How long is the flight from Ontario to USA?

Departing from Ontario to USA will take you 1h. The distance from Ontario to USA is about 197 mi. Generally, flights for this route are nonstop.

What are the cheapest airlines to fly from Ontario to USA one-way?

$29 is the cheapest one-way deal found within the past few days, from Frontier. You may also be able to find cheap deals on Southwest and United Airlines, with prices starting from $59 and $69, respectively.

In terms of precipitation, rainfall in USA ranges from 2.8 - 4.5 inches per month. July is typically the wettest month, when rainfall can reach 4.5 in. February is typically the driest time to visit USA when rainfall is around 2.8 in.

If weather is an important factor for your trip to USA, use this chart to help with planning. For those seeking warmer temperatures, July is the ideal time of year to visit, when temperatures reach an average of 77.0 F. Travelers looking to avoid the cold should look outside of January, when temperatures are typically at their lowest (around 33.8 F).

What are the most popular routes from Ontario to USA?

While some choose either Ontario - Dallas/Fort Worth or Ontario - San Francisco, Ontario - Seattle/Tacoma Intl is the most popular route from Ontario to USA.

What are the most popular airlines that fly from Ontario to USA?

Frontier, American Airlines and Southwest are the most popular airlines when flying from Ontario to USA.

What airport do you fly from for flights from Ontario to United States?

Ontario (ONT) is the airport you will fly out of if you book a flight from Ontario to United States. It is only a 3.1 mi journey to Ontario (ONT) from Ontario’s city center.

Can I find deals for flights from Ontario to USA that include hotel bookings?

Yes. In addition to deals on Ontario to USA flights, Cheapflights offers vacation packages that include both flights and hotel.

How can I find direct flights from Ontario to USA?

After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from Ontario to USA.

Can I find deals for business class flights from Ontario to USA?

Yes. Cheapflights offers flight deals from Ontario to USA by cabin class. In addition to browsing deals, you can also filter by cabin class on the search results page after making a search.

$29+ Cheap Flights from Ontario to the United States

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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

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.

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Cheap flight deals from Ontario to USA

Most accurate provider	CheapOair 3 stars
Most trusted provider	CheapOair 3 stars
Round-trip from	$57 (Kiwi.com)
One-way from	$29 (Priceline)
Popular in	December
Cheapest in	January
Average price	$365
Good round-trip deal	$114 or less
Good one-way deal	$80 or less

Provider with most accurate pricing for Los Angeles-New York (NYC) flight deals.

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Provider most trusted by Cheapflights users for Los Angeles-New York (NYC) flights.

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From Ontario to USA

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One-way flight from Ontario to USA

Search Deals

Highest demand for flights based on searches. 4% potential increase in price ($16 potential increase over avg. RT price).

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Cheapest flight prices on average. 2% potential price decrease ($7 potential savings vs. average RT price).

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Average for round-trip flights in October 2025

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Price to beat on a round-trip flight from Ontario to USA.

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Price to beat on a one-way flight from Ontario to USA.

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Find flight deals from Ontario to USA

Cheapest flights from Ontario to USA
Explore the most affordable flight options available from Ontario to USA. Find the lowest fares from popular airlines and budget airlines, with prices last updated on October 28, 2025.

