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$33 Find cheap flights from Ontario to the United States

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 9/22. 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
Sat 8/24
Sat 8/31

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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$156
Las Vegas
Las Vegasnonstop$48
Miami
Miami1 stop$159
San Francisco
San Franciscononstop$48
Chicago
Chicago1 stop$134
Boston
Boston1 stop$260
Denver
Denvernonstop$58
Seattle
Seattlenonstop$58
Fort Lauderdale
Fort Lauderdale1 stop$260
Atlanta
Atlanta1 stop$161
Dallas
Dallasnonstop$58
Tampa
Tampa1 stop$161
Houston
Houstonnonstop$96
Honolulu
Honolulunonstop$270
San Diego
San Diego1 stop$237
Philadelphia
Philadelphia1 stop$160

Good to know

Low season

January

High season

July

Cheapest flight

$33
Best time to beat the crowds with an average 9% drop in price.
Most popular time to fly with an average 8% increase in price.
Flight from Ontario to San Francisco

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: Dallas $175 one-way - $283 round-trip; Las Vegas $37 one-way - $60 round-trip; Seattle $97 one-way - $140 round-trip
  • Morning departure is around 4% more expensive 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 9365 reviews
8.2Boarding
7.2Food
7.9Comfort
7.2Entertainment
8.6Crew
Airline reviews

Easy checki in and boarding. VERY clean seats and excellent service.

10.0 ExcellentKim, Jul 2024SMF - SAN
Read more about Alaska Airlines reviews

Easy checki in and boarding. VERY clean seats and excellent service.

Took off and landed at the correct airports so they did pretty good.

The crew was wonderful! They were friendly and funny. The plane was clean.

Flight attendant in front portion of flight was surly. Aisle way too narrow, seats a bit narrow as well. If a large person had been seated next to me they would have been touching me and that’s not acceptable.

If you paid through Kayak, you will end up in the middle seat with no option to switch to a window or isle seat for less than $125 more each way. You will also have to pay a lot of money for your luggage.

I don't understand why passengers are frequently told that they must check their carry-on luggage due to the full flight and we board and find there are multiple empty overhead cabins with space for our carry-on. Crew should be more accurate in their assessment of the space (they have radios and I assumed they were in communication with a crew member on the plan who could tell them that the spaces were full or that there were remaining spaces). We were told in no uncertain terms that any remaining passengers yet to board had to check their carry on because no space remained on the plane, but there were multiple spaces available (including some that were completely empty) when we boarded. As someone who travels with things I must have with me, I do not appreciate this misinformation which causes me delay because I have to wait at baggage claim to get my small carry-on.

The seats were comfortable, the overhead bins were ample, the staff was helpful, attentive, and friendly. I enjoyed free texting. However, I much prefer Southwest no reserved seats (take any unoccupied seat) and their policy of two checked bags free, and ability to freely change flights. The Alaska airplane was nicer and newer than the Southwest one. Overall, my Alaska Airlines flying experience was a very positive one.

I am extremely dissapointed with Alaska Airlines. I had two minors traveling along, I used the unaccompanied minor program to escort my kids and bring them to mom on the other side of the flight. Unfortunately they just left them at the gate on the other side and did not bring them to mom. The person working for the airline flat out just told the kids they were not going to bring them to mom and just left them sitting there at the gate!!! These are two kids traveling alone. This is horrible and security should have been called

Flight was excellent , crew were very helpful and kind. No entertainment was needed as it was an overnight flight. Keep up the great work. Thank you 😊

For a red-eye flight, it was overall okay. My biggest complaint is that my seat recline was broken and I paid more for a premium seat. That was disappointing.

My seat was changed at the last minute and I was moved to the last row, right next to the bathroom despite selecting my seat well in advance. I was also made to check my carry on due to space but when I got on the plane there was significant empty overhead space. Picking up my carry on from the luggage carousel added time to my trip which had already been extended due to delay.

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

This flight was 2.5 hours delayed due to crew issues. This meant that we arrived after 2 AM. Very very inconvenient and we were not really kept well informed.

United is today and old, the planes, the staff, the business processes. Yet they expect premium prices for a less than average flight experience. I should have remembered to stay away from them and will remember to stay away from them in the future since I'm traveling a lot again. In a nutshell, they suck eggs.

The entertainment wasn’t playing in the app or online.

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.

