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Find cheap flights from Ontario to the United States from $37

This is the cheapest one-way flight price found by a KAYAK user in the last 72 hours by searching for a flight from Ontario to the United States departing on 8/8. Fares are subject to change and may not be available on all flights or dates of travel. Click the price to replicate the search for this deal.
1 adult
0 bags
Wed 7/10
Wed 7/17

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Best United States Flight Deals

Cheapest round-trip prices found by our users on KAYAK in the last 72 hours

New York
New York1 stop$155
Las Vegas
Las Vegasnonstop$33
Miami
Miami1 stop$156
San Francisco
San Franciscononstop$38
Chicago
Chicago1 stop$136
Boston
Boston1 stop$248
Denver
Denvernonstop$48
Seattle
Seattlenonstop$50
Fort Lauderdale
Fort Lauderdale1 stop$260
Atlanta
Atlanta1 stop$155
Dallas
Dallasnonstop$74
Tampa
Tampa1 stop$176
Houston
Houston1 stop$107
Honolulu
Honolulunonstop$289
San Diego
San Diego1 stop$342
Philadelphia
Philadelphia1 stop$154

Good to know

Low season

January

High season

June

Cheapest flight

$37
Best time to beat the crowds with an average 10% drop in price.
Most popular time to fly with an average 17% increase in price.
Flight from Ontario to Las Vegas

FAQs - booking United States flights

  • How does KAYAK find such low prices on flights from Ontario to the United States?

    KAYAK is a travel search engine. That means we look across the web to find the best prices we can find for our users. With over 2 billion flight queries processed yearly, we are able to display a variety of prices and options on flights from Ontario to the United States.

  • How does KAYAK's flight Price Forecast tool help me choose the right time to buy my flight ticket from Ontario to the United States?

    KAYAK’s flight Price Forecast tool uses historical data to determine whether the price for a flight to the United States from Ontario is likely to change within 7 days, so travelers know whether to wait or book now.

  • What is the Hacker Fare option on flights from Ontario to the United States?

    Hacker Fares allow you to combine one-way tickets in order to save you money over a traditional round-trip ticket. You could then fly to the United States with an airline and back to Ontario with another airline.

  • What is KAYAK's "flexible dates" feature and why should I care when looking for a flight from Ontario to the United States?

    Sometimes travel dates aren't set in stone. If your preferred travel dates have some wiggle room, flexible dates will show you all the options when flying to the United States from Ontario up to 3 days before/after your preferred dates. You can then pick the flights that suit you best.

See more FAQs

Top tips for finding cheap flights to the United States

  • Looking for a cheap flight? 25% of our users found tickets from Ontario to the following destinations at these prices or less: Denver $95 one-way - $162 round-trip; Dallas $151 one-way - $339 round-trip; Seattle $91 one-way - $128 round-trip
  • Morning departure is around 7% cheaper than an evening flight, on average*.
*Average of the lowest prices shown in KAYAK’s search results for departures within the next 30 days

Top 5 airlines serving from Ontario to the United States

Need help choosing which airline to fly with from Ontario to the United States? KAYAK airline reviews give an overall score for each airline based on loads of factors, including comfort, boarding, in-flight entertainment and more, to make your decision easier. See airline scores according to verified KAYAK customer reviews.
8.0
Alaska AirlinesOverall score based on 9254 reviews
7.3Food
7.9Comfort
8.2Boarding
8.6Crew
7.3Entertainment
Airline reviews

Everything was great but there were no entertainment options available.

6.0 GoodKyndra Homuth, Jun 2024SFO - PDX
Read more about Alaska Airlines reviews

Everything was great but there were no entertainment options available.

Flight was delayed 2 hours. It was too cold inside the cabin. My seat mate had no jacket so she was shivering the entire flight. The stewardess says there’s no available blanket.

The plane had to sit on the tarmac for 45 minutes once it had landed. Not Alaska’s fault.