Sun 12/146:15 amONT - LAS

Nonstop1h 07mFrontier

Wed 12/178:13 pmLAS - ONT

Nonstop1h 04mFrontier

Deal found 10/28

$54

Tue 12/96:15 amONT - LAS

Nonstop1h 07mFrontier

Wed 12/178:13 pmLAS - ONT

Nonstop1h 04mFrontier

Deal found 10/28

$57

Wed 12/106:15 amONT - LAS

Nonstop1h 07mFrontier

Thu 12/118:13 pmLAS - ONT

Nonstop1h 04mFrontier

Deal found 10/26

$58

Sun 12/146:15 amONT - LAS

Nonstop1h 07mFrontier

Wed 1/77:05 pmLAS - ONT

Nonstop1h 08mFrontier

Deal found 10/27

$59

Sat 12/136:15 amONT - LAS

Nonstop1h 07mFrontier

Thu 12/184:13 pmLAS - ONT

Nonstop1h 09mFrontier

Deal found 10/28

$60

Sat 12/66:15 amONT - LAS

Nonstop1h 07mFrontier

Sat 12/68:13 pmLAS - ONT

Nonstop1h 04mFrontier

Deal found 10/27

$62

Sun 12/216:00 amONT - LAS

Nonstop1h 07mFrontier

Thu 12/258:13 pmLAS - ONT

Nonstop1h 04mFrontier

Deal found 10/28

$69

Tue 12/26:15 amONT - LAS

Nonstop1h 07mFrontier

Mon 12/88:13 pmLAS - ONT

Nonstop1h 04mFrontier

Deal found 10/28

$70

Tue 12/166:15 amONT - LAS

Nonstop1h 07mFrontier

Fri 12/194:01 pmLAS - ONT

Nonstop1h 08mFrontier

Deal found 10/28

$73

Sat 12/66:15 amONT - LAS

Nonstop1h 07mFrontier

Mon 12/88:13 pmLAS - ONT

Nonstop1h 04mFrontier

Deal found 10/26

$74

Fri 12/510:12 pmONT - SFO

Nonstop1h 40mFrontier

Sun 12/710:03 pmSFO - ONT

Nonstop1h 28mFrontier

Deal found 10/26

$74

Sun 12/75:18 pmONT - LAS

Nonstop1h 09mFrontier

Thu 12/118:13 pmLAS - ONT

Nonstop1h 04mFrontier

Deal found 10/26

$75

Best flights from Ontario to USA
Discover carefully curated flight deals from Ontario to USA that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated October 28, 2025.

