What airlines fly to United States?

Frontier, Spirit Airlines and Delta 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 36% 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.

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

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

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

As of July 2025, there are 450 flights per week flying from Ontario to United States. The most common day of the week flights depart is Thu, with 18% of flights taking off on this day.

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

As of July 2025, there are 64 flights per day flying from Ontario to United States. The most common time of day flights depart is 1:00PM, with 33% of flights taking off at noon.

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 July 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.

$28 Cheap Flights from Ontario to the United States in 2025

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Find the cheapest flights from Ontario to the United States

Round-trip

One-way

Last minute

Direct

Cheap round-trip flights

6:00 am - 7:13 amONT-LAS

1h 13mnonstop

3:08 pm - 4:19 pmLAS-ONT

1h 11mnonstop

$37Frontier

Find Deal

lun., jul. 28 - jue., jul. 31

12:28 pm - 1:40 pmONT-LAS

1h 12mnonstop

6:30 am - 7:33 amLAS-ONT

1h 03mnonstop

$46Frontier

Find Deal

jue., ago. 21 - dom., ago. 24

6:39 pm - 8:06 pmONT-SFO

1h 27mnonstop

10:45 am - 12:14 pmSFO-ONT

1h 29mnonstop

$57United Airlines

Find Deal

mié., jul. 23 - mar., ago. 12

6:10 am - 7:37 amONT-SFO

1h 27mnonstop

10:45 am - 12:14 pmSFO-ONT

1h 29mnonstop

$112United Airlines

Find Deal

mar., jul. 29 - mar., jul. 29

7:10 pm - 12:05 amONT-SEA

4h 55m1 stop

6:15 am - 12:10 pmSEA-ONT

5h 55m1 stop

$114Southwest

Find Deal

mar., ago. 5 - mar., ago. 12

5:25 am - 10:15 amONT-SEA

4h 50m1 stop

3:50 pm - 9:00 pmSEA-ONT

5h 10m1 stop

$124Southwest

Find Deal

sáb., ago. 16 - mié., sep. 3

6:10 am - 11:13 amONT-DFW

3h 03mnonstop

9:05 am - 9:58 amDFW-ONT

2h 53mnonstop

$149American Airlines

Find Deal

sáb., ago. 30 - mar., sep. 2

6:10 am - 5:52 pmONT-LGA

8h 42m1 stop

7:30 am - 1:39 pmLGA-ONT

9h 09m1 stop

$173American Airlines

Find Deal

mar., ago. 5 - mar., ago. 12

10:00 pm - 8:15 amONT-LGA

7h 15m1 stop

1:59 pm - 7:11 pmLGA-ONT

8h 12m1 stop

$276Delta

Find Deal

lun., ago. 11 - mar., ago. 19

7:05 am - 7:35 pmONT-JFK

9h 30m1 stop

1:30 pm - 7:11 pmJFK-ONT

8h 41m1 stop

$276Delta

Find Deal

sáb., ago. 9 - lun., ago. 18

United Airlines flights from Ontario to United States

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

United Airlines

Jul 23

ONT6:39 pmOntario

1h 27m

SFO8:06 pmSan Francisco

Aug 12

SFO10:45 amSan Francisco

1h 29m

ONT12:14 pmOntario

$57

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United Airlines

Jul 17

ONT6:10 amOntario

1h 27m

SFO7:37 amSan Francisco

Jul 26

SFO9:25 pmSan Francisco

1h 27m

ONT10:52 pmOntario

$99

Find similar

United Airlines

Jul 29

ONT6:10 amOntario

1h 27m

SFO7:37 amSan Francisco

Jul 29

SFO10:45 amSan Francisco

1h 29m

ONT12:14 pmOntario

$112

Find similar

Frontier flights from Ontario to United States

Our best Frontier deals on Ontario to United States flight tickets

Frontier

Jul 28

ONT6:00 amOntario

1h 13m

LAS7:13 amLas Vegas Harry Reid Intl

Jul 31

LAS3:08 pmLas Vegas Harry Reid Intl

1h 11m

ONT4:19 pmOntario

$37

Find similar

Frontier

Aug 21

ONT12:28 pmOntario

1h 12m

LAS1:40 pmLas Vegas Harry Reid Intl

Aug 24

LAS6:30 amLas Vegas Harry Reid Intl

1h 03m

ONT7:33 amOntario

$46

Find similar

Frontier

Aug 13

ONT7:00 amOntario

1h 11m

LAS8:11 amLas Vegas Harry Reid Intl

Aug 16

LAS8:45 pmLas Vegas Harry Reid Intl

1h 07m

ONT9:52 pmOntario

$47

Find similar

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

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 $277. If you aren’t able to travel during the month of January, then book flights to United States from Ontario during September instead. Flights to United States in September, while not as cheap as those in January, still average around $284.

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