No prob with entertainment-would have selected n/a if it had been an option. No entertainment-flight was only a short hop. Great flight,

I love having assigned seats and being able to check bags at the gate, if needed. Both are super-helpful when traveling with a toddler!!!

It was really good and that's why we choose AA over other airlines.

Seats are uncomfortable but let room was adequate. The snack is pretty weak and the staff not particularly friendly.

Flight was cancelled just before we boarded. I had to stayed an extra night in SF and arrived one day late. Also I had to flight back JFK and not Newark since they didn't have flight to Newark until very late the following day. A real bad experience on this flight. It took me 2 days to get back home.

We landed in San Diego from Fresno 10 min late and our gate was occupied. We waited OVER AN HOUR to get to the gate and didnt get any updates about what was happening until I asked. Then we were told it would be another 5 minutes....which turned into 25. My wife was waiting in cell phone lot over an hour and finally had to leave. It cost me $40 cab ride and a fight with my wife. THanks for nothing Alaska Air.

The flight was delayed by more than two hours. A notification ahead of time would be most helpful.

There was plenty of overhead room but half of the passengers were told they had to check their carryon bags. My partner and I checked in as early as possible and our seats were split across the aisle.

Flew first class so everything was great. But maybe because the flights were red eye, no meals were served, just chips. I flew Alaska Air 1st class at 9PM (2 hour flight) and they served beef short rib sliders!

There was a loud squeaky sound the whole time we were flying.

I didn’t not like that I could not select my seat and ended up with the worse seat.

The landing was bad and the hostess came two times and i was sleeping but when she served the person that nexts to me I woke up and she didn’t even asked me if I need any drink or snacks two times!!!!

Plane was late because of a mechanical malfunction and the food listed as available was not. Flight attendants seem over worked and under paid. They just done seem happy. And that can be seen in their faces.

Waited 3 hours on a plane to de-ice due to manpower issues. Waited another hour and a half once we landed because of a gate issue. Missed my connections. Created. A total of 13 hours of delay.

Great, on time departure, friendly and accommodating crew, great leg room, Smith flight

Plane was turned around due to fog half way into the flight, Delta did not properly direct passengers to stay on same flight and instead failed to properly rebook on Alaska

Like most domestic flights in the US, you are basically on your own with this airline when it comes to food, so be sure to purchase meals and drinks ahead of time or expect to arrive starving and dehydrated (like I was).

Horrible, the flights kept delaying, so it is obvious that we won't be able to make it to the next connection. No easier/real agent on site to help you figure this out. UA agent on other counters refuse to assist you and direct us to use the QR code/call customer service. So inefficient and poor. While technology seems convenient, but it's not the best interest/experience for customers need help while there is active issue need assistance.

Flight was delayed due to the late arrival of the catering truck, which is quite unacceptable. There was a beverage service, but no pretzel, or cookie, or nuts were served in coach.

I had a great flight. Everything went smoothly and the flight arrived early.

On time take off…US cabins look tired and need of refresh!

I paid $380 for my one-way ticket from California to Minnesota. The fair did not include online check-in. I received instructions from their app to check in at a kiosk. At the kiosk, the boarding pass would not print until an actual person came to verify that I had a personal item and not a carry-on item, On the plane, the person next to me was drunk and allowed to continue to order alcohol. United is garbage I’d rather fly spirit.

Do not like the feeling of being in the basic economy. Everyone should feel good no matter what.

Terrible! The plane was old and you are required to connect your own device to their Wi-Fi rather than have entertainment options in the back of the seat in front of you. The Wi-Fi went out during the flight and there was only one plug for the devices every two seats. Three out of five surrounding my family did not work. The seats and spaces under them were so small I could not fit my backpack, which I’ve always brought on flights and fit before no problem. The crew were unpleasant and patronizing.