Sun 12/74:01 pmONT - DEN

Nonstop2h 21mFrontier

Sat 12/1312:58 pmDEN - ONT

Nonstop2h 27mFrontier

Deal found 10/26

$103

Thu 1/18:55 pmONT - LAS

Nonstop1h 00mSouthwest

Mon 1/57:20 amLAS - ONT

1 stop5h 15mSouthwest

Deal found 10/27

$144

Fri 11/141:40 pmONT - SFO

Nonstop1h 24mUnited Airlines

Sun 11/169:30 pmSFO - ONT

Nonstop1h 21mUnited Airlines

Deal found 10/26

$157

Sat 1/244:03 pmONT - DEN

1 stop6h 33mAlaska Airlines

Wed 1/287:00 amDEN - ONT

1 stop9h 08mAlaska Airlines

Deal found 10/26

$176

Fri 12/195:49 pmONT - SEA

Nonstop3h 00mDelta

Tue 1/1311:15 amSEA - ONT

Nonstop2h 41mDelta

Deal found 10/27

$187

Tue 11/188:45 amONT - PHX

1 stop7h 16mFrontier

Thu 11/207:00 amPHX - ONT

1 stop5h 11mFrontier

Deal found 10/25

$110

Wed 1/2112:57 pmONT - PHX

Nonstop1h 21mAmerican Airlines

Sat 1/243:48 pmPHX - ONT

Nonstop1h 17mAmerican Airlines

Deal found 10/28

$231

Mon 11/104:05 pmONT - PHX

1 stop7h 24mFrontier

Thu 11/1310:17 amPHX - ONT

1 stop3h 34mFrontier

Deal found 10/26

$110

Mon 12/226:45 amONT - DEN

Nonstop2h 21mFrontier

Mon 12/2910:32 pmDEN - ONT

Nonstop2h 27mFrontier

Deal found 10/28

$122

Sat 1/108:30 amONT - LAS

2 stops7h 30mSouthwest

Mon 1/1211:15 amLAS - ONT

1 stop4h 50mSouthwest

Deal found 10/28

$159

Wed 12/31:50 pmONT - SFO

Nonstop1h 24mUnited Airlines

Wed 12/319:10 pmSFO - ONT

Nonstop1h 23mUnited Airlines

Deal found 10/26

$173

Tue 12/912:13 pmONT - SEA

Nonstop2h 56mAlaska Airlines

Sat 12/138:43 amSEA - ONT

Nonstop2h 36mAlaska Airlines

Deal found 10/27

$177

Sat 12/65:49 pmONT - SEA

Nonstop3h 01mDelta

Sun 12/78:30 amSEA - ONT

Nonstop2h 43mDelta

Deal found 10/26

$189

Wed 12/106:00 amONT - SFO

Nonstop1h 24mUnited Airlines

Mon 12/159:28 pmSFO - ONT

Nonstop1h 21mUnited Airlines

Deal found 10/26

$173

Thu 12/46:15 amONT - PHX

1 stop11h 16mFrontier

Sun 12/77:00 amPHX - ONT

1 stop9h 06mFrontier

Deal found 10/26

$144

Sat 12/612:13 pmONT - SEA

Nonstop2h 56mAlaska Airlines

Sat 12/133:57 pmSEA - ONT

Nonstop2h 36mAlaska Airlines

Deal found 10/27

$177

Sat 12/612:50 pmONT - LAS

2 stops5h 15mSouthwest

Mon 12/85:10 pmLAS - ONT

Nonstop1h 05mSouthwest

Deal found 10/28

$179

Wed 11/126:38 pmONT - SFO

Nonstop1h 24mUnited Airlines

Fri 11/1411:15 amSFO - ONT

Nonstop1h 22mUnited Airlines

Deal found 10/27

$177

Sat 1/179:00 amONT - LAS

2 stops5h 45mSouthwest

Tue 1/201:25 pmLAS - ONT

1 stop3h 30mSouthwest

Deal found 10/27

$179

Thu 12/115:49 pmONT - SEA

Nonstop3h 00mDelta

Sun 12/142:19 pmSEA - ONT

Nonstop2h 48mDelta

Deal found 10/27

$197

Sun 11/96:45 amONT - PHX

1 stop16h 44mFrontier

Mon 11/109:17 amPHX - ONT

1 stop13h 40mFrontier

Deal found 10/27

$152

Sat 12/69:59 amONT - PHX

Nonstop1h 17mAmerican Airlines

Mon 12/89:45 pmPHX - ONT

Nonstop1h 15mAmerican Airlines

Deal found 10/26

$231

Wed 1/74:03 pmONT - DEN

1 stop6h 33mAlaska Airlines

Sun 1/1111:49 amDEN - ONT

1 stop6h 16mAlaska Airlines

Deal found 10/26

$191

Wed 11/126:00 amONT - SFO

Nonstop1h 24mUnited Airlines

Thu 11/134:13 pmSFO - ONT

Nonstop1h 21mUnited Airlines

Deal found 10/27

$179

Fri 1/910:40 amONT - LAS

Nonstop1h 05mSouthwest

Sun 1/112:25 pmLAS - ONT

2 stops5h 35mSouthwest

Deal found 10/26

$189

Wed 1/214:03 pmONT - DEN

1 stop6h 33mAlaska Airlines

Sun 1/2511:49 amDEN - ONT

1 stop6h 16mAlaska Airlines

Deal found 10/27

$191

Wed 12/31:29 pmONT - DFW

1 stop6h 35mDelta

Thu 12/115:19 amDFW - ONT

1 stop7h 43mDelta

Deal found 10/28

$217

Wed 12/101:50 pmONT - SFO

Nonstop1h 24mUnited Airlines

Sat 12/139:28 pmSFO - ONT

Nonstop1h 21mUnited Airlines

Deal found 10/26

$192

Wed 12/243:10 pmONT - LAS

Nonstop1h 05mSouthwest

Sun 12/287:55 pmLAS - ONT

1 stop3h 15mSouthwest

Deal found 10/28

$194

Thu 12/256:00 amONT - SEA

Nonstop2h 57mAlaska Airlines

Wed 12/319:35 pmSEA - ONT

Nonstop2h 39mAlaska Airlines

Deal found 10/26

$197

Last-minute flights from Ontario to USA
Discover last-minute flight deals from Ontario to USA. Data last updated October 28, 2025 and is based on user searches.