According to our data, Monday is the cheapest day to fly to United States from Ontario. The lowest ticket price found for a Monday departure recently was $332. 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 Thursday because tickets tend to average around $374. 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 $356. 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 $359 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 $260 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	$28
Fastest flight time	1h 05m
Direct flights	Every day
Airports in United States	5 airports

The best one-way flight to United States from Ontario in the past 72 hours is $28. The best round-trip flight deal from Ontario to United States found on momondo in the last 72 hours is $37.

The fastest flight from Ontario to United States takes 1h 05m

Direct flights go from Ontario to United States every day.

There are 5 airports near United States: Dallas/Fort Worth (DFW), Denver Intl (DEN), San Francisco (SFO), Seattle/Tacoma Intl (SEA), Las Vegas Harry Reid Intl (LAS)

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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 July 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 15.69% of the total bookings. Other popular models include Airbus A321neo with 12.46%, Boeing 737-800 Passenger/BBJ2 (winglets) with 9.85%, and Boeing 737 MAX 8 with 9.67%.

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 $22	Free Cancellation	Rating 6.3 8,055 reviews	Search Spirit Airlines flights
Frontier	PriceFrom $35	Free Cancellation	Rating 5.9 3,271 reviews	Search Frontier flights
United Airlines	PriceFrom $58	Free Cancellation	Rating 7.4 8,846 reviews	Search United Airlines flights
Alaska Airlines	PriceFrom $67	Free Cancellation	Rating 8.0 10,000 reviews	Search Alaska Airlines flights
Delta	PriceFrom $85	Free Cancellation	Rating 8.0 7,952 reviews	Search Delta flights
Southwest	PriceFrom $98	Free Cancellation	Rating 8.0 4,250 reviews	Search Southwest flights
JetBlue	PriceFrom $207	Free Cancellation	Rating 7.3 2,910 reviews	Search JetBlue flights
American Airlines	PriceFrom $244	Free Cancellation	Rating 7.2 10,000 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 $37

Flights to Los Angelesfrom $39

Flights to Miamifrom $38

Flights to Chicagofrom $58

Flights to Las Vegasfrom $16

Flights to Orlandofrom $36

Flights to San Franciscofrom $56

Flights to Washington, D.C.from $38

Flights to Bostonfrom $57

Flights to Dallasfrom $66

Flights to Atlantafrom $49

Flights to Seattlefrom $82

Cheap flights from Ontario to the United States from $28

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 7/24. Fares may change, and may not be available for all flights or travel dates. Click the price to refresh the search for this deal.

Big names and deals

Big names and deals

Filter for what you want

Filter for what you want

Trusted and free

Trusted and free

Price Alerts

Price Alerts

Find the cheapest flights from Ontario to the United States

Cheap round-trip flights

Cheap one-way flights

Cheap last minute flights

Cheap direct flights

United Airlines flights from Ontario to United States

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

Frontier flights from Ontario to United States

Our best Frontier deals on Ontario to United States flight tickets

See travel insights to the United States from

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 $356. 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, United Airlines, and Southwest are the most popular carriers operating from Ontario to United States

What airlines fly to United States?

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

As of July 2025, there are 64 flights per day flying from Ontario to United States. The most common time of day flights depart is 1:00PM, with 33% of flights taking off at noon.

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

As of July 2025, there are 450 flights per week flying from Ontario to United States. The most common day of the week flights depart is Thu, with 18% 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

Fastest flight time

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