I did not enjoy continuously being lied to about the amount of time we would circle Chicago before deciding to redirect to Milwaukee. Then the amount of time we would sit on the ground in Milwaukee waiting for gas, or to take off again. Or the amount of time it would then take to get to Chicago again, or sit on the runway waiting for a gate. The whole time continuously hopefully we would make our connecting flight that kept getting delayed as well. Only to scramble and miss it. Enough with the BS. Tell me the truth. "Sorry, things are backed up and your probably not going to make your flight. You should rebook on the next flight now rather than wait." You'll never hear those words from an airline. Speaking of which. If the flight has been redirected and/or is seriously delayed, how about making the WiFi free for everyone so they get to rebooking and reserving hotel rooms while still in the air. You've inconvenienced me already and now you want me to pay $20 for Internet so I can try to make other plans. Absolutely disgusting!

Excellent. Attendants served preflight drinks and were courteous and nice.

It was great! It’s been awhile since I’ve flown American but this most recent experience reminded me how much I enjoy flying American. Organized. Informative. Efficient. Friendly. Can’t ask for much more, except my luggage got dinged up a bit. But that could have been the airport.

It was the worst experience ever. Cabin temperature cold, for which they did not have any blankets upon my asking. We paid $125 extra for each passenger to get extra space sits; the sits were ridiculously small, tight, and uncomfortable! The flight attendant dropped ice on me and my sister! All in all, American Airlines deserves below zero!

The flight was delayed two hours, with no information as to why. The gate also changed several times which was aggravating. Would not fly through DFW again.

The inability to be flexible when you need to change a Basic Economy flight, when your company demands you book through a third party, causes raw feelings about the whole experience. A major airline should realize business and personal plans change all the time. I must save my company money on travel. Even if you have to charge me for the change, I get it. But being so rigid with a policy is not the best customer service.

WiFi was down so no entertainment and I could not work either. The flight was Very turbulent at the end (the last 20 min felt like an eternity) I appreciated the pilot for getting us there safely. The flight attending in first class was kind and attentive to everyone.

The gate crew did try to help, however they lacked the information as to whether the flight will operate or not. Being delayed 6 hours and in a limbo on whether the flight will operate or not is not fun. The airline having staffing issues is not encouraging at all.

From check-in staff to in-flight staff, everyone was wonderfully kind

The A321(?) model of the flight for 5+hrs has no seat back screens. Getting the american airlines wifi experience to watch movies on your own devices is not the same.

Better than expected.on time. Friendly staff in NY however MYR not so nice.

The flight crew and flight attendants are poorly trained and demonstrate poor professionalism. They have a sloppy appearance and communicate with patrons poorly. It is embarrassing for them to be representatives of an airline and for them to be called professionals.

After 5 hours of delay, they cancelled the flight. Very disappointed

My flight to LA was cancelled. I waited at the airport for 3 hrs saying it was delayed and then all of a sudden it was cancelled. Frontier only gave me a voucher and refund but could not rebook me. Flights on other airlines were too expensive last minute. I had to drive down to LA and didn’t even take my return flight home since I had to drive. One of the worst airline experiences in my life. It’s crazy how airlines can just upend people’s plans just like that.

Flying Frontiier was extremely poor!! I paid for a7:15am flight on flight 1601 from PHL To Las Vegas and the delay was brutally, excruciatingly and disgustingly long (8 hrs). I arrived by Uber to PHL at 5:30 am and had to spend the entire 8 hr delay inside the airport. Even more atrocious was that the flight was delayed twice. On the phone with customer service for two hours and was not fully compensated. I feel taken advantage of with this airline. They offered a menial couched for another flight within 90 days to me and my husband who has never flown but this experience has made us almost 100% sure to not fly this airline and will suggest that others don’t either. We don’t want to book ever again, don’t want a menial voucher and I believe by standard and because the flight was delayed for 8 hours, I should be fully reimbursed for the entire round trip. There is no excuse why this should have ever occurred. After sharing my experience with others in Vegas and Philadelphia, I was told that Frontier airlines is notorious for long delayed flights, poor customer service and refusal to compensate people correctly. I’m very nervous to see what departing from Vegas to Philadelphia will bring.

I fly Frontier often and generally don't have any issues. For some reason, the Denver to Houston's George Bush Intercontinental (IAH) flight always needs to wait on the tarmac in Houston because a gate is not available after landing. I've been stuck for as little as 15 minutes and as much as a little over an hour. I know only fly the Frontier Denver to IAH route when there is not an available flight to Houston Hobby (HOU).

Flight was 3 hours late leaving. Poor communication from the staff about delays. Impossible to get in touch with customer service (by design). And it actually didn't come out to be much cheaper than a non-budget airline! Not worth the headache, I'm never flying Frontier again

I’ve never flown frontier without a flight getting canceled. I understand that things go wrong with planes, but all other airlines handle cancellations so well. Frontier becomes a dumpster fire if a problem appears for them.

