What is the cheapest airline that flies from Ontario to United States?

Frontier, Alaska Airlines, and United Airlines are the most popular carriers operating from Ontario to United States

What is the most punctual flight time for Ontario to the United States flights?

Generally, flights departing in the morning tend to experience fewer delays. Flights in the evening have, in the past, seen delays more frequently in comparison.

What airlines fly to United States?

Frontier, Spirit Airlines and United Airlines are the top three most popular airlines that fly to United States from Ontario according to our data. Frontier is the first choice among our users, with 37% of people opting to fly with this airline when traveling to United States. Keep in mind that there are 12 different airlines that fly to United States on a routine basis, so you have a few additional options to choose from.

How often are flights from Ontario to the United States delayed?

Historically, on average around 12% of flights between Ontario and United States have experienced a delay on any given week. The average delay length over the past 12 months has been 126 minutes.

What day of the week experiences the fewest flight delays on this route?

Saturday is statistically the day of the week which experiences the fewest number of delays on this flight route. Thursday has historically seen more delays on average compared to the rest of the week.

How many flights depart from Ontario to United States on average per day?

As of December 2025, there are 35 flights per day flying from Ontario to United States. The most common time of day flights depart is 7:00AM, with 38% of flights taking off at noon.

How many flights depart from Ontario to United States on average per week?

As of December 2025, there are 246 flights per week flying from Ontario to United States. The most common day of the week flights depart is Wed, with 20% of flights taking off on this day.

Which airline has the best punctuality record on Ontario to the United States flights?

According to our data, Delta have had the least number of delays on this route over the last 12 months; with about 4% of their flights experiencing any sort of delay.

When did momondo last update prices for flights from Ontario Airport to United States?

Prices for flights from Ontario Airport to United States refresh daily.

How many operators does momondo search for flights from Ontario Airport to United States?

As of December 2025, there are 9 operators available to choose from for flights from Ontario Airport to United States.

How old do you have to be to fly from Ontario Airport to United States?

The minimum age for a child to fly alone is five, but airlines that offer an unaccompanied minor (UNMR) service may have their own age limitations. Flight duration, scheduling, and layovers are among the considerations that may influence age limits. We recommend that you double-check with the airline you are booking with for travel from Ontario Airport to United States.

What documentation or ID do you need to fly to United States?

The necessary travel and health documents for your United States trip may vary depending on your travel plans and individual circumstances. Generally, you should have various documents, such as a national ID card or driver's license and a passport that is valid for six months beyond your scheduled arrival date. We recommend seeking advice from your airline or a trusted third party, such as IATA.