Due to one crew member not showing up to work, our flight was significantly delayed causing us to miss our connecting flight in Houston to Mississippi causing us to be delayed by more than 6 hours and missing our event all together. Very disappointing. All because ONE crew member called in sick. United did grant us a $15 meal voucher, which was a small but appreciated concession that I wasn’t able to use because I ordered my lunch and paid for it before applying the concession, and the staff said it was too late to use it. Ugh! We also had a TWO delay coming back from Mississippi, but that was on American Airlines and it was due to weather, so not their fault. Anyway, not at all impressed with United’s handling of our flight and the HUGE disappointment of missing our important family event for our 90 year old mother. All that money and all that stress and emotions for nothing. Having to wait the hour to bring an employee from LAX seemed like something that should not have happened. Why don’t you have a local back-up? Santa Ana is not a little airport in a rural area.

Crew was great and did their best to make us comfortable and captain came out at the beginning to announce why the flight was delayed, weather situation up ahead, and kept us updated throughout the flight.

United WiFi is consistently unusable (it can take 10 mins to load a single web page). If you need Wifi to do work, be prepared to lose half a day of productivity.

The flight was delayed several times without explanation. The seats were terribly uncomfortable and wifi isn’t included. All these make for a less than ideal flight.

Internet service was erratic. Crew service was poor and slow. My luggage on this non-stop flight was lost and not recovered

Flight was 1/2 hour delayed leaving Phoenix. Otherwise it was an average flight. Flight crew on this trip was very nice.

Horrible - they lied to me about baggage & boarding, even though I specifically spoke to their agents the day before my flight about my issue. When I showed up they did not let me board and stranded me at my airport until I bought a new flight with money I did not have to spend.

The experience was great and much better than the flight going out. of course I was in first class but the service was excellent

Comfort of seats, ease of boarding. Food selection could be better

Food options were limited which is absolutely embarrassing for a Flight of this size The staff did not come around as much and I am not accustomed to such poor service from American Airlines Drinks I believe were limited to soda and water

Crew were attentive and friendly. Flight was smooth and early! I enjoyed the less crowded plane. Thank you!

We are gluten free, there were not any available complimentary gluten free options.

No meal on a cross country flight? SFO-MiA is pretty much the definition of a coast to coast flight. No meal provided. Sky high wi-fi rates too. Stop nickel and diming your customers.

I strongly dislike Frontier. I find them barebones, the seats not particularly comfortable, the nickel and diming is maddening, the app is TERRIBLE - super confusing to navigate, and the last 4 frontier flights I have flown have been on AVERAGE 2 hours late, one ruining a fancy night out in Vegas with reservations made well in advance, which was nodded to with a measly 5000 miles, which translates to almost nothing. At least credit a free checked bag or something.

8 hr delay. had to buy another ticket with another airline

Four and a half hour delay in total. What frustrates me most is the poor communication and disorganization.

I appreciated the upgrade to free cary-on bag and seat selection at no charge

FRONTIER SUCKS! The agent downstairs tricked me into booking, just to get to the gate. At the gate, they told me they couldn't help. I then called Customer Service. They and the gate attendants kept blaming each other. Neither side was willing to help the customer.

The agent at check-in was strident, unwelcoming, and condescending to customers ahead of me.

Flight was delay 9hrs and nothing was provided at airport, had to go and get a room to sleep in, paid for Uber back and fort with no offers until we landed back home a 1hr later for a $75 voucher for a future flight.

Didn't like anything..entire crew was very rude to everyone on the flight. Plane old and the trays fall down on you the while time you're flying. Charged more for a carry on bag than for the plane ticket itself. Did make it from point a to point b, but worth the extra money to fly with another airline

9 hours of delay!! Was not able to check my luggage that I paid for!!!

It was delayed 9 hours for operational reasons, despite the plane arriving to the airport on time.

