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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 7/24. 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
lun. 5/27
lun. 6/3

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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 York2 stops$191
Los Angeles
Los Angeles1 stop$122
Las Vegas
Las Vegasnonstop$43
Miami
Miami1 stop$168
San Francisco
San Franciscononstop$48
Chicago
Chicago1 stop$115
Boston
Boston1 stop$248
Denver
Denvernonstop$58
Seattle
Seattlenonstop$68
Fort Lauderdale
Fort Lauderdale1 stop$284
Atlanta
Atlanta1 stop$147
Dallas
Dallasnonstop$79
Tampa
Tampa1 stop$115
Houston
Houston1 stop$93
Honolulu
Honolulu1 stop$319
San Diego
San Diego1 stop$329
Philadelphia
Philadelphia1 stop$142

Good to know

Low season

January

High season

July

Cheapest flight

$37
Best time to beat the crowds with an average 13% drop in price.
Most popular time to fly with an average 8% increase in price.
Flight from Ontario to Phoenix Sky Harbor Airport

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 - $138 round-trip; Dallas $132 one-way - $266 round-trip; Las Vegas $37 one-way - $68 round-trip
  • Morning departure is around 6% 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 9117 reviews
8.6crew
7.3entertainment
7.3food
7.9comfort
8.2boarding
Airline reviews

The WIFI didn't work well enough to get through even 5 minutes of a movie I had selected (it just kept pausing and spinning), and I just gave up and read a book. The selection of movies was a little sparse though, so reading wasn't that bad of an option. This was an older 737-800, with undersized overhead bins -- but it doesn't make sense to me that we are told to slide our bags in with the wheels facing us (most people ignore that and put the handles facing us). This makes it more difficult to remove the bags (no handle). The flight went well, and the fruit/cheese platter I pre-ordered was good -- although it is a little annoying to have to pre-order for this (but I suppose it saves time). When I pre-order it automatically gets charged to my personal credit card (Alaska VISA), when I'd prefer to use my corporate card for that on business trips.

8.0 ExcellentAnonymous, Apr 2024SNA - SEA
Read more about Alaska Airlines reviews

The WIFI didn't work well enough to get through even 5 minutes of a movie I had selected (it just kept pausing and spinning), and I just gave up and read a book. The selection of movies was a little sparse though, so reading wasn't that bad of an option. This was an older 737-800, with undersized overhead bins -- but it doesn't make sense to me that we are told to slide our bags in with the wheels facing us (most people ignore that and put the handles facing us). This makes it more difficult to remove the bags (no handle). The flight went well, and the fruit/cheese platter I pre-ordered was good -- although it is a little annoying to have to pre-order for this (but I suppose it saves time). When I pre-order it automatically gets charged to my personal credit card (Alaska VISA), when I'd prefer to use my corporate card for that on business trips.

Good - San Jose security is a breeze. Exact opposite of San Diego. Flight on time. Bad - FA's were not that cheery or polite. I thought we may blow out a tire as the pilot slammed down a hard landing in perfect conditions. He came in pretty hot like he had a date waiting.

It was our baby’s first flight and everything went perfect. The flight attendant gave him his first set of wings and we were smooth flying from there.

The messaging about the change in flight destination and options for getting to SFO was poor. There should have been frequent updates. When I spoke to the boarding agent moment before we were supposed to board, he was flippant and offered no help before the announcement was made that transportation would be arranged. It was as poor of an experience that I've ever had.

My plane ride down landed 20 min late. Boarding at SFO was strange too. The people at the terminal were nice—but, boarding lacked direction, and was confusing . Coming back was worse—the plane was hours behind—and I barely caught the last Bart train back to San Francisco (3 min more and I would have been in trouble). It was a very stressful trip, and it didn’t need to be.

This leg was better than the previous leg mostly because I upgraded my searing and the crew was nicer

I like that we took off on time and arrived a bit early. I like that I could gate check my bag and board early. I don't like how crowded the flight was. I had ok leg room, but could feel every move of the person next to me. And the aisles are very narrow. The gate and flight crews were terrific.