$37 Cheap Flights from Ontario to the United States in 2025/26

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Cheap round-trip flights

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8:30 am - 9:36 amONT-LAS

1h 06mnonstop

11:32 am - 12:42 pmLAS-ONT

1h 10mnonstop

$53Frontier

Find Deal

Tue, Feb 10 - Tue, Feb 17

3:07 pm - 4:19 pmONT-LAS

1h 12mnonstop

12:21 pm - 1:32 pmLAS-ONT

1h 11mnonstop

$54Frontier

Find Deal

Tue, Jan 20 - Fri, Jan 23

4:04 pm - 5:11 pmONT-LAS

1h 07mnonstop

8:45 am - 9:50 amLAS-ONT

1h 05mnonstop

$58Frontier

Find Deal

Tue, Jan 6 - Wed, Jan 7

7:30 am - 10:34 amONT-SEA

3h 04mnonstop

5:30 am - 12:17 pmSEA-ONT

6h 47m1 stop

$129Delta

Find Deal

Thu, Mar 5 - Thu, Mar 12

5:25 pm - 11:25 pmONT-SEA

6h 00m1 stop

7:55 am - 12:15 pmSEA-ONT

4h 20m1 stop

$131Southwest

Find Deal

Fri, Feb 27 - Mon, Mar 2

5:50 am - 11:05 amONT-SEA

5h 15m1 stop

1:20 pm - 9:05 pmSEA-ONT

7h 45m1 stop

$136Southwest

Find Deal

Sat, Jan 17 - Sun, Jan 18

7:19 pm - 10:10 pmONT-SEA

2h 51mnonstop

6:00 pm - 8:36 pmSEA-ONT

2h 36mnonstop

$137Alaska Airlines

Find Deal

Tue, Jan 6 - Sat, Jan 10

11:53 am - 2:44 pmONT-SEA

2h 51mnonstop

9:20 pm - 11:56 pmSEA-ONT

2h 36mnonstop

$138Alaska Airlines

Find Deal

Fri, Jan 9 - Sun, Jan 11

7:16 am - 4:12 pmONT-HOU

6h 56m1 stop

6:00 am - 10:08 amHOU-ONT

6h 08m1 stop

$159American Airlines

Find Deal

Sat, Jan 10 - Sat, Jan 17

3:09 pm - 10:46 pmONT-HOU

5h 37m1 stop

10:35 am - 4:05 pmHOU-ONT

7h 30m2 stops

$164American Airlines

Find Deal

Sat, Jan 10 - Sat, Jan 17

Frontier flights from Ontario to United States

Our best Frontier deals on Ontario to United States flight tickets

Frontier

Feb 10

ONT8:30 amOntario

1h 06m

LAS9:36 amLas Vegas Harry Reid Intl

Feb 17

LAS11:32 amLas Vegas Harry Reid Intl

1h 10m

ONT12:42 pmOntario

$53

Find similar

Frontier

Jan 20

ONT3:07 pmOntario

1h 12m

LAS4:19 pmLas Vegas Harry Reid Intl

Jan 23

LAS12:21 pmLas Vegas Harry Reid Intl

1h 11m

ONT1:32 pmOntario

$54

Find similar

Frontier

Jan 6

ONT4:04 pmOntario

1h 07m

LAS5:11 pmLas Vegas Harry Reid Intl

Jan 7

LAS8:45 amLas Vegas Harry Reid Intl

1h 05m

ONT9:50 amOntario

$58

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United Airlines flights from Ontario to United States