Mon 11/310:42 pmONT - SFO

Nonstop1h 29mFrontier

Thu 11/1310:11 pmSFO - ONT

Nonstop1h 29mFrontier

Deal found 10/26

$75

Mon 11/310:42 pmONT - SFO

Nonstop1h 29mFrontier

Mon 11/1010:21 pmSFO - ONT

Nonstop1h 29mFrontier

Deal found 10/27

$79

Thu 11/610:42 pmONT - SFO

Nonstop1h 29mFrontier

Fri 11/1410:21 pmSFO - ONT

Nonstop1h 29mFrontier

Deal found 10/25

$74

Thu 11/610:42 pmONT - SFO

Nonstop1h 29mFrontier

Mon 11/1010:21 pmSFO - ONT

Nonstop1h 29mFrontier

Deal found 10/28

$78

Mon 11/1010:42 pmONT - SFO

Nonstop1h 29mFrontier

Fri 11/1410:21 pmSFO - ONT

Nonstop1h 29mFrontier

Deal found 10/26

$80

Mon 11/1010:42 pmONT - SFO

Nonstop1h 29mFrontier

Thu 11/135:45 amSFO - ONT

1 stop7h 06mFrontier

Deal found 10/27

$87

Mon 11/1010:42 pmONT - SFO

Nonstop1h 29mFrontier

Sat 11/156:34 amSFO - ONT

1 stop17h 16mFrontier

Deal found 10/27

$89

Thu 11/137:44 pmONT - LAS

Nonstop1h 11mFrontier

Fri 11/147:46 pmLAS - ONT

1 stop4h 04mFrontier

Deal found 10/28

$82

Thu 11/1310:05 amONT - SFO

1 stop7h 44mFrontier

Mon 11/1710:21 pmSFO - ONT

Nonstop1h 29mFrontier

Deal found 10/27

$82

Fri 11/1410:42 pmONT - SFO

Nonstop1h 29mFrontier

Tue 11/188:02 amSFO - ONT

1 stop13h 25mFrontier

Deal found 10/26

$83

Wed 11/266:30 amONT - LAS

Nonstop1h 10mFrontier

Wed 12/38:13 pmLAS - ONT

Nonstop1h 04mFrontier

Deal found 10/28

$88

Thu 11/273:31 pmONT - LAS

Nonstop1h 13mFrontier

Thu 12/48:13 pmLAS - ONT

Nonstop1h 04mFrontier

Deal found 10/28

$90

One-way flights from Ontario to USA
Search for one-way flight options from Ontario to USA. Find affordable one-way fares based on user searches. Data last updated October 28, 2025.

