$59+ Cheap flights from Ontario to San Jose, CA (ONT - SJC)
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 10/26. Fares are subject to change and may not be available on all flights or dates of travel.
ONT — SJC
Aug 29 — Sep 51
Round-trip
1 adult, Economy
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Find cheap flights from Ontario to San Jose 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.Cheapflights Tip: The best prices from Ontario to San Jose are usually found in September or October, booked 25 days in advance, depart on a Thursday or Saturday and return on a Thursday
Cheap flight deals from Ontario to San Jose
Cheapest
Best
Last-minute
One-way
Cheapest flights from Ontario to San JoseExplore the most affordable flight options available from Ontario to San Jose. Find the lowest fares from popular airlines and budget airlines, with prices last updated on July 30, 2026.
Explore the most affordable flight options available from Ontario to San Jose. Find the lowest fares from popular airlines and budget airlines, with prices last updated on July 30, 2026.
This Southwest deal was found by Cheapflights users on 7/29. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 8/2410:55 am
ONT
- SJC
Nonstop1h 10m
Southwest
Wed 8/2612:20 pm
SJC
- ONT
Nonstop1h 15m
Southwest
Deal found 7/29![Southwest logo]()
$117
This Southwest deal was found by Cheapflights users on 7/29. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 9/54:40 pm
ONT
- SJC
Nonstop1h 20m
Southwest
Sun 9/67:45 am
SJC
- ONT
Nonstop1h 15m
Southwest
Deal found 7/29![Southwest logo]()
$122
This Southwest deal was found by Cheapflights users on 7/29. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 8/184:45 pm
ONT
- SJC
1 stop3h 20m
Southwest
Sat 8/225:00 pm
SJC
- ONT
Nonstop1h 20m
Southwest
Deal found 7/29![Southwest logo]()
$123
This Southwest deal was found by Cheapflights users on 7/30. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 8/244:50 pm
ONT
- SJC
1 stop4h 35m
Southwest
Thu 8/276:30 am
SJC
- ONT
Nonstop1h 20m
Southwest
Deal found 7/30![Southwest logo]()
$127
This Southwest deal was found by Cheapflights users on 7/30. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 9/14:45 pm
ONT
- SJC
1 stop3h 20m
Southwest
Fri 9/116:30 am
SJC
- ONT
Nonstop1h 20m
Southwest
Deal found 7/30![Southwest logo]()
$128
This FlightHub deal was found by Cheapflights users on 7/30. 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 FlightHub is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 8/273:40 pm
ONT
- SJC
1 stop21h 42m
Frontier
Mon 8/312:17 pm
SJC
- ONT
1 stop7h 10m
Frontier
Deal found 7/30![Frontier logo]()
$133
This Southwest deal was found by Cheapflights users on 7/30. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 9/32:40 pm
ONT
- SJC
1 stop6h 50m
Southwest
Thu 9/107:55 am
SJC
- ONT
1 stop3h 30m
Southwest
Deal found 7/30![Southwest logo]()
$137
This Southwest deal was found by Cheapflights users on 7/29. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 8/254:45 pm
ONT
- SJC
1 stop3h 20m
Southwest
Tue 9/11:45 pm
SJC
- ONT
2 stops7h 10m
Southwest
Deal found 7/29![Southwest logo]()
$138
This Southwest deal was found by Cheapflights users on 7/29. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 8/295:50 am
ONT
- SJC
2 stops6h 50m
Southwest
Tue 9/11:45 pm
SJC
- ONT
2 stops7h 10m
Southwest
Deal found 7/29![Southwest logo]()
$147
Best flights from Ontario to San JoseDiscover carefully curated flight deals from Ontario to San Jose that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated July 30, 2026.
Discover carefully curated flight deals from Ontario to San Jose that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated July 30, 2026.