Our best United Airlines deals on Ontario to United States flight tickets

United Airlines

Dec 16

ONT1:50 pmOntario

1h 24m

SFO3:14 pmSan Francisco

Dec 16

SFO4:16 pmSan Francisco

1h 21m

ONT5:37 pmOntario

$132

Find similar

United Airlines

Dec 14

ONT1:34 pmOntario

6h 41m

1 stop

EWR11:15 pmNewark

Jan 14

EWR3:30 pmNewark

9h 28m

1 stop

ONT9:58 pmOntario

$352

Find similar

United Airlines

Dec 11

ONT5:05 amOntario

9h 17m

1 stop

LGA5:22 pmNew York LaGuardia

Dec 16

LGA2:15 pmNew York LaGuardia

11h 34m

2 stops

ONT10:49 pmOntario

$360

Find similar

Fly from

Fly to

Route

Depart

Return

Price

OntarioLas Vegas

ONT - LAS

ONTLAS

Ontario

Tue 2/10

8:30 am-9:36 am

Nonstop1h 06m

Las Vegas Harry Reid Intl

Tue 2/17

11:32 am-12:42 pm

Nonstop1h 10m

$53

OntarioLas Vegas

ONT - LAS

ONTLAS

Ontario

Tue 1/20

3:07 pm-4:19 pm

Nonstop1h 12m

Las Vegas Harry Reid Intl

Fri 1/23

12:21 pm-1:32 pm

Nonstop1h 11m

$54

OntarioLas Vegas

ONT - LAS

ONTLAS

Ontario

Tue 1/6

4:04 pm-5:11 pm

Nonstop1h 07m

Las Vegas Harry Reid Intl

Wed 1/7

8:45 am-9:50 am

Nonstop1h 05m

$58

OntarioSeattle

ONT - SEA

ONTSEA

Ontario

Thu 3/5

7:30 am-10:34 am

Nonstop3h 04m

Seattle/Tacoma Intl

Thu 3/12

5:30 am-12:17 pm

1 stop6h 47m

$129

OntarioSeattle

ONT - SEA

ONTSEA

Ontario

Fri 2/27

5:25 pm-11:25 pm

1 stop6h 00m

Seattle/Tacoma Intl

Mon 3/2

7:55 am-12:15 pm

1 stop4h 20m

$131

OntarioSeattle

ONT - SEA

ONTSEA

Ontario

Sat 1/17

5:50 am-11:05 am

1 stop5h 15m

Seattle/Tacoma Intl

Sun 1/18

1:20 pm-9:05 pm

1 stop7h 45m

$136

OntarioSeattle

ONT - SEA

ONTSEA

Ontario

Tue 1/6

7:19 pm-10:10 pm

Nonstop2h 51m

Seattle/Tacoma Intl

Sat 1/10

6:00 pm-8:36 pm

Nonstop2h 36m

$137

OntarioSeattle

ONT - SEA

ONTSEA

Ontario

Fri 1/9

11:53 am-2:44 pm

Nonstop2h 51m

Seattle/Tacoma Intl

Sun 1/11

9:20 pm-11:56 pm

Nonstop2h 36m

$138

OntarioHouston

ONT - HOU

ONTHOU

Ontario

Sat 1/10

7:16 am-4:12 pm

1 stop6h 56m

Houston Hobby

Sat 1/17

6:00 am-10:08 am

1 stop6h 08m

$159

OntarioHouston

ONT - HOU

ONTHOU

Ontario

Sat 1/10

3:09 pm-10:46 pm

1 stop5h 37m

Houston Hobby

Sat 1/17

10:35 am-4:05 pm

2 stops7h 30m

$164

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How to get the cheapest flight ticket from Ontario to United States

Look no further. We've gone through all the searches for this route on momondo so you have the important information and insights to find the cheapest flight ticket for your trip

Prices

Airlines

Delays

Other information

What is the cheapest month to fly to United States?

In general, January is the cheapest month to fly from Ontario to United States. Due to it being the ‘off-season’ during this time, you can expect flight prices to be around $256. If you aren’t able to travel during the month of January, then book flights to United States from Ontario during February instead. Flights to United States in February, while not as cheap as those in January, still average around $312.

What is the cheapest day to depart on your flight to United States?

According to our data, Saturday is the cheapest day to fly to United States from Ontario. The lowest ticket price found for a Saturday departure recently was $335. Keep in mind that prices can always vary depending on your route and whether or not you are flying domestic or international. If your travel schedule is flexible, try to avoid departing on a Wednesday because tickets tend to average around $387. These prices are subject to change though, so be sure to set up a Price Alert for flights to United States.

What is the cheapest time of day to depart on your flight to United States?

The cheapest time of day to fly to United States is in the afternoon when flights can be purchased for as low as $309. Try not to purchase tickets in the evening because they tend to be around $359. Of course, these prices can vary depending on the time of year and what airport you fly to.

What is the cheapest Ontario to United States flight route?

Fly from Ontario to San Francisco for the best Ontario - United States flight prices

How far in advance should I book a flight to United States?

You are more likely to see cheaper flights to United States from Ontario when booking weeks ahead of your departure date. In general, you can expect to find flights to United States for around $349 when searching weeks out. However, flight prices might be lower outside of this timeframe. For example, people recently found flights to United States from Ontario for as low as $274 on momondo.

What cabin class options are available on Ontario to United States flights?

There are 4 cabin classes available to choose from on Ontario to United States flights. Cabin price and availability will vary by airline so perform a search above to find the right deals for you.

Can stopping save me money on Ontario to United States flights?

No. A direct flight is the cheapest option for a flight between Ontario to United States.

Cheap Ontario to United States flight deals and tips

Find info about flight duration, direct flights, and airports for your flight from Ontario to United States

Best Price Found	$87
Direct flights	Every day
Airports in United States	1 airport

The best one-way flight to United States from Ontario in the past 72 hours is $87. The best round-trip flight deal from Ontario to United States found on momondo in the last 72 hours is $135.