I appreciated the ability to choose between multiple flights both into and out of Portland from Burbank on the same day, so we were able to attend an event and return without spending the night. I am unable to appreciate what Alaska Air calls "streamlining" the checkin/boarding process at Burbank Airport. If you have a smartphone and the Alaska Air app, it is probably fine, but removing the option of using onsite kiosks to print boarding passes does not meet my definition of "streamlined". I also found it challenging that both Portland and Burbank airports required the plane to sit on the runway for some time due to lack of an open gate at which to disembark. It would not be so bad if we could at least remove our seat belts and move a little bit while we waited, but that is not an option. I honestly don't know whether this is because of how Alaska Air operates, or just the circumstances of the particular day and airports we were using, but I normally do not experience these kinds of delays to reach a gate using Southwest Air.

This flight was significantly affected by poor wifi connections. I couldn’t get my work done because the wifi kept dropping. Even texts were not going through. There is no seat power in premium class either. I fly a lot. Today was my 10th flight in 4 weeks. This was by far the only flight that was sub par.

the departure got delayed due to SJC situation, but it was a quite good waiting thanks to Alaska airline teams.

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

I guess they don’t serve drinks on planes anymore

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

Packed in like sardines, very uncomfortable. Sitting the aisle my shoulder was rammed into numerous times by rushing flight attendants. Also flight was very cold.

the head jack on my seat didn't work and the power outlet didn't work for my seat

Left 2 hours later for delayed I had to take care a kid with special need since people don’t want to move to accommodate the rest of the family. . It wasn’t bad but that made me upset that people can be that selfish.

For a 22 minute flight all you expect is for it to be safe and comfortable

Flight was on time. Staff were friendly. I paid for Economy Plus but was required to check my standard carry-on luggage due to lack of space on the aircraft. This cost me 30 minutes, unexpectedly, in waiting at the baggage claim. This experience did not meet my expectations.

Wouldn’t let me check in said couldn’t find a ticket had to wait very long Time

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 From PHX to CVG was on time, very professional staff

Flight was delayed and missed connecting flight. Did not give warning about delay until we showed up at the airport. Not good.

I purchased a carry on bag online…was supposed to cost $72 but after a whole slew of bs charges, the total was over $175.00. Because of these hidden charges, I will not even consider flying Frontier ever again. It’s just not worth the hassle. I’m scratching this company off my list forever.

Flight was OK. Seats were good no cell phone charges on the plane no TVs or entertainment.

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.

Flight cancelled and was told by a rude gate agent that they don’t accommodate on other airlines. Had to wait 5 hours for a connecting flight that had a 7 hour layover. Would not allow bags to be checked early so we couldn’t go through security .Had to rent a car for the afternoon to store bags and get a meal. Also incurred a hotel fee. No apology or reason given for the cancellation- just rudeness.

They cancelled the flight then did nothing to help us rebook. It was awful - I won’t fly with them again

The process of buying the ticket and navigating all the hidden charges that Frontier throws at you was a terrible experience. The actual airport experience and flying was fine.

The truck that was refueling the plane drove away with the hose still connected to the plane and ripped part of the plane off with it

Not have to pay for every single item to take a flight. Seating and delays sucked.

Flight was cancelled and I had to spend the night in the airport lugging my suitcase around

If you don’t check in 24 hours in advance, they will charge you $110 to check your bag instead of the $30. I did not get an email with this information and did not check in. In addition, my flight home was cancelled at layover and I had to spend the night in the airport, and then have another layover at another airport before making it home. Will not fly frontier again.