This Southwest deal was found by Cheapflights users on 7/29. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 9/54:40 pm
ONT
- SJC
Nonstop1h 20m
Southwest
Sun 9/67:45 am
SJC
- ONT
Nonstop1h 15m
Southwest
Deal found 7/29![Southwest logo]()
$122
This Southwest 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 9/55:50 am
ONT
- SJC
2 stops6h 05m
Southwest
Mon 9/76:30 am
SJC
- ONT
Nonstop1h 20m
Southwest
Deal found 7/27![Southwest logo]()
$132
This Southwest deal was found by Cheapflights users on 7/25. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 9/84:45 pm
ONT
- SJC
1 stop3h 25m
Southwest
Tue 9/158:00 am
SJC
- ONT
1 stop6h 05m
Southwest
Deal found 7/25![Southwest logo]()
$132
This Southwest deal was found by Cheapflights users on 7/26. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 9/94:45 pm
ONT
- SJC
1 stop3h 25m
Southwest
Wed 9/168:40 am
SJC
- ONT
2 stops8h 55m
Southwest
Deal found 7/26![Southwest logo]()
$138
This Southwest deal was found by Cheapflights users on 7/29. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 9/2610:15 am
ONT
- SJC
2 stops7h 50m
Southwest
Mon 9/283:10 pm
SJC
- ONT
2 stops6h 55m
Southwest
Deal found 7/29![Southwest logo]()
$147
This Southwest deal was found by Cheapflights users on 7/25. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 10/28:40 am
ONT
- SJC
2 stops4h 50m
Southwest
Sat 10/316:25 am
SJC
- ONT
Nonstop1h 20m
Southwest
Deal found 7/25![Southwest logo]()
$191
This Southwest deal was found by Cheapflights users on 7/26. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 8/202:40 pm
ONT
- SJC
2 stops6h 30m
Southwest
Sun 8/234:10 pm
SJC
- ONT
2 stops6h 10m
Southwest
Deal found 7/26![Southwest logo]()
$248
This Southwest deal was found by Cheapflights users on 7/25. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 8/285:40 am
ONT
- SJC
2 stops6h 15m
Southwest
Thu 9/32:40 pm
SJC
- ONT
2 stops7h 25m
Southwest
Deal found 7/25![Southwest logo]()
$265
This Southwest deal was found by Cheapflights users on 7/29. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 8/172:40 pm
ONT
- SJC
2 stops6h 55m
Southwest
Thu 8/206:30 am
SJC
- ONT
Nonstop1h 20m
Southwest
Deal found 7/29![Southwest logo]()
$273
This Southwest 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 8/155:50 am
ONT
- SJC
2 stops6h 50m
Southwest
Thu 8/2010:55 am
SJC
- ONT
Nonstop1h 15m
Southwest
Deal found 7/27![Southwest logo]()
$273
Last-minute flights from Ontario to San JoseDiscover last-minute flight deals from Ontario to San Jose. Data last updated July 30, 2026 and is based on user searches.
Discover last-minute flight deals from Ontario to San Jose. Data last updated July 30, 2026 and is based on user searches.
This Southwest deal was found by Cheapflights users on 7/29. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 8/184:45 pm
ONT
- SJC
1 stop3h 20m
Southwest
Sat 8/225:00 pm
SJC
- ONT
Nonstop1h 20m
Southwest
Deal found 7/29![Southwest logo]()
$123
This Southwest deal was found by Cheapflights users on 7/29. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 8/2410:55 am
ONT
- SJC
Nonstop1h 10m
Southwest
Wed 8/2612:20 pm
SJC
- ONT
Nonstop1h 15m
Southwest
Deal found 7/29![Southwest logo]()
$117
This Southwest deal was found by Cheapflights users on 7/30. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 8/244:50 pm
ONT
- SJC
1 stop4h 35m
Southwest
Thu 8/276:30 am
SJC
- ONT
Nonstop1h 20m
Southwest
Deal found 7/30![Southwest logo]()
$127
This Southwest deal was found by Cheapflights users on 7/29. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 8/254:45 pm
ONT
- SJC
1 stop3h 20m
Southwest
Tue 9/11:45 pm
SJC
- ONT
2 stops7h 10m
Southwest
Deal found 7/29![Southwest logo]()
$138
This FlightHub deal was found by Cheapflights users on 7/30. 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 FlightHub is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 8/273:40 pm
ONT
- SJC
1 stop21h 42m
Frontier
Mon 8/312:17 pm
SJC
- ONT
1 stop7h 10m
Frontier
Deal found 7/30![Frontier logo]()
$133
This Southwest deal was found by Cheapflights users on 7/29. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 8/286:00 am
ONT
- SJC
Nonstop1h 15m
Southwest
Mon 8/3110:55 am
SJC
- ONT
Nonstop1h 15m
Southwest
Deal found 7/29![Southwest logo]()
$176
This Southwest deal was found by Cheapflights users on 7/29. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 8/295:50 am
ONT
- SJC
2 stops6h 50m
Southwest
Tue 9/11:45 pm
SJC
- ONT
2 stops7h 10m
Southwest
Deal found 7/29![Southwest logo]()
$147
One-way flights from Ontario to San JoseSearch for one-way flight options from Ontario to San Jose. Find affordable one-way fares based on user searches. Data last updated July 30, 2026.
Search for one-way flight options from Ontario to San Jose. Find affordable one-way fares based on user searches. Data last updated July 30, 2026.