Book cheap flights from Ontario to the United States

Recent round-trip flight deals

8/7Wed
nonstopFrontier
1h 29mONT-LAS
8/13Tue
nonstopFrontier
1h 09mLAS-ONT
$38
8/20Tue
nonstopFrontier
1h 26mONT-SFO
8/28Wed
nonstopFrontier
1h 21mSFO-ONT
$38
7/9Tue
nonstopAlaska Airlines
2h 40mONT-SEA
7/16Tue
nonstopAlaska Airlines
2h 33mSEA-ONT
$157
8/13Tue
1 stopDelta
5h 13mONT-SEA
8/20Tue
1 stopDelta
4h 29mSEA-ONT
$176
7/25Thu
nonstopAlaska Airlines
2h 40mONT-SEA
7/31Wed
nonstopAlaska Airlines
2h 35mSEA-ONT
$177
8/6Tue
1 stopDelta
6h 59mONT-SEA
8/10Sat
1 stopDelta
6h 45mSEA-ONT
$196
8/28Wed
nonstopUnited Airlines
2h 18mONT-DEN
8/31Sat
nonstopUnited Airlines
2h 17mDEN-ONT
$197
9/21Sat
nonstopUnited Airlines
1h 27mONT-SFO
9/22Sun
nonstopUnited Airlines
1h 26mSFO-ONT
$212
8/6Tue
1 stopAmerican Airlines
7h 40mONT-HOU
8/8Thu
1 stopAmerican Airlines
6h 54mHOU-ONT
$216
9/10Tue
2 stopsAmerican Airlines
9h 18mONT-LGA
9/17Tue
1 stopAmerican Airlines
9h 16mLGA-ONT
$231

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Recent one-way flight deals

8/8Thu
nonstopFrontier
1h 22mONT-LAS
$37
9/1Sun
nonstopFrontier
1h 26mONT-SFO
$37
7/13Sat
nonstopAlaska Airlines
2h 35mONT-SEA
$85
8/10Sat
1 stopAmerican Airlines
5h 59mONT-LAS
$98
7/16Tue
1 stopDelta
4h 28mONT-DEN
$98
8/9Fri
nonstopAlaska Airlines
2h 40mONT-SEA
$99
7/16Tue
1 stopAmerican Airlines
7h 37mONT-HOU
$108
7/1Mon
1 stopDelta
6h 20mONT-DFW
$108
9/16Mon
nonstopUnited Airlines
2h 18mONT-DEN
$119
12/6Fri
nonstopUnited Airlines
1h 26mONT-SFO
$133

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Last minute flights from Ontario to the United States

Last minute flight, train and bus deals

6/11Tue
nonstopFrontier
1h 15mONT-LAS
6/17Mon
nonstopFrontier
1h 10mLAS-ONT
$78
6/12Wed
nonstopFrontier
1h 28mONT-SFO
6/20Thu
nonstopFrontier
1h 23mSFO-ONT
$78
6/15Sat
multi-stopAmerican Airlines
7h 10mONT-ORD
6/22Sat
multi-stopAmerican Airlines
6h 22mORD-ONT
$259
6/15Sat
multi-stopDelta
10h 18mONT-ORD
6/19Wed
multi-stopDelta
6h 22mORD-ONT
$279
6/12Wed
multi-stopAmerican Airlines
7h 33mONT-LGA
6/14Fri
multi-stopAmerican Airlines
9h 15mLGA-ONT
$286
6/11Tue
multi-stopDelta
9h 54mONT-JFK
6/15Sat
multi-stopDelta
9h 02mJFK-ONT
$286
6/13Thu
nonstopUnited Airlines
1h 25mONT-SFO
6/17Mon
nonstopUnited Airlines
1h 32mSFO-ONT
$349
6/12Wed
multi-stopUnited Airlines
8h 55mONT-ORD
6/19Wed
multi-stopUnited Airlines
7h 35mORD-ONT
$390
6/12Wed
multi-stopAlaska Airlines
10h 38mONT-HNL
6/16Sun
multi-stopAlaska Airlines
9h 55mHNL-ONT
$419
6/14Fri
nonstopAlaska Airlines
2h 37mONT-SEA
6/18Tue
nonstopAlaska Airlines
2h 38mSEA-ONT
$467

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Ontario - United States Flights

Departure:

Ontario (ONT)United States

Return flight deals:

United States - Ontario

Cabin classes:

$363
$153
$296
$37

Browse destinations:

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