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Find cheap flights from Ontario to the United States from $34

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 5/23. 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
Sun 6/2
Sun 6/9

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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$179
Las Vegas
Las Vegasnonstop$46
Miami
Miami1 stop$226
San Francisco
San Franciscononstop$36
Chicago
Chicago1 stop$136
Boston
Boston1 stop$274
Washington, D.C.
Baltimore1 stop$179
Denver
Denvernonstop$58
Seattle
Seattlenonstop$88
Fort Lauderdale
Fort Lauderdale1 stop$260
Atlanta
Atlanta1 stop$178
Dallas
Dallasnonstop$76
Tampa
Tampa1 stop$180
Houston
Houstonnonstop$88
Honolulu
Honolulu1 stop$299
San Diego
San Diego1 stop$368
Philadelphia
Philadelphia1 stop$152

Good to know

Low season

January

High season

July

Cheapest flight

$34
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 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 $85 one-way - $135 round-trip; Dallas $138 one-way - $275 round-trip; Las Vegas $35 one-way - $66 round-trip
  • Morning departure is around 13% 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 9128 reviews
7.3Food
8.2Boarding
8.6Crew
7.9Comfort
7.3Entertainment
Airline reviews

Honestly, there was not much they could do. Due to wind, the flight was delayed for several hours because we had to be diverted to San Jose where we needed to refuel before departing to Hawaii. Wish they had offered some snacks during the delays/diversion because we had to wait such a long time to finally get our food served during the flight after leaving California.

4.0 OkayAnonymous, May 2024SAN - HNL
Read more about Alaska Airlines reviews

Honestly, there was not much they could do. Due to wind, the flight was delayed for several hours because we had to be diverted to San Jose where we needed to refuel before departing to Hawaii. Wish they had offered some snacks during the delays/diversion because we had to wait such a long time to finally get our food served during the flight after leaving California.

They canceled the flight 30 minutes prior to departure without any heads up.

All parts were excellent, especially staff at bag tag printing and inflight crew. Just the normal differences from past air travel could be improved but we’ve learned to accept those—cramped seats, minimal food/beverage, etc.

Better organizing of entry and exit onto the plane regarding all of the baggage people haul on. There should be a better system so those with no baggage can get in and out more quickly. The baggage haul-on situation is absurd.

Attentive crew. Best of all was the empty seat between me and my rowmate.

We had a very scary attempted landing in Palm Springs and were redirected to Ontario. It was a stressful flight.

Every thing means , crew, service, timing, boarding is very good.

I really like Alaska airline, it's my favorite airline❤️

Alaska Airlines was fantastic. Kayak on the other hand was extremely poor. I got tickets through Kayak for a flight to a funeral. The date got changed less than 12 hours after I made my reservations. When I attempted to change my flights through Kayak, I was unable to use either the website or the phone system. The phone matrix did not give an option to cancel or change. The website said Kayak could not find any record of me making airline reservations through Kayak and even through I never left the Kayak website when making the reservations to my knowledge. After more than a half hour of frustration on the phone and computer ( on top of dealing with the death of a member of my family) I finally contacted Alaska Airline directly and they cancelled my flight and refunded the cost very quickly and efficiently. Alaska Airlines gets 10 stars. Kayak gets zero stars and has permanently lost a customer. I will never use Kayak again.

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.

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

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

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.

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.

Six hour delay. Poor customer service. No voucher. Bad communication. Missed important appointments.

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.

Flight was canceled with little warning. Flight was rebooked through Ontario, California and connecting flight was delayed by over three hours. Frontier is living up to their Greyhound of the skies reputation for sure.

