$59+ Cheap flights from Ontario to San Jose, CA (ONT - SJC)
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 10/1. Fares are subject to change and may not be available on all flights or dates of travel.
ONT — SJC
Oct 8 — Oct 151
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 October or September, booked 61 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 September 8, 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 September 8, 2026.
This Southwest deal was found by Cheapflights users on 9/8. 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 10/66:25 pm -
Nonstop1h 10m
Tue 10/137:25 am -
Nonstop1h 15m
Deal found 9/8![Southwest logo]()
$117
This Southwest deal was found by Cheapflights users on 9/8. 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 10/39:25 am -
1 stop6h 40m
Mon 10/56:45 am -
Nonstop1h 20m
Deal found 9/8![Southwest logo]()
$127
This Trip.com deal was found by Cheapflights users on 9/8. 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 Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 10/18:00 am -
1 stop4h 43m
Mon 10/51:38 pm -
1 stop19h 31m
Deal found 9/8![Frontier logo]()
$128
This Booking.com deal was found by Cheapflights users on 9/8. 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.
Thu 10/158:35 pm -
1 stop16h 45m
Mon 10/199:02 pm -
1 stop19h 28m
Deal found 9/8![Frontier logo]()
$130
This CheapOair deal was found by Cheapflights users on 9/8. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/72:30 pm -
1 stop22h 50m
Mon 10/129:02 pm -
1 stop13h 29m
Deal found 9/8![Frontier logo]()
$133
This Southwest deal was found by Cheapflights users on 9/4. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 10/93:55 pm -
Nonstop1h 10m
Sat 10/104:35 pm -
Nonstop1h 25m
Deal found 9/4![Southwest logo]()
$134
This Southwest deal was found by Cheapflights users on 9/4. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 10/245:30 am -
2 stops6h 40m
Tue 10/278:05 am -
2 stops7h 30m
Deal found 9/4![Southwest logo]()
$147
This Southwest deal was found by Cheapflights users on 9/8. 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 11/68:35 am -
1 stop5h 40m
Mon 11/96:30 am -
Nonstop1h 15m
Deal found 9/8![Southwest logo]()
$154
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 September 8, 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 September 8, 2026.
This Southwest deal was found by Cheapflights users on 9/8. 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 11/68:35 am -
1 stop5h 40m
Mon 11/96:30 am -
Nonstop1h 15m
Deal found 9/8![Southwest logo]()
$154
This Alaska Airlines deal was found by Cheapflights users on 9/6. 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.
Fri 11/67:13 pm -
1 stop18h 03m
Sun 11/86:17 am -
1 stop16h 49m
Deal found 9/6![Alaska Airlines logo]()
$243
This Southwest deal was found by Cheapflights users on 9/3. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 2/197:40 am -
1 stop4h 55m
Sat 2/201:35 pm -
2 stops7h 15m
Deal found 9/3![Southwest logo]()
$206
This Alaska Airlines deal was found by Cheapflights users on 9/4. 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 Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 12/124:00 pm -
1 stop6h 12m
Sun 12/138:00 am -
1 stop14h 39m
Deal found 9/4![Alaska Airlines logo]()
$283
This Southwest deal was found by Cheapflights users on 9/8. 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 10/93:55 pm -
Nonstop1h 10m
Sun 10/116:35 am -
Nonstop1h 20m
Deal found 9/8![Southwest logo]()
$265
This Southwest deal was found by Cheapflights users on 9/4. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 10/179:25 am -
2 stops5h 45m
Sat 10/174:35 pm -
Nonstop1h 25m
Deal found 9/4![Southwest logo]()
$270
This Southwest deal was found by Cheapflights users on 9/4. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 10/105:30 am -
2 stops5h 35m
Mon 10/1211:10 am -
Nonstop1h 15m
Deal found 9/4![Southwest logo]()
$270
This Southwest deal was found by Cheapflights users on 9/7. 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 9/302:10 pm -
2 stops6h 00m
Sat 10/35:00 pm -
1 stop3h 40m
Deal found 9/7![Southwest logo]()
$280
This Southwest deal was found by Cheapflights users on 9/5. 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 9/285:40 am -
2 stops6h 15m
Thu 10/154:50 pm -
1 stop7h 00m
Deal found 9/5![Southwest logo]()
$322
This Southwest deal was found by Cheapflights users on 9/5. 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.
