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Find cheap flights from Ontario to the United States from $39

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 6/14. 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
dc. 7/3
dc. 7/10

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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$184
Las Vegas
Las Vegasnonstop$53
Miami
Miami1 stop$182
San Francisco
San Franciscononstop$58
Chicago
Chicago1 stop$137
Boston
Boston1 stop$248
Washington, D.C.
Baltimore1 stop$182
Denver
Denvernonstop$56
Seattle
Seattlenonstop$98
Fort Lauderdale
Fort Lauderdale1 stop$260
Atlanta
Atlanta1 stop$176
Dallas
Dallasnonstop$98
Tampa
Tampa1 stop$180
Houston
Houstonnonstop$118
Honolulu
Honolulunonstop$239
San Diego
San Diego1 stop$372
Philadelphia
Philadelphia1 stop$180

Good to know

Low season

January

High season

June

Cheapest flight

$39
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 $93 one-way - $162 round-trip; Dallas $148 one-way - $335 round-trip; Seattle $94 one-way - $127 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 9197 reviews
7.3Entertainment
8.2Boarding
7.3Food
7.9Comfort
8.6Crew
Airline reviews

The flight was delayed for 2 hours and the last delay was not communicated and had to check manually.

2.0 MediocreAnonymous, Jun 2024SJC - LAX
Read more about Alaska Airlines reviews

The flight was delayed for 2 hours and the last delay was not communicated and had to check manually.

Loved the airport. The announcements for boarding were too loud & echoing in the large waiting area, so hard to follow. Other than that, we had a great experience.

First time traveling with them and they were great leaving on time arriving on time very clean planes 😊

Staff was very friendly. Flight was on time and arrived early. Flight was comfortable.

I didn’t know that food needed to be ordered ahead. Please include this in the reservation information. Overall, very good experience.

Plane hit turbulence diverted to Houston. We'll probably get in after 3am

Given incorrect gate upon check-in, corrected by the gate attendant, D6 rather than D5, minor inconvenience. As with the previous flight, passengers were admonished to voluntarily gate-check carry-on luggage with the statement that those in the last boarding group would have no choice but to do so. If the Boeing 737 MAX8/MAX9 doesn't have room for carry-ons it's an interior design flaw on the part of Boeing. Posting an advance warning would be helpful, such as "Boeing 737 MAX planes feature limited carry-on space. Please be aware." SFO's amenities and TSA much better than MCO's. Crew was amazing! Brought my own food because Alaska's onboard selection has soy in everything. Beverage service was excellent. This was the first and last trip with Alaska after the previous flight's issues. It's no reflection on the crew of this flight. They were great.

I had a middle seat in between two large men. It was a redeye so needless to say I didn’t get a minute of sleep. One guy was pouring over into my seat the other kept falling onto my shoulder

Great price on internet. I love that WiFi was so affordable. Got a lot done.

Ground staff at LAX was very helpful. The Alaska lounge food and service is better than most airport lounges. I think the Staff are well trained polite and actually seem happy to work there. Great service Thanks 🙏 Jjk

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).

You need to be a hacker to get the (Free) WiFi

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.

Awful. I got stuck next to a person carrying a dog and behind someone with a dog. People need to board these dogs downstairs. The cabin is crowded enough with your pets

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.

The staff was unprofessional and didn’t communicate very well. The boarding process was very disheveled, potentially due to a power outage the previous day but there was no contingency plan to properly get passengers boarded the following day. Once boarded the aircraft stayed on the tarmac for over 45 minutes due to high winds. The communication was sporadic but an announcement was finally made an additional 30 minutes later that the flight was cancelled but we couldn’t get off the plane. Prior to deplaning one of the gate agents came on the plane and made an announcement for everyone to pickup their checked bags and take a card to rebook a new reservation because they didn’t have adequate staff. Flights were missed, passengers went to different airports and there was little to no assistance from AA.

Apart from the delay due to unforeseen circumstances. The leg from sjc to dfw was fine. It was the leg from dfw to orf that we encountered issues mainly due to the flight attendant crew not being friendly. We had two small children and we needed some assistance to warm up milk so the baby would sleep. The crew just didn’t get it and made things very difficult. One made a remark that the baby’s dirty diaper smell was a “gift” to the plane in a rude way. Normally I’d brush that off as a funny comment if the rest of the trip the attendants were helpful or understanding of the difficulty we faced. But that wasn’t the case. We were met with rudeness on the second leg. Whereas on the first leg the crew were so nice and helpful.

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.

I am very disappointed with Frontier Airlines. They cancelled our flight because they couldn't find a crew member, and then didn't get us to our connecting flight. We had to cancel our whole vacation. We were promised flight and hotel vouchers, but they never sent them.

9hrs delay and didn’t provided anything until after flight landed $75 voucher for fiuture travel no meals or anything.

It was ridiculously hard to check in for the flight, and Frontier charged us a LOT of money to have a carry on suitcase, and then told everyone we could not carry on bags and had to check them through at the gate, and didn't refund the extra money we paid to have the suitcase as carry on.

