights users on 11/1. 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 Booking.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 12/88:44 am -
2 stops9h 32m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 11/1![Frontier logo]()
$81
This Frontier deal was found by Cheapflights users on 11/2. 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.
Fri 12/411:30 am -
1 stop12h 27m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 11/2![Frontier logo]()
$82
Find flight deals from Ontario to San Diego
Discover tips and strategies to find the most affordable flight options for your journey from Ontario (ONT) to San Diego (SAN). 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 November 4, 2026.
Most accurate provider | FlightHub 3 stars |
|---|---|
Most trusted provider | FlightHub 3 stars |
Round-trip from | $111 (Mytrip) |
One-way from | $44 (Kiwi.com) |
Popular in | January |
Cheapest in | February |
Average price | $309 |
Cheapflights Fare Finder
Customize your flight search to find flights from Ontario to San Diego 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 7,457,451 searches. Data last updated November 4, 2026.
Use the filters below to find and compare flights from Ontario to San Diego that are best for you.
Fly from
Fly to
Route
Depart
Return
Cheapest round-trip
OntarioSan Diego
ONT Ontario - SAN San Diego
ONTSAN
Ontario
Tue 12/1
2:00 pm-11:37 am
1 stop21h 37m
San Diego
Wed 12/31
12:00 am-12:00 am
Nonstop0h 00m
$49
OntarioSan Diego
ONT Ontario - SAN San Diego
ONTSAN
Ontario
Wed 11/25
8:15 am-7:55 am
1 stop23h 40m
San Diego
Wed 12/31
12:00 am-12:00 am
Nonstop0h 00m
$54
OntarioSan Diego
ONT Ontario - SAN San Diego
ONTSAN
Ontario
Mon 2/1
6:27 pm-2:38 pm
1 stop20h 11m
San Diego
Wed 12/31
12:00 am-12:00 am
Nonstop0h 00m
$55
OntarioSan Diego
ONT Ontario - SAN San Diego
ONTSAN
Ontario
Mon 1/25
11:42 am-11:58 pm
1 stop12h 16m
San Diego
Wed 12/31
12:00 am-12:00 am
Nonstop0h 00m
$82
OntarioSan Diego
ONT Ontario - SAN San Diego
ONTSAN
Ontario
Mon 12/14
11:00 am-10:19 am
2 stops23h 19m
San Diego
Tue 12/29
7:53 pm-7:07 am
1 stop11h 14m
$140
Quickest round-trip
OntarioSan Diego
ONT Ontario - SAN San Diego
ONTSAN
Ontario
Thu 11/12
12:01 pm-6:38 pm
1 stop6h 37m
San Diego
Wed 12/31
12:00 am-12:00 am
Nonstop0h 00m
$153
OntarioSan Diego
ONT Ontario - SAN San Diego
ONTSAN
Ontario
Mon 12/7
11:30 am-11:58 pm
1 stop12h 28m
San Diego
Mon 12/14
8:57 am-6:31 pm
1 stop9h 34m
$163
OntarioSan Diego
ONT Ontario - SAN San Diego
ONTSAN
Ontario
Sun 12/20
10:33 pm-1:50 pm
2 stops15h 17m
San Diego
Thu 12/24
7:53 pm-7:07 am
1 stop11h 14m
$166
OntarioSan Diego
ONT Ontario - SAN San Diego
ONTSAN
Ontario
Tue 12/15
8:44 am-9:13 am
2 stops24h 29m
San Diego
Sat 12/19
3:04 pm-11:29 am
2 stops20h 25m
$177
OntarioSan Diego
ONT Ontario - SAN San Diego
ONTSAN
Ontario
Mon 11/30
2:01 pm-6:10 pm
2 stops28h 09m
San Diego
Mon 12/7
8:57 am-6:31 pm
1 stop9h 34m
$181
Showing 1-10 of 12 resultsSorted by cheapest first
Compare providers for flights from Ontario to San Diego
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 Ontario to San Diego in November.
| Provider | Price Accuracy | Trust Score* |
|---|---|---|
| Price Accuracy1 star | Trust Score*3 stars | |
| Price Accuracy3 stars | Trust Score*3 stars | |
| Price Accuracy2 stars | Trust Score*3 stars |
- Most accurate provider: When it comes to deals on Ontario-San Diego flights, users find the pricing of FlightHub to be most consistent on Cheapflights vs. FlightHub Users can find the same prices on Ontario-San Diego flight deals on Cheapflights vs. FlightHub >95% of the time. Price accuracy is based on data collected from Ontario-San Diego flight searches over the past month and is updated monthly.
- Most trusted provider: When it comes to deals on Ontario-San Diego 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 Ontario-San Diego 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 Ontario to San Diego
Have a flexible travel schedule? Discover the best time to fly to San Diego from Ontario with our price prediction graph.
ONT-SAN
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.
Related info for your journey
Find useful and relevant information for your journey from Ontario to San Diego. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.
Traveling to a place near San Diego?
Book flights to San Diego if you plan to visit one of these locationsEl Cajon
National City
Chula Vista
San Ysidro
Poway
Coronado
La Mesa
Julian
Santee
Lemon Grove
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