Thu 12/116:15 amONT - LAS

Nonstop1h 07mFrontier

Deal found 10/26

$29

Mon 12/226:00 pmONT - LAS

Nonstop1h 11mFrontier

Deal found 10/25

$31

Sat 12/136:15 amONT - LAS

Nonstop1h 07mFrontier

Deal found 10/26

$32

Sat 12/66:00 amONT - SFO

Nonstop1h 24mUnited Airlines

Deal found 10/28

$39

Mon 12/2210:12 pmONT - SFO

Nonstop1h 40mFrontier

Deal found 10/26

$40

Tue 12/306:00 amONT - LAS

Nonstop1h 07mFrontier

Deal found 10/26

$45

Mon 11/1010:42 pmONT - SFO

Nonstop1h 29mFrontier

Deal found 10/27

$45

Mon 11/176:00 amONT - LAS

Nonstop1h 11mFrontier

Deal found 10/27

$46

Wed 11/198:00 amONT - LAS

Nonstop1h 12mFrontier

Deal found 10/27

$47

Sun 12/216:00 amONT - LAS

Nonstop1h 07mFrontier

Deal found 10/27

$48

Thu 11/610:42 pmONT - SFO

Nonstop1h 29mFrontier

Deal found 10/27

$48

Sun 11/235:06 pmONT - LAS

Nonstop1h 09mFrontier

Deal found 10/26

$49

Fly from

Fly to

Route

Depart

Return

Price

OntarioDenver

ONT - DEN

ONTDEN

Ontario

Sun 12/7

4:01 pm-7:22 pm

Nonstop2h 21m

Denver Intl

Sat 12/13

12:58 pm-2:25 pm

Nonstop2h 27m

$103

OntarioPhoenix

ONT - PHX

ONTPHX

Ontario

Tue 11/18

8:45 am-5:01 pm

1 stop7h 16m

Phoenix Sky Harbor Intl

Thu 11/20

7:00 am-11:11 am

1 stop5h 11m

$110

OntarioPhoenix

ONT - PHX

ONTPHX

Ontario

Mon 11/10

4:05 pm-12:29 am

1 stop7h 24m

Phoenix Sky Harbor Intl

Thu 11/13

10:17 am-12:51 pm

1 stop3h 34m

$110

OntarioDenver

ONT - DEN

ONTDEN

Ontario

Mon 12/22

6:45 am-10:06 am

Nonstop2h 21m

Denver Intl

Mon 12/29

10:32 pm-11:59 pm

Nonstop2h 27m

$122

OntarioLas Vegas

ONT - LAS

ONTLAS

Ontario

Thu 1/1

8:55 pm-9:55 pm

Nonstop1h 00m

Las Vegas Harry Reid Intl

Mon 1/5

7:20 am-12:35 pm

1 stop5h 15m

$144

OntarioPhoenix

ONT - PHX

ONTPHX

Ontario

Thu 12/4

6:15 am-6:31 pm

1 stop11h 16m

Phoenix Sky Harbor Intl

Sun 12/7

7:00 am-3:06 pm

1 stop9h 06m

$144

OntarioPhoenix

ONT - PHX

ONTPHX

Ontario

Sun 11/9

6:45 am-12:29 am

1 stop16h 44m

Phoenix Sky Harbor Intl

Mon 11/10

9:17 am-9:57 pm

1 stop13h 40m

$152

OntarioSan Francisco

ONT - SFO

ONTSFO

Ontario

Fri 11/14

1:40 pm-3:04 pm

Nonstop1h 24m

San Francisco

Sun 11/16

9:30 pm-10:51 pm

Nonstop1h 21m

$157

OntarioLas Vegas

ONT - LAS

ONTLAS

Ontario

Sat 1/10

8:30 am-4:00 pm

2 stops7h 30m

Las Vegas Harry Reid Intl

Mon 1/12

11:15 am-4:05 pm

1 stop4h 50m

$159

OntarioSan Francisco

ONT - SFO

ONTSFO

Ontario

Wed 12/3

1:50 pm-3:14 pm

Nonstop1h 24m

San Francisco

Wed 12/31

9:10 pm-10:33 pm

Nonstop1h 23m

$173

Flights are sorted by cheapest round-trip flights first.

Deals found on 10/27

Showing 1-10 of 60 results

...

Best time to book a flight from Ontario to USA

Have a flexible travel schedule? Discover the best time to fly to USA from Ontario 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 Ontario to the United States

What is the cheapest month to book a flight from Ontario to USA?

Currently, December is the cheapest month in which you can book a flight from Ontario to USA (average of $17). Flying from Ontario to USA in July is currently the most expensive (average of $49). 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 US?

A simple way to save on the total cost of your ticket is to fly from Ontario to USA in the afternoon. If you’re flexible enough to do this you can expect to save up to 31% on your trip compared to booking a flight in the morning.

What is the cheapest day to fly from Ontario to USA?

Travelers seeking maximum savings on their Ontario to USA flight should consider departing on Sunday at noon when fares are most often at their lowest. Wednesday afternoons flights should be avoided if possible as fares are typically the most expensive at this time.

Reviews of airlines servicing USA

Read reviews from past customers who have flown Southwest, Delta, and United Airlines from Ontario to the United States. Users can see the overall rating for each airline as well as how each is rated in terms of entertainment options, comfort, food, crew/service, and boarding process.

Southwest

8.0

Very good

4,240 reviews

Reviews

1 / 20

8.0

Excellent

Walter,Aug 2025

OAK - SAN

Dozens of flights and I've never seen a row's beverages forgotten. I even went back and asked the attendant to check on them and nothing. I really hope it didn't have something to do with the Black mother with her kid in the row. Otherwise it was a typical Southwest flight, rapid boarding, tolerable leg room.