Sun 9/205:35 pm -
Nonstop1h 10m
Fri 10/25:00 pm -
Nonstop1h 20m
Deal found 9/5![Southwest logo]()
$347
This Southwest deal was found by Cheapflights users on 9/4. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 12/255:45 am -
1 stop5h 25m
Fri 12/2512:40 pm -
2 stops7h 05m
Deal found 9/4![Southwest logo]()
$356
Last-minute flights from Ontario to San JoseDiscover last-minute flight deals from Ontario to San Jose. Data last updated September 8, 2026 and is based on user searches.
Discover last-minute flight deals from Ontario to San Jose. Data last updated September 8, 2026 and is based on user searches.
This Trip.com deal was found by Cheapflights users on 9/8. 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 Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 10/18:00 am -
1 stop4h 43m
Mon 10/51:38 pm -
1 stop19h 31m
Deal found 9/8![Frontier logo]()
$128
This Southwest deal was found by Cheapflights users on 9/8. 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 10/39:25 am -
1 stop6h 40m
Mon 10/56:45 am -
Nonstop1h 20m
Deal found 9/8![Southwest logo]()
$127
This Southwest deal was found by Cheapflights users on 9/8. 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 10/611:25 am -
Nonstop1h 10m
Thu 10/86:45 am -
Nonstop1h 20m
Deal found 9/8![Southwest logo]()
$117
This Southwest deal was found by Cheapflights users on 9/8. 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 10/66:10 am -
2 stops6h 30m
Tue 10/137:25 am -
Nonstop1h 15m
Deal found 9/8![Southwest logo]()
$132
This CheapOair deal was found by Cheapflights users on 9/8. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/72:30 pm -
1 stop22h 50m
Mon 10/129:02 pm -
1 stop13h 29m
Deal found 9/8![Frontier logo]()
$133
This Southwest deal was found by Cheapflights users on 9/4. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 10/93:55 pm -
Nonstop1h 10m
Sat 10/104:35 pm -
Nonstop1h 25m
Deal found 9/4![Southwest logo]()
$134
This Southwest deal was found by Cheapflights users on 9/8. 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 10/93:55 pm -
Nonstop1h 10m
Tue 10/136:00 pm -
1 stop3h 25m
Deal found 9/8![Southwest logo]()
$154
This Booking.com deal was found by Cheapflights users on 9/8. 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.
Thu 10/158:35 pm -
1 stop16h 45m
Mon 10/199:02 pm -
1 stop19h 28m
Deal found 9/8![Frontier logo]()
$130
This Southwest deal was found by Cheapflights users on 9/4. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 10/245:30 am -
2 stops6h 40m
Tue 10/278:05 am -
2 stops7h 30m
Deal found 9/4![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 September 8, 2026.
Search for one-way flight options from Ontario to San Jose. Find affordable one-way fares based on user searches. Data last updated September 8, 2026.
This Frontier deal was found by Cheapflights users on 9/3. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 10/18:00 am -
1 stop4h 43m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/3![Frontier logo]()
$59
This Super.com deal was found by Cheapflights users on 9/8. 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.
Wed 9/302:30 pm -
1 stop22h 13m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/8![Frontier logo]()
$64
This Booking.com deal was found by Cheapflights users on 9/8. 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.
Thu 10/158:35 pm -
1 stop16h 45m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/8![Frontier logo]()
$65
This Trip.com deal was found by Cheapflights users on 9/8. 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 Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 11/128:35 pm -
1 stop17h 11m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/8![Frontier logo]()
$67
This Southwest deal was found by Cheapflights users on 9/8. 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 10/74:15 pm -
1 stop5h 15m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/8![Southwest logo]()
$69
This Southwest deal was found by Cheapflights users on 9/3. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 10/35:45 am -
1 stop6h 50m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/3![Southwest logo]()
$74
This Super.com deal was found by Cheapflights users on 9/8. 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.
Fri 10/98:00 am -
1 stop5h 20m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/8![Frontier logo]()
$75
This Frontier deal was found by Cheapflights users on 9/8. 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 12/108:32 pm -
1 stop10h 12m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/8![Frontier logo]()
$82
This FlightHub deal was found by Cheapflights users on 9/8. 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 11/198:35 pm -
1 stop18h 55m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/8![Frontier logo]()
$85
This Southwest deal was found by Cheapflights users on 9/7. 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 10/27:05 pm -
Nonstop1h 10m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/7![Southwest logo]()
$86
This CheapOair deal was found by Cheapflights users on 9/8. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 12/210:32 pm -
1 stop8h 12m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/8![Frontier logo]()
$87
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 September 8, 2026.