The flight attendence were extremely rude and I am disabled

They wouldn’t let us on the flight even tho we were an hour early. No refund not even our bags that were prepaid

Book cheap flights from Ontario to the United States

Recent round-trip flight deals

8/6Tue
nonstopFrontier
1h 29mONT-LAS
8/13Tue
nonstopFrontier
1h 08mLAS-ONT
$48
8/7Wed
nonstopFrontier
1h 24mONT-SFO
8/13Tue
nonstopFrontier
1h 24mSFO-ONT
$48
8/10Sat
2 stopsAlaska Airlines
10h 34mONT-SFO
8/11Sun
1 stopAlaska Airlines
12h 45mSFO-ONT
$70
8/10Sat
2 stopsAlaska Airlines
10h 34mONT-SFO
8/11Sun
1 stopAlaska Airlines
9h 29mSFO-ONT
$81
8/23Fri
nonstopDelta
2h 50mONT-SEA
8/28Wed
nonstopDelta
2h 47mSEA-ONT
$167
9/4Wed
nonstopUnited Airlines
1h 33mONT-SFO
9/4Wed
nonstopUnited Airlines
1h 26mSFO-ONT
$174
8/22Thu
nonstopDelta
2h 41mONT-SEA
8/27Tue
nonstopDelta
2h 47mSEA-ONT
$187
10/31Thu
1 stopAmerican Airlines
9h 00mONT-EWR
11/2Sat
1 stopAmerican Airlines
7h 47mEWR-ONT
$218
8/24Sat
nonstopUnited Airlines
2h 16mONT-DEN
8/25Sun
nonstopUnited Airlines
2h 17mDEN-ONT
$237
8/20Tue
1 stopAmerican Airlines
8h 36mONT-EWR
8/28Wed
1 stopAmerican Airlines
7h 38mEWR-ONT
$238

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Recent one-way flight deals

9/22Sun
nonstopFrontier
1h 24mONT-SFO
$33
8/30Fri
nonstopFrontier
2h 20mONT-DEN
$33
9/25Wed
nonstopDelta
2h 50mONT-SEA
$69
9/13Fri
nonstopAlaska Airlines
2h 38mONT-SEA
$79
10/22Tue
1 stopAmerican Airlines
6h 30mONT-SFO
$99
10/9Wed
1 stopAlaska Airlines
6h 15mONT-DEN
$99
10/24Thu
1 stopUnited Airlines
4h 24mONT-SEA
$102
9/25Wed
nonstopUnited Airlines
1h 33mONT-SFO
$107
9/1Sun
1 stopDelta
5h 52mONT-DFW
$108
9/7Sat
1 stopAmerican Airlines
9h 09mONT-EWR
$109

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Last minute flights from Ontario to the United States

Last minute flight, train and bus deals

7/27Sat
nonstopFrontier
1h 17mONT-LAS
8/3Sat
nonstopFrontier
1h 08mLAS-ONT
$83
7/30Tue
nonstopFrontier
1h 26mONT-SFO
8/1Thu
nonstopFrontier
1h 22mSFO-ONT
$83
7/26Fri
multi-stopAmerican Airlines
7h 34mONT-LGA
8/15Thu
multi-stopAmerican Airlines
7h 55mLGA-ONT
$283
7/26Fri
multi-stopAmerican Airlines
7h 34mONT-LGA
8/13Tue
multi-stopAmerican Airlines
9h 10mLGA-ONT
$288
7/26Fri
multi-stopDelta
10h 54mONT-LGA
8/14Wed
multi-stopDelta
7h 13mLGA-ONT
$293
7/26Fri
multi-stopDelta
11h 44mONT-LGA
7/30Tue
multi-stopDelta
11h 39mLGA-ONT
$298
7/29Mon
multi-stopUnited Airlines
9h 15mONT-SEA
9/14Sat
multi-stopUnited Airlines
5h 00mSEA-ONT
$372
7/26Fri
multi-stopUnited Airlines
12h 01mONT-LGA
8/15Thu
multi-stopUnited Airlines
13h 51mLGA-ONT
$383
7/29Mon
multi-stopAlaska Airlines
8h 39mONT-JFK
8/20Tue
multi-stopAlaska Airlines
15h 50mJFK-ONT
$526
7/30Tue
multi-stopAlaska Airlines
8h 39mONT-JFK
8/31Sat
multi-stopAlaska Airlines
11h 04mJFK-ONT
$531

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Ontario - United States Flights

Departure:

Ontario (ONT)United States

Return flight deals:

United States - Ontario

Cabin classes:

$358
$153
$296
$35

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