Southwest

8.0

Very good

4,240 reviews

Southwest

8.0

Very good

4,240 reviews

Reviews

1 / 20

8.0

Excellent

Walter,Aug 2025

OAK - SAN

Delta

7.9

Good

7,994 reviews

Southwest

8.0

Very good

4,240 reviews

Reviews

1 / 20

8.0

Excellent

Walter,Aug 2025

OAK - SAN

United Airlines

7.4

Good

9,001 reviews

Southwest

8.0

Very good

4,240 reviews

Reviews

1 / 20

8.0

Excellent

Walter,Aug 2025

OAK - SAN

American Airlines

7.2

Good

11,032 reviews

Southwest

8.0

Very good

4,240 reviews

Reviews

1 / 20

8.0

Excellent

Walter,Aug 2025

OAK - SAN

Frontier

5.8

Fair

3,124 reviews

Southwest

8.0

Very good

4,240 reviews

Reviews

1 / 20

8.0

Excellent

Walter,Aug 2025

OAK - SAN

Related info for your journey

What airport do you fly from for flights from Ontario to United States?
Ontario (ONT) is the airport you will fly out of if you book a flight from Ontario to United States. It is only a 3.1 mi journey to Ontario (ONT) from Ontario’s city center.
How long is the flight from Ontario to USA?
Departing from Ontario to USA will take you 1h. The distance from Ontario to USA is about 197 mi. Generally, flights for this route are nonstop.
What are the cheapest airlines to fly from Ontario to USA one-way?
$29 is the cheapest one-way deal found within the past few days, from Frontier. You may also be able to find cheap deals on Southwest and United Airlines, with prices starting from $59 and $69, respectively.
What are the most popular routes from Ontario to USA?
While some choose either Ontario - Dallas/Fort Worth or Ontario - San Francisco, Ontario - Seattle/Tacoma Intl is the most popular route from Ontario to USA.
Can I find deals for flights from Ontario to USA that include hotel bookings?
Yes. In addition to deals on Ontario to USA flights, Cheapflights offers vacation packages that include both flights and hotel.
How can I find direct flights from Ontario to USA?
After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from Ontario to USA.
Can I find deals for business class flights from Ontario to USA?
Yes. Cheapflights offers flight deals from Ontario to USA by cabin class. In addition to browsing deals, you can also filter by cabin class on the search results page after making a search.
What is the cheapest month to book a flight from Ontario to USA?
Currently, December is the cheapest month in which you can book a flight from Ontario to USA (average of $17). Flying from Ontario to USA in July is currently the most expensive (average of $49). 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.

See more FAQs

Browse thousands of different options on Cheapflights for your next trip

Top 8 airlines flying from Ontario to USA

Airline	Cheapest	Average	Flexibility	On-time
Spirit Airlines	Cheapest$24	Average$168	FlexibilityNo cancel fee	On-time65%
Frontier	Cheapest$36	Average$178	FlexibilityNo cancel fee	On-time62%
United Airlines	Cheapest$58	Average$386	FlexibilityNo cancel fee	On-time69%
Alaska Airlines	Cheapest$67	Average$371	FlexibilityNo cancel fee	On-time75%
Southwest	Cheapest$97	Average$378	FlexibilityNo cancel fee	On-time63%
Delta	Cheapest$147	Average$364	FlexibilityNo cancel fee	On-timeN/A
JetBlue	Cheapest$237	Average$330	FlexibilityNo cancel fee	On-time62%
American Airlines	Cheapest$242	Average$431	FlexibilityNo cancel fee	On-time71%

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$29+ Cheap flights from Ontario (ONT) to the United States

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 1/7. Fares are subject to change and may not be available on all flights or dates of travel.

Find cheap flights from Ontario to USA with Cheapflights

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Cheap flight deals from Ontario to USA

Keep the following information in mind while searching for Ontario to USA flight deals. Data was last updated October 28, 2025.

Most accurate provider

Most trusted provider

Round-trip from

One-way from

Popular in

Cheapest in

Average price

Good round-trip deal

Good one-way deal

Find flight deals from Ontario to USA

Cheapest flights from Ontario to USAExplore the most affordable flight options available from Ontario to USA. Find the lowest fares from popular airlines and budget airlines, with prices last updated on October 28, 2025.

Explore the most affordable flight options available from Ontario to USA. Find the lowest fares from popular airlines and budget airlines, with prices last updated on October 28, 2025.

Cheapflights Fare Finder

Use the filters below to find and compare flights from Ontario to the United States that are best for you.

Best time to book a flight from Ontario to USA

Have a flexible travel schedule? Discover the best time to fly to USA from Ontario with our price prediction graph.

Cheapflights Insights

Everything you need to know about your flight from Ontario to the United States

What is the cheapest month to book a flight from Ontario to USA?

What is the cheapest time of day to fly from ONT to US?

Find hourly flight availability from Ontario to USA. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated October 28, 2025.

What is the cheapest day to fly from Ontario to USA?

Use this chart to determine the cheapest time to fly round-trip from Ontario to USA. Price data was last updated on October 26, 2025.

Reviews of airlines servicing USA

Get insights into the airlines that provide service to USA. 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 USA. Reviews last updated October 28, 2025.

Read reviews from past customers who have flown Southwest, Delta, and United Airlines from Ontario to the United States. Users can see the overall rating for each airline as well as how each is rated in terms of entertainment options, comfort, food, crew/service, and boarding process.

Related info for your journey

Find useful and relevant information for your journey from Ontario to USA. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.

What airport do you fly from for flights from Ontario to United States?

How long is the flight from Ontario to USA?

What are the cheapest airlines to fly from Ontario to USA one-way?

What are the most popular routes from Ontario to USA?

Can I find deals for flights from Ontario to USA that include hotel bookings?

How can I find direct flights from Ontario to USA?

Can I find deals for business class flights from Ontario to USA?

What is the cheapest month to book a flight from Ontario to USA?

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Cheapest flights from Ontario to USA
Explore the most affordable flight options available from Ontario to USA. Find the lowest fares from popular airlines and budget airlines, with prices last updated on October 28, 2025.