Most accurate provider | FlightHub 3 stars |
|---|---|
Most trusted provider | FlightHub 3 stars |
Round-trip from | $117 (Southwest) |
One-way from | $59 (Frontier) |
Popular in | May |
Cheapest in | October |
Average price | $265 |
Good round-trip deal | $238 or less |
Good one-way deal | $152 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 7,457,451 searches. Data last updated September 8, 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
OntarioSan Jose
ONT Ontario - SJC San Jose
ONTSJC
Ontario
Fri 12/4
5:55 pm-10:53 am
1 stop16h 58m
San Jose
Wed 12/31
12:00 am-12:00 am
Nonstop0h 00m
$127
OntarioSan Jose
ONT Ontario - SJC San Jose
ONTSJC
Ontario
Fri 11/6
4:09 pm-9:43 am
1 stop17h 34m
San Jose
Wed 12/31
12:00 am-12:00 am
Nonstop0h 00m
$127
OntarioSan Jose
ONT Ontario - SJC San Jose
ONTSJC
Ontario
Sat 11/7
6:00 pm-10:50 am
1 stop16h 50m
San Jose
Wed 12/31
12:00 am-12:00 am
Nonstop0h 00m
$127
OntarioSan Jose
ONT Ontario - SJC San Jose
ONTSJC
Ontario
Fri 11/6
4:00 pm-10:20 pm
2 stops6h 20m
San Jose
Wed 12/31
12:00 am-12:00 am
Nonstop0h 00m
$143
OntarioSan Jose
ONT Ontario - SJC San Jose
ONTSJC
Ontario
Thu 11/5
5:00 am-11:35 am
2 stops6h 35m
San Jose
Wed 12/31
12:00 am-12:00 am
Nonstop0h 00m
$143
OntarioSan Jose
ONT Ontario - SJC San Jose
ONTSJC
Ontario
Thu 10/22
5:20 am-12:20 pm
2 stops7h 00m
San Jose
Wed 12/31
12:00 am-12:00 am
Nonstop0h 00m
$143
OntarioSan Jose
ONT Ontario - SJC San Jose
ONTSJC
Ontario
Fri 10/30
6:02 am-1:18 pm
1 stop7h 16m
San Jose
Wed 12/31
12:00 am-12:00 am
Nonstop0h 00m
$152
OntarioSan Jose
ONT Ontario - SJC San Jose
ONTSJC
Ontario
Fri 11/6
8:35 am-2:15 pm
1 stop5h 40m
San Jose
Mon 11/9
6:30 am-7:45 am
Nonstop1h 15m
$154
OntarioSan Jose
ONT Ontario - SJC San Jose
ONTSJC
Ontario
Wed 2/24
10:03 am-7:54 pm
2 stops9h 51m
San Jose
Wed 12/31
12:00 am-12:00 am
Nonstop0h 00m
$167
OntarioSan Jose
ONT Ontario - SJC San Jose
ONTSJC
Ontario
Wed 3/3
10:03 am-5:56 pm
2 stops7h 53m
San Jose
Wed 12/31
12:00 am-12:00 am
Nonstop0h 00m
$202
Showing 1-10 of 23 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 September.
| 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 60 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, October 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 September 8, 2026.
It’s optimal to fly from Ontario to San Jose, California in the afternoon. By choosing this option you can save up to 10% on the cost of your flight, compared to a flight at noon.
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 September 5, 2026.
Travelers seeking maximum savings on their Ontario to San Jose, California flight should consider departing on Monday 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 September 8, 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.
Comfort
8.0
Food
7.0
Overall
8.0
Crew
8.6
Boarding
8.1
Entertainment
7.5
Reviews
1 / 20
8.0
ExcellentWalter,Aug 2025
OAK - SAN
Comfort
8.0
Food
7.0
Overall
8.0
Crew
8.6
Boarding
8.1
Entertainment
7.5
Reviews
1 / 20
8.0
ExcellentWalter,Aug 2025
OAK - SAN
Comfort
8.0
Food
7.0
Overall
8.0
Crew
8.6
Boarding
8.1
Entertainment
7.5
Reviews
1 / 20
8.0
ExcellentWalter,Aug 2025
OAK - SAN
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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$145 | Average$350 | FlexibilityNo cancel fee | On-time63% |