This Southwest 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 8/206:00 am
ONT
- SJC
Nonstop1h 15m
Southwest
Deal found 7/28![Southwest logo]()
$59
This Southwest 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 8/264:45 pm
ONT
- SJC
1 stop3h 20m
Southwest
Deal found 7/27![Southwest logo]()
$64
This Super.com deal was found by Cheapflights users on 7/30. 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 Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 9/33:40 pm
ONT
- SJC
1 stop21h 42m
Frontier
Deal found 7/30![Frontier logo]()
$65
This Super.com deal was found by Cheapflights users on 7/30. 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 Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 9/288:00 am
ONT
- SJC
1 stop4h 43m
Frontier
Deal found 7/30![Frontier logo]()
$76
This Southwest deal was found by Cheapflights users on 7/29. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 9/115:40 am
ONT
- SJC
2 stops6h 15m
Southwest
Deal found 7/29![Southwest logo]()
$79
This Super.com deal was found by Cheapflights users on 7/30. 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 Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 9/53:40 pm
ONT
- SJC
1 stop20h 27m
Frontier
Deal found 7/30![Frontier logo]()
$82
This Kiwi.com deal was found by Cheapflights users on 7/26. 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 9/2311:45 am
ONT
- SJC
2 stops32h 08m
Frontier
Deal found 7/26![Frontier logo]()
$96
This Kiwi.com deal was found by Cheapflights users on 7/30. 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 9/3011:45 am
ONT
- SJC
2 stops32h 08m
Frontier
Deal found 7/30![Frontier logo]()
$97
This Kiwi.com deal was found by Cheapflights users on 7/25. 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 8/266:00 am
ONT
- SJC
2 stops37h 19m
Frontier
Deal found 7/25![Frontier logo]()
$98
This Kiwi.com deal was found by Cheapflights users on 7/30. 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.
Sun 9/272:30 pm
ONT
- SJC
1 stop7h 22m
Frontier
Deal found 7/30![Frontier logo]()
$103
Find flight deals from Ontario to San Jose
Discover tips and strategies to find the most affordable flight options for your journey from Ontario (ONT) to San Jose (SJC). 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 30, 2026.
Most accurate provider | FlightHub 3 stars |
|---|---|
Most trusted provider | FlightHub 3 stars |
Round-trip from | $117 (Southwest) |
One-way from | $59 (Southwest) |
Popular in | May |
Cheapest in | September |
Average price | $358 |
Good round-trip deal | $276 or less |
Good one-way deal | $90 or less |
Cheapflights Fare Finder
Customize your flight search to find flights from Ontario to San Jose 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 30, 2026.
Use the filters below to find and compare flights from Ontario to San Jose that are best for you.
Fly from
Fly to
Route
Depart
Return
Cheapest round-trip
Quickest round-trip
OntarioSan Jose
ONT - SJC
ONTSJC
Ontario
Sat 9/5
4:40 pm-6:00 pm
Nonstop1h 20m
San Jose
Sun 9/6
7:45 am-9:00 am
Nonstop1h 15m
$122
OntarioSan Jose
ONT - SJC
ONTSJC
Ontario
Sat 9/5
5:50 am-11:55 am
2 stops6h 05m
San Jose
Mon 9/7
6:30 am-7:50 am
Nonstop1h 20m
$132
OntarioSan Jose
ONT - SJC
ONTSJC
Ontario
Tue 9/8
4:45 pm-8:10 pm
1 stop3h 25m
San Jose
Tue 9/15
8:00 am-2:05 pm
1 stop6h 05m
$132
OntarioSan Jose
ONT - SJC
ONTSJC
Ontario
Wed 9/9
4:45 pm-8:10 pm
1 stop3h 25m
San Jose
Wed 9/16
8:40 am-5:35 pm
2 stops8h 55m
$138
OntarioSan Jose
ONT - SJC
ONTSJC
Ontario
Sat 9/26
10:15 am-6:05 pm
2 stops7h 50m
San Jose
Mon 9/28
3:10 pm-10:05 pm
2 stops6h 55m
$147
OntarioSan Jose
ONT - SJC
ONTSJC
Ontario
Fri 10/2
8:40 am-1:30 pm
2 stops4h 50m
San Jose
Sat 10/31
6:25 am-7:45 am
Nonstop1h 20m
$191
OntarioSan Jose
ONT - SJC
ONTSJC
Ontario
Thu 8/20
2:40 pm-9:10 pm
2 stops6h 30m
San Jose
Sun 8/23
4:10 pm-10:20 pm
2 stops6h 10m
$248
OntarioSan Jose
ONT - SJC
ONTSJC
Ontario
Fri 8/28
5:40 am-11:55 am
2 stops6h 15m
San Jose
Thu 9/3
2:40 pm-10:05 pm
2 stops7h 25m
$265
OntarioSan Jose
ONT - SJC
ONTSJC
Ontario
Mon 8/17
2:40 pm-9:35 pm
2 stops6h 55m
San Jose
Thu 8/20
6:30 am-7:50 am
Nonstop1h 20m
$273
OntarioSan Jose
ONT - SJC
ONTSJC
Ontario
Sat 8/15
5:50 am-12:40 pm
2 stops6h 50m
San Jose
Thu 8/20
10:55 am-12:10 pm
Nonstop1h 15m
$273
Showing 1-10 of 19 resultsSorted by cheapest first
Compare providers for flights from Ontario to San Jose
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 Jose in July.