Direct flights go from Ontario to United States every day.

There is 1 airport near United States: Las Vegas Harry Reid Intl (LAS)

Search flight deals

When did momondo last update prices for flights from Ontario Airport to United States?
Prices for flights from Ontario Airport to United States refresh daily.
How many operators does momondo search for flights from Ontario Airport to United States?
As of December 2025, there are 9 operators available to choose from for flights from Ontario Airport to United States.
How old do you have to be to fly from Ontario Airport to United States?
The minimum age for a child to fly alone is five, but airlines that offer an unaccompanied minor (UNMR) service may have their own age limitations. Flight duration, scheduling, and layovers are among the considerations that may influence age limits. We recommend that you double-check with the airline you are booking with for travel from Ontario Airport to United States.
What documentation or ID do you need to fly to United States?
The necessary travel and health documents for your United States trip may vary depending on your travel plans and individual circumstances. Generally, you should have various documents, such as a national ID card or driver's license and a passport that is valid for six months beyond your scheduled arrival date. We recommend seeking advice from your airline or a trusted third party, such as IATA.
What is the most popular plane model from Ontario to United States?
Based on momondo bookings for flights between Ontario and United States, the leading plane model is Airbus A320neo, making up 13.58% of the total bookings. Other popular models include Boeing 737 MAX 8 with 11.77%, Airbus A321neo with 9.47%, and Boeing 737-800 Passenger/BBJ2 (winglets) with 9.35%.

Best airlines flying from Ontario to United States

Compare and see reviews for airlines that fly from Ontario to United States with momondo

Airline	Rating	Free Cancellation	Price
Spirit Airlines	PriceFrom $24	Free Cancellation	Rating 6.3 8,157 reviews	Search Spirit Airlines flights
Frontier	PriceFrom $35	Free Cancellation	Rating 5.8 3,092 reviews	Search Frontier flights
United Airlines	PriceFrom $59	Free Cancellation	Rating 7.4 9,064 reviews	Search United Airlines flights
Alaska Airlines	PriceFrom $67	Free Cancellation	Rating 8.0 11,392 reviews	Search Alaska Airlines flights
Southwest	PriceFrom $97	Free Cancellation	Rating 8.0 4,254 reviews	Search Southwest flights
Delta	PriceFrom $178	Free Cancellation	Rating 7.9 8,008 reviews	Search Delta flights
JetBlue	PriceFrom $223	Free Cancellation	Rating 7.2 2,900 reviews	Search JetBlue flights
American Airlines	PriceFrom $242	Free Cancellation	Rating 7.2 11,045 reviews	Search American Airlines flights

Why use momondo?

Why should I use momondo to find a flight deal from Ontario to United States?

We help find the flight that best suits your needs, momondo compares prices from hundreds of airlines and travel agents and helps you filter them to find the best flight from Ontario to United States for you.

Can I find flights from Ontario to United States with flexible booking policies on momondo?

Yes. All flights to United States from Ontario on momondo can be compared and filtered by various policies on offer, including flexible booking.

How can momondo help me find flights from Ontario to United States?

Once you have performed a search in the form on the page, momondo provides useful filters and insights. We can show you the cheapest days and times to fly as well as help filter your options to help you make an informed choice when booking flights to United States from Ontario.

I’m not ready to book a flight from Ontario to United States right now. Can momondo alert me if prices change?

If you are simply researching potential flights to United States, momondo offers a useful price alert feature which will track prices for flights to United States from Ontario and alert you when they change.

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Popular cities in the United States

Flights to New Yorkfrom $39

Flights to Los Angelesfrom $48

Flights to Miamifrom $47

Flights to Chicagofrom $44

Flights to Orlandofrom $41

Flights to San Franciscofrom $49

Flights to Las Vegasfrom $40

Flights to Washington, D.C.from $41

Flights to Bostonfrom $56

Flights to Atlantafrom $37

Flights to Dallasfrom $53

Flights to Seattlefrom $59

Cheap flights from Ontario to the United States from $37

This is the cheapest one-way flight price found by a momondo user in the last 72 hours by searching for a flight from Ontario to the United States departing on 3/11. Fares may change, and may not be available for all flights or travel dates. Click the price to refresh the search for this deal.

