Find cheap United Airlines flights to Ontario
CMH — ONT
Aug 26 — Sep 21
Round-trip
1 adult, Economy
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Cheapest United Airlines flights from USA to OntarioExplore the most affordable United Airlines flight options available from USA to Ontario. Find the lowest fares with prices last updated on July 27, 2026.
Explore the most affordable United Airlines flight options available from USA to Ontario. Find the lowest fares with prices last updated on July 27, 2026.
This United Airlines 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 8/1710:37 am
SFO
- ONT
Nonstop1h 35m
United Airlines
Thu 8/206:08 am
ONT
- SFO
Nonstop1h 27m
United Airlines
Deal found 7/27![United Airlines logo]()
$117
This United Airlines deal was found by Cheapflights users on 7/23. 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.
Sat 8/1510:37 am
SFO
- ONT
Nonstop1h 35m
United Airlines
Wed 8/191:56 pm
ONT
- SFO
Nonstop1h 29m
United Airlines
Deal found 7/23![United Airlines logo]()
$137
This United Airlines 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 8/2210:37 am
SFO
- ONT
Nonstop1h 35m
United Airlines
Wed 8/261:56 pm
ONT
- SFO
Nonstop1h 29m
United Airlines
Deal found 7/27![United Airlines logo]()
$187
Best United Airlines flights from USA to OntarioDiscover carefully curated United Airlines flight deals from USA to Ontario that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated July 27, 2026.
Discover carefully curated United Airlines flight deals from USA to Ontario that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated July 27, 2026.
This United Airlines 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 11/76:50 pm
SFO
- ONT
Nonstop1h 25m
United Airlines
Thu 11/121:35 pm
ONT
- SFO
Nonstop1h 30m
United Airlines
Deal found 7/26![United Airlines logo]()
$187
This United Airlines 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 9/110:37 am
SFO
- ONT
Nonstop1h 35m
United Airlines
Tue 9/156:08 am
ONT
- SFO
Nonstop1h 27m
United Airlines
Deal found 7/25![United Airlines logo]()
$187
This United Airlines deal was found by Cheapflights users on 7/24. 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.
Thu 9/247:00 pm
SFO
- ONT
Nonstop1h 31m
United Airlines
Tue 10/61:52 pm
ONT
- SFO
Nonstop1h 29m
United Airlines
Deal found 7/24![United Airlines logo]()
$187
Direct United Airlines flights from USA to OntarioExplore non-stop United Airlines flight options from USA to Ontario based on user searches, and compare prices and availability for your desired travel dates. Data last updated July 27, 2026.
Explore non-stop United Airlines flight options from USA to Ontario based on user searches, and compare prices and availability for your desired travel dates. Data last updated July 27, 2026.
This United Airlines 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 8/1710:37 am
SFO
- ONT
Nonstop1h 35m
United Airlines
Thu 8/206:08 am
ONT
- SFO
Nonstop1h 27m
United Airlines
Deal found 7/27![United Airlines logo]()
$117
This United Airlines 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/219:25 pm
SFO
- ONT
Nonstop1h 26m
United Airlines
Thu 10/226:07 am
ONT
- SFO
Nonstop1h 27m
United Airlines
Deal found 7/26![United Airlines logo]()
$133
This United Airlines deal was found by Cheapflights users on 7/23. 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.
Sat 8/1510:37 am
SFO
- ONT
Nonstop1h 35m
United Airlines
Wed 8/191:56 pm
ONT
- SFO
Nonstop1h 29m
United Airlines
Deal found 7/23![United Airlines logo]()
$137
Last-minute United Airlines flights from USA to OntarioDiscover last-minute United Airlines flight deals from USA to Ontario. Data last updated July 27, 2026 and is based on user searches.
Discover last-minute United Airlines flight deals from USA to Ontario. Data last updated July 27, 2026 and is based on user searches.
This United Airlines 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 8/1710:37 am
SFO
- ONT
Nonstop1h 35m
United Airlines
Thu 8/206:08 am
ONT
- SFO
Nonstop1h 27m
United Airlines
Deal found 7/27![United Airlines logo]()
$117
This United Airlines deal was found by Cheapflights users on 7/23. 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.
Sat 8/1510:37 am
SFO
- ONT
Nonstop1h 35m
United Airlines
Wed 8/191:56 pm
ONT
- SFO
Nonstop1h 29m
United Airlines
Deal found 7/23![United Airlines logo]()
$137
This United Airlines 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 8/2210:37 am
SFO
- ONT
Nonstop1h 35m
United Airlines
Wed 8/261:56 pm
ONT
- SFO
Nonstop1h 29m
United Airlines
Deal found 7/27![United Airlines logo]()
$187
One-way United Airlines flights to OntarioSearch for one-way United Airlines flight options to Ontario. Find affordable one-way fares based on user searches. Data last updated July 27, 2026.
Search for one-way United Airlines flight options to Ontario. Find affordable one-way fares based on user searches. Data last updated July 27, 2026.
This United Airlines 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 8/1510:37 am
SFO
- ONT
Nonstop1h 35m
United Airlines
Deal found 7/25![United Airlines logo]()
$59
This United Airlines 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 12/2510:50 am
SFO
- ONT
Nonstop1h 25m
United Airlines
Deal found 7/26![United Airlines logo]()
$79
This United Airlines deal was found by Cheapflights users on 7/24. 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.
Sat 1/237:05 pm
DEN
- ONT
Nonstop2h 15m
United Airlines
Deal found 7/24![United Airlines logo]()
$79
Flights to Ontario with United Airlines at a glance
Find detailed information about United Airlines flights from USA to Ontario. Explore the options provided by United Airlines to plan your journey from USA to Ontario. Data last updated July 27, 2026.
Cheapflights Insights
Find cheap United Airlines flights to Ontario
US0-ONT
SFO-ONT
DEN-ONT
How long is the flight to Ontario with United Airlines?
On average, United Airlines flights from the United States to Ontario take 3 hours 20 minutes. Flights to Ontario from other popular cities in the United States will vary in length. Below are a few examples of popular routes and their flight times.
United Airlines weekly flight availability to Ontario
The most flights to Ontario operated by United Airlines are scheduled on a Monday (7 on average). You will have fewer flight options on Monday, which is when the least amount of flights are scheduled (7 on average).
When is the best time to book a flight to Ontario with United Airlines?
The best time to book a flight to Ontario with United Airlines is 67 days before departure. On average, fares are higher if you book 86 days before departure.
When is the cheapest time to fly to Ontario with United Airlines?
Users looking for the cheapest United Airlines fares to Ontario should consider flying on Wednesday at noon, when prices are typically cheapest. Budget-minded travellers will want to avoid Sunday mornings, when prices are usually at their highest.
FAQs about flights to Ontario with United Airlines
Reviews of United Airlines
See what Cheapflights users have to say about their United Airlines experience.
Overview
Reviews
United Airlines
10,000 reviews
Overview
Crew
8.1
Food
6.6
Comfort
7.3
Boarding
7.7
Entertainment
7.1
Recent reviews
8.0
|Jul 2026The crew was polite and professional.
8.0
|Jul 2026Getting to the gate on landing was slow
6.0
|Jun 2026It should not be delayed by 2 hours. I missed the important event due to this
8.0
|Jun 2026It was as expected
10.0
|Jun 2026Overall good
1 out of 3334
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