Book cheap flights from Ontario to the United States

Recent round-trip flight deals

5/4sáb.
nonstopFrontier
1h 26mONT-PHX
5/7mar.
nonstopFrontier
1h 16mPHX-ONT
$48
5/7mar.
nonstopFrontier
1h 27mONT-SFO
5/14mar.
nonstopFrontier
1h 29mSFO-ONT
$48
5/25sáb.
nonstopAlaska Airlines
2h 41mONT-SEA
6/1sáb.
nonstopAlaska Airlines
2h 32mSEA-ONT
$177
6/12mié.
nonstopDelta
2h 47mONT-SEA
6/18mar.
1 stopDelta
4h 29mSEA-ONT
$196
5/18sáb.
nonstopDelta
3h 02mONT-SEA
5/20lun.
nonstopDelta
2h 39mSEA-ONT
$197
5/27lun.
nonstopAlaska Airlines
2h 45mONT-SEA
6/3lun.
1 stopAlaska Airlines
5h 24mSEA-ONT
$226
5/31vie.
nonstopUnited Airlines
1h 25mONT-SFO
5/31vie.
nonstopUnited Airlines
1h 32mSFO-ONT
$227
5/18sáb.
1 stopAmerican Airlines
5h 07mONT-HOU
5/20lun.
1 stopAmerican Airlines
5h 40mHOU-ONT
$253
9/10mar.
1 stopAmerican Airlines
7h 22mONT-LGA
9/17mar.
2 stopsAmerican Airlines
8h 51mLGA-ONT
$260
5/3vie.
1 stopUnited Airlines
9h 00mONT-HNL
5/5dom.
1 stopUnited Airlines
7h 31mHNL-ONT
$340

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Recent one-way flight deals

7/24mié.
nonstopFrontier
1h 28mONT-PHX
$37
6/29sáb.
nonstopFrontier
1h 28mONT-SFO
$37
5/21mar.
nonstopDelta
3h 00mONT-SEA
$89
5/11sáb.
nonstopAmerican Airlines
3h 01mONT-DFW
$90
6/5mié.
1 stopDelta
4h 56mONT-DEN
$98
6/5mié.
1 stopAlaska Airlines
8h 07mONT-DEN
$100
5/29mié.
1 stopUnited Airlines
4h 40mONT-SEA
$101
8/20mar.
1 stopAmerican Airlines
10h 01mONT-LGA
$108
5/21mar.
1 stopAlaska Airlines
7h 31mONT-ORD
$110
6/26mié.
nonstopUnited Airlines
2h 17mONT-DEN
$120

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Last minute flights from Ontario to the United States

Last minute flight, train and bus deals

5/1mié.
nonstopFrontier
1h 27mONT-SFO
5/7mar.
nonstopFrontier
1h 29mSFO-ONT
$89
5/2jue.
nonstopFrontier
1h 27mONT-SFO
5/9jue.
nonstopFrontier
1h 29mSFO-ONT
$99
4/30mar.
multi-stopDelta
9h 24mONT-DFW
5/11sáb.
multi-stopDelta
8h 33mDFW-ONT
$260
5/2jue.
multi-stopAmerican Airlines
7h 59mONT-JFK
5/8mié.
multi-stopAmerican Airlines
10h 29mJFK-ONT
$274
4/29lun.
multi-stopDelta
7h 45mONT-LGA
5/6lun.
multi-stopDelta
10h 02mLGA-ONT
$276
5/2jue.
multi-stopAmerican Airlines
7h 59mONT-JFK
5/6lun.
multi-stopAmerican Airlines
10h 30mJFK-ONT
$281
5/2jue.
nonstopAlaska Airlines
2h 38mONT-SEA
5/9jue.
nonstopAlaska Airlines
2h 33mSEA-ONT
$312
5/2jue.
nonstopAlaska Airlines
2h 46mONT-SEA
5/2jue.
nonstopAlaska Airlines
2h 33mSEA-ONT
$321
5/1mié.
multi-stopUnited Airlines
6h 54mONT-LGA
5/7mar.
multi-stopUnited Airlines
8h 41mLGA-ONT
$376
4/30mar.
multi-stopUnited Airlines
13h 29mONT-LGA
5/14mar.
multi-stopUnited Airlines
10h 38mLGA-ONT
$386

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Ontario - United States Flights

Departure:

Ontario (ONT)United States

Return flight deals:

United States - Ontario

Cabin classes:

$362
$153
$296
$39

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