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Frontier flights from Ontario to United States

Our best Frontier deals on Ontario to United States flight tickets

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Our best United Airlines deals on Ontario to United States flight tickets

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

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How to get the cheapest flight ticket from Ontario to United States

Look no further. We've gone through all the searches for this route on momondo so you have the important information and insights to find the cheapest flight ticket for your trip

What is the cheapest month to fly to United States?

What is the cheapest day to depart on your flight to United States?

What is the cheapest time of day to depart on your flight to United States?

The cheapest time of day to fly to United States is in the afternoon when flights can be purchased for as low as $309. Try not to purchase tickets in the evening because they tend to be around $359. Of course, these prices can vary depending on the time of year and what airport you fly to.

What is the cheapest Ontario to United States flight route?

Fly from Ontario to San Francisco for the best Ontario - United States flight prices

How far in advance should I book a flight to United States?

What cabin class options are available on Ontario to United States flights?

There are 4 cabin classes available to choose from on Ontario to United States flights. Cabin price and availability will vary by airline so perform a search above to find the right deals for you.

Can stopping save me money on Ontario to United States flights?

No. A direct flight is the cheapest option for a flight between Ontario to United States.

What is the cheapest airline that flies from Ontario to United States?

Frontier, Alaska Airlines, and United Airlines are the most popular carriers operating from Ontario to United States

What airlines fly to United States?

How often are flights from Ontario to the United States delayed?

Historically, on average around 12% of flights between Ontario and United States have experienced a delay on any given week. The average delay length over the past 12 months has been 126 minutes.

What is the most punctual flight time for Ontario to the United States flights?

Generally, flights departing in the morning tend to experience fewer delays. Flights in the evening have, in the past, seen delays more frequently in comparison.

What day of the week experiences the fewest flight delays on this route?

Saturday is statistically the day of the week which experiences the fewest number of delays on this flight route. Thursday has historically seen more delays on average compared to the rest of the week.

Which airline has the best punctuality record on Ontario to the United States flights?

According to our data, Delta have had the least number of delays on this route over the last 12 months; with about 4% of their flights experiencing any sort of delay.

How many flights depart from Ontario to United States on average per day?

As of December 2025, there are 35 flights per day flying from Ontario to United States. The most common time of day flights depart is 7:00AM, with 38% of flights taking off at noon.

How many flights depart from Ontario to United States on average per week?

As of December 2025, there are 246 flights per week flying from Ontario to United States. The most common day of the week flights depart is Wed, with 20% of flights taking off on this day.

Cheap Ontario to United States flight deals and tips

Find info about flight duration, direct flights, and airports for your flight from Ontario to United States

Best Price Found

Direct flights

Airports in United States

When did momondo last update prices for flights from Ontario Airport to United States?

How many operators does momondo search for flights from Ontario Airport to United States?

How old do you have to be to fly from Ontario Airport to United States?

What documentation or ID do you need to fly to United States?

What is the most popular plane model from Ontario to United States?

Best airlines flying from Ontario to United States

Compare and see reviews for airlines that fly from Ontario to United States with momondo

Why use momondo?

Why should I use momondo to find a flight deal from Ontario to United States?

Can I find flights from Ontario to United States with flexible booking policies on momondo?

How can momondo help me find flights from Ontario to United States?

I’m not ready to book a flight from Ontario to United States right now. Can momondo alert me if prices change?

An easier way to manage your United States trip

We make it super easy to schedule, organize and travel with friends or family. Trips is free — and available to use no matter where you book.

Get notified when prices go down

Daily price changes in your inbox - only with Price Alerts.

Find better results for your trip to the United States

Popular cities in the United States

Popular flights according to clicks in the last 7 days on momondo