I had a terrible experience with Frontier. I arrived before the 60 minute cut off and was told that Frontier has a two hour window for bags. I was then told the next available flight wasn’t until the end of the day (I had booked a 6am flight). I took a look around and saw other people being told that they could not board their flights or that they had to pay additional fees. I opted to rebook on American Airlines. There’s absolutely no straightforward way to contact Frontier, so this ticket was a complete waste of money. Oh - and the kicker is that the lady lied about the two hour cut off.

Our flight was delayed an hour, then when we got to board our flight finally, we were waiting in our seats for take off for 45 minutes before it was communicated that there was a maintenance issue therefore we waited on the plane for over an hour while that was resolved. We did not get to Phoenix until almost 3 hours after we were originally supposed to. This was the first and last time I will be flying Frontier.

There were 3 leg for the trip and each leg was delayed by 90 minutes or more. The boarding process takes forever with people waiting on the jetway even though most folks do not have carry-on. The whole process is poorly managed.

Book cheap flights from Ontario to the United States

Recent round-trip flight deals

8/24ds.
nonstopFrontier
1h 21mONT-LAS
8/24ds.
nonstopFrontier
1h 06mLAS-ONT
$53
10/2dc.
nonstopFrontier
1h 13mONT-LAS
10/2dc.
nonstopFrontier
1h 09mLAS-ONT
$55
7/9dt.
nonstopAlaska Airlines
2h 35mONT-SEA
7/9dt.
nonstopAlaska Airlines
2h 33mSEA-ONT
$151
8/9dv.
nonstopDelta
2h 47mONT-SEA
8/13dt.
nonstopDelta
2h 47mSEA-ONT
$177
11/9ds.
nonstopUnited Airlines
1h 26mONT-SFO
11/10dg.
nonstopUnited Airlines
1h 28mSFO-ONT
$179
7/17dc.
1 stopAlaska Airlines
5h 32mONT-SEA
7/23dt.
nonstopAlaska Airlines
2h 35mSEA-ONT
$186
8/7dc.
1 stopAmerican Airlines
5h 23mONT-LAS
8/9dv.
1 stopAmerican Airlines
4h 54mLAS-ONT
$196
7/2dt.
1 stopDelta
4h 26mONT-DEN
7/9dt.
1 stopDelta
6h 25mDEN-ONT
$196
7/2dt.
nonstopUnited Airlines
1h 20mONT-SFO
7/2dt.
nonstopUnited Airlines
1h 27mSFO-ONT
$197
8/5dl.
1 stopAmerican Airlines
5h 28mONT-DEN
8/13dt.
1 stopAmerican Airlines
5h 13mDEN-ONT
$217

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Recent one-way flight deals

6/14dv.
nonstopFrontier
1h 10mONT-LAS
$39
7/7dg.
nonstopFrontier
1h 26mONT-SFO
$39
8/31ds.
nonstopAmerican Airlines
3h 04mONT-DFW
$70
10/19ds.
1 stopAmerican Airlines
5h 48mONT-SFO
$79
7/4dj.
nonstopAlaska Airlines
2h 35mONT-SEA
$99
8/30dv.
1 stopDelta
10h 32mONT-DFW
$108
8/7dc.
1 stopAlaska Airlines
8h 25mONT-DFW
$109
7/2dt.
1 stopDelta
9h 14mONT-EWR
$128
8/15dj.
1 stopUnited Airlines
7h 00mONT-LGA
$133
8/15dj.
2 stopsUnited Airlines
10h 11mONT-LGA
$138

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Last minute flights from Ontario to the United States

Last minute flight, train and bus deals

6/6dj.
nonstopFrontier
1h 06mONT-LAS
6/8ds.
nonstopFrontier
1h 10mLAS-ONT
$85
6/7dv.
nonstopFrontier
1h 11mONT-LAS
6/14dv.
nonstopFrontier
1h 10mLAS-ONT
$86
6/6dj.
multi-stopAmerican Airlines
8h 31mONT-ORD
6/9dg.
multi-stopAmerican Airlines
5h 42mORD-ONT
$260
6/5dc.
multi-stopAmerican Airlines
6h 29mONT-SFO
6/8ds.
multi-stopAmerican Airlines
6h 28mSFO-ONT
$272
6/4dt.
multi-stopDelta
6h 12mONT-ORD
6/19dc.
multi-stopDelta
6h 22mORD-ONT
$279
6/4dt.
multi-stopDelta
9h 50mONT-LGA
6/8ds.
multi-stopDelta
11h 07mLGA-ONT
$291
6/6dj.
nonstopUnited Airlines
1h 25mONT-SFO
6/10dl.
nonstopUnited Airlines
1h 32mSFO-ONT
$324
6/5dc.
nonstopUnited Airlines
1h 25mONT-SFO
6/8ds.
nonstopUnited Airlines
1h 32mSFO-ONT
$369
6/4dt.
multi-stopAlaska Airlines
7h 19mONT-SEA
7/24dc.
nonstopAlaska Airlines
2h 35mSEA-ONT
$371
6/4dt.
multi-stopAlaska Airlines
10h 38mONT-HNL
6/16dg.
multi-stopAlaska Airlines
9h 55mHNL-ONT
$391

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Ontario - United States Flights

Departure:

Ontario (ONT)United States

Return flight deals:

United States - Ontario

Cabin classes:

$382
$153
$274
$36

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