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

Book cheap flights from Ontario to the United States

Recent round-trip flight deals

6/1Sat
nonstopFrontier
1h 28mONT-SFO
6/4Tue
nonstopFrontier
1h 24mSFO-ONT
$38
5/28Tue
nonstopFrontier
1h 28mONT-SFO
6/4Tue
nonstopFrontier
1h 24mSFO-ONT
$39
6/1Sat
nonstopUnited Airlines
1h 25mONT-SFO
6/4Tue
nonstopUnited Airlines
1h 35mSFO-ONT
$169
6/12Wed
1 stopDelta
6h 59mONT-SEA
6/18Tue
1 stopDelta
4h 29mSEA-ONT
$176
7/18Thu
nonstopDelta
2h 49mONT-SEA
7/21Sun
nonstopDelta
2h 45mSEA-ONT
$197
5/24Fri
nonstopAlaska Airlines
2h 41mONT-SEA
5/27Mon
nonstopAlaska Airlines
2h 33mSEA-ONT
$217
5/22Wed
nonstopAmerican Airlines
3h 00mONT-DFW
5/29Wed
nonstopAmerican Airlines
3h 07mDFW-ONT
$219
6/1Sat
1 stopAmerican Airlines
5h 19mONT-HOU
6/8Sat
1 stopAmerican Airlines
5h 34mHOU-ONT
$248
5/14Tue
1 stopUnited Airlines
9h 00mONT-HNL
5/20Mon
1 stopUnited Airlines
8h 31mHNL-ONT
$299
5/7Tue
1 stopAlaska Airlines
18h 17mONT-HNL
5/9Thu
1 stopAlaska Airlines
13h 59mHNL-ONT
$360

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Recent one-way flight deals

5/23Thu
nonstopFrontier
1h 14mONT-LAS
$34
6/23Sun
nonstopFrontier
1h 27mONT-SFO
$34
7/3Wed
nonstopDelta
2h 44mONT-SEA
$79
6/4Tue
1 stopDelta
5h 06mONT-SEA
$88
7/1Mon
nonstopAmerican Airlines
3h 01mONT-DFW
$95
6/4Tue
1 stopAlaska Airlines
8h 07mONT-DEN
$100
5/30Thu
1 stopAmerican Airlines
6h 15mONT-SFO
$104
6/4Tue
1 stopAlaska Airlines
8h 49mONT-DFW
$104
6/1Sat
nonstopUnited Airlines
1h 25mONT-SFO
$115
5/29Wed
1 stopUnited Airlines
4h 40mONT-SEA
$119

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Last minute flights from Ontario to the United States

Last minute flight, train and bus deals

5/5Sun
nonstopFrontier
1h 10mONT-LAS
5/10Fri
nonstopFrontier
1h 02mLAS-ONT
$69
5/4Sat
nonstopFrontier
1h 14mONT-LAS
5/9Thu
nonstopFrontier
1h 02mLAS-ONT
$71
5/4Sat
multi-stopDelta
11h 38mONT-DFW
5/18Sat
multi-stopDelta
7h 45mDFW-ONT
$270
5/4Sat
nonstopAmerican Airlines
2h 57mONT-DFW
5/18Sat
nonstopAmerican Airlines
3h 06mDFW-ONT
$274
5/7Tue
multi-stopAmerican Airlines
8h 30mONT-JFK
5/11Sat
multi-stopAmerican Airlines
10h 32mJFK-ONT
$283
5/7Tue
multi-stopDelta
7h 54mONT-LGA
5/8Wed
multi-stopDelta
9h 07mLGA-ONT
$286
5/4Sat
multi-stopAlaska Airlines
9h 19mONT-ORD
5/7Tue
multi-stopAlaska Airlines
9h 00mORD-ONT
$322
5/7Tue
multi-stopAlaska Airlines
18h 17mONT-HNL
5/9Thu
multi-stopAlaska Airlines
13h 59mHNL-ONT
$360
5/4Sat
multi-stopUnited Airlines
6h 54mONT-LGA
5/11Sat
multi-stopUnited Airlines
8h 41mLGA-ONT
$386
5/8Wed
multi-stopUnited Airlines
9h 12mONT-LGA
5/11Sat
multi-stopUnited Airlines
8h 41mLGA-ONT
$419

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Ontario - United States Flights

Departure:

Ontario (ONT)United States

Return flight deals:

United States - Ontario

Cabin classes:

$358
$153
$296
$38

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