| Provider | Price Accuracy | Trust Score* |
|---|---|---|
| Price Accuracy1 star | Trust Score*3 stars | |
| Price Accuracy3 stars | Trust Score*3 stars | |
| Price Accuracy- | Trust Score*1 star |
- Most accurate provider: When it comes to deals on Ontario-San Jose, California flights, users find the pricing of FlightHub to be most consistent on Cheapflights vs. FlightHub Users can find the same prices on Ontario-San Jose, California flight deals on Cheapflights vs. FlightHub >95% of the time. Price accuracy is based on data collected from Ontario-San Jose, California flight searches over the past month and is updated monthly.
- Most trusted provider: When it comes to deals on Ontario-San Jose, California 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 Jose, California 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 Jose
Have a flexible travel schedule? Discover the best time to fly to San Jose from Ontario with our price prediction graph.
ONT-SJC
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 Ontario to San Jose
How far ahead should I book a flight from Ontario to San Jose, California?
To ensure you get the cheapest price possible for a flight from Ontario to San Jose, California, you should look to book at least 90 days in advance of your intended travel date. The price of your flight may increase if you delay and leave booking until a week or so before departure.
What is the cheapest month to book a flight from Ontario to San Jose, California?
Currently, September is the cheapest month in which you can book a flight from Ontario to San Jose, California (average of $248). Flying from Ontario to San Jose, California in May is currently the most expensive (average of $547). 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 ONT to SJC?
Find hourly flight availability from Ontario to San Jose. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated July 30, 2026.
It’s optimal to fly from Ontario to San Jose, California at noon. By choosing this option you can save up to 16% on the cost of your flight, compared to a flight in the morning.
What is the cheapest day to fly from Ontario to San Jose, California?
Use this chart to determine the cheapest time to fly round-trip from Ontario to San Jose. Price data was last updated on July 25, 2026.
Travelers seeking maximum savings on their Ontario to San Jose, California flight should consider departing on Wednesday at noon when fares are most often at their lowest. Monday evenings flights should be avoided if possible as fares are typically the most expensive at this time.
The best insider tips for Ontario to San Jose flights
AI-powered summary based on content written by travel experts. AI can make mistakes.
Cheapflights partnered with top experts to bring you the best recommendations for your Ontario to San Jose trip
Our travel experts
Reviews of airlines servicing San Jose
Get insights into the airlines that provide service to San Jose. 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 San Jose. Reviews last updated July 30, 2026.
Peruse reviews from past customers who have flown with Southwest and Frontier from Ontario to San Jose to help guide your decision. You can also see how each airline stacks up in terms of entertainment options, comfort, food, crew/service, and boarding process.
Overall
8.0
Crew
8.6
Boarding
8.1
Comfort
8.0
Food
7.0
Entertainment
7.5
Reviews
1 / 20
8.0
ExcellentWalter,Aug 2025
OAK - SAN
Overall
8.0
Crew
8.6
Boarding
8.1
Comfort
8.0
Food
7.0
Entertainment
7.5
Reviews
1 / 20
8.0
ExcellentWalter,Aug 2025
OAK - SAN
Overall
8.0
Crew
8.6
Boarding
8.1
Comfort
8.0
Food
7.0
Entertainment
7.5
Reviews
1 / 20
8.0
ExcellentWalter,Aug 2025
OAK - SAN
Related info for your journey
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Ontario and San Jose flights
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Top 2 airlines flying from Ontario to San Jose
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| Airline | Cheapest | Average | Flexibility | On-time |
|---|---|---|---|---|
| Cheapest$29 | Average$110 | FlexibilityNo cancel fee | On-time62% | |
| Cheapest$124 | Average$328 | FlexibilityNo cancel fee | On-time63% |