ONT

$35 Find Cheap Flights from California to Ontario

This is the cheapest one-way flight price found by a KAYAK user in the last 72 hours by searching for a flight to Ontario departing on 6/6. 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.
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Cheap Flights from California to Ontario

 
Here are some of the best deals found on KAYAK recently from the most popular airlines for round-trip flights from California to Ontario that are departing in the next months. While these flights were available on KAYAK in the last 72 hours, prices and availability are subject to change and deals may expire.
Discover the best prices for you by selecting your travel dates on KAYAK.

Recent round-trip flight deals from California to Ontario

Wed, Jun 25 - Sun, Jun 29
United Airlines Logo
9:18 pm - 10:45 pmSFO-ONT
1h 27mnonstop
United Airlines Logo
6:10 am - 7:37 amONT-SFO
1h 27mnonstop
$57United Airlines
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Mon, Aug 18 - Thu, Aug 28
Frontier Logo
10:11 pm - 11:40 pmSFO-ONT
1h 29mnonstop
Frontier Logo
9:41 pm - 11:13 pmONT-SFO
1h 32mnonstop
$59Frontier
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Fri, Jul 11 - Sun, Jul 13
Frontier Logo
10:11 pm - 11:40 pmSFO-ONT
1h 29mnonstop
Frontier Logo
9:41 pm - 11:14 pmONT-SFO
1h 33mnonstop
$60Frontier
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Tue, Jun 24 - Tue, Jul 1
Southwest Logo
6:00 am - 7:25 amOAK-ONT
1h 25mnonstop
Southwest Logo
6:05 pm - 7:25 pmONT-OAK
1h 20mnonstop
$77Southwest
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Tue, Jun 24 - Tue, Jun 24
Southwest Logo
7:10 am - 8:10 amLAS-ONT
1h 00mnonstop
Southwest Logo
9:35 pm - 10:40 pmONT-LAS
1h 05mnonstop
$77Southwest
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Tue, Jul 8 - Fri, Jul 11
United Airlines Logo
4:16 pm - 5:43 pmSFO-ONT
1h 27mnonstop
United Airlines Logo
6:39 pm - 8:06 pmONT-SFO
1h 27mnonstop
$91United Airlines
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Wed, Jun 18 - Tue, Jun 24
Delta Logo
6:59 pm - 11:46 pmSMF-ONT
4h 47m1 stop
Delta Logo
6:00 am - 11:27 amONT-SMF
5h 27m1 stop
$197Delta
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Fri, Jun 13 - Wed, Jun 25
Delta Logo
6:59 pm - 11:46 pmSMF-ONT
4h 47m1 stop
Delta Logo
1:15 pm - 6:09 pmONT-SMF
4h 54m1 stop
$213Delta
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Tue, Jul 15 - Sat, Jul 19
Alaska Airlines Logo
3:21 pm - 11:59 pmMFR-ONT
8h 38m1 stop
Alaska Airlines Logo
4:00 pm - 12:08 amONT-MFR
8h 08m1 stop
$238Alaska Airlines
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Wed, Jul 16 - Fri, Jul 18
Alaska Airlines Logo
3:21 pm - 11:59 pmMFR-ONT
8h 38m1 stop
Alaska Airlines Logo
6:58 pm - 12:08 amONT-MFR
5h 10m1 stop
$240Alaska Airlines
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Good to know

Low seasonFebruary
High seasonJuly
Cheapest flight$35
Best time to beat the crowds but there is an average 1% increase in price.
Most popular time to fly and prices are also 10% lower on average.
Flight from San Francisco to Ontario

Flights from California to Ontario: the best tips from KAYAK users

Insights shared by verified travelers who flew the route from California to Ontario 
LarryFlew with SouthwestOAK-ONTMay 2024
Oakland AP was nice and clean. Highly recommend to fly into the Bay Area.
MichaelFlew with United AirlinesSFO-ONTMar 2024
Do not fly the late United flights. Every time I have done it the flight is very very late. I keep thinking “it couldn’t possibly happen again” and then it does. I should just drive my car instead of wasting my life on United airlines.

FAQs for booking flights from California to Ontario

  • How does KAYAK find such low prices on flights from California to Ontario?

    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 California to Ontario.

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

    KAYAK’s flight Price Forecast tool uses historical data to determine whether the price for a flight to Ontario from California 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 California to Ontario?

    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 Ontario with an airline and back to California with another airline.

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

    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 Ontario from California up to 3 days before/after your preferred dates. You can then pick the flights that suit you best.

Top 5 airlines serving from California to Ontario

Need help choosing which airline to fly with from California to Ontario? 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 10000 reviews
7.9Comfort
7.1Food
8.2Boarding
8.5Crew
7.1Entertainment
Airline reviews

Flight last minute delayed 2 hours for crew calling out sick

4.0 OkaySalina, May 2025PDX - ONT
Read more Alaska Airlines reviews

Flight last minute delayed 2 hours for crew calling out sick

It was my first time flying Alaska Airlines and first time flying from Santa Rosa airport. The staff was very professional and friendly. Their instructions were clear and any question was answered satisfactorily. My seat was comfortable and the in-flight beverage service very adequate for the duration of the flight. We arrived ahead of the scheduled landing time and deplaning was simple. I look forward to flying with Alaska again.

Flight attendant took my carefully folded coat and flung it across the aisle to the bin across the way. Where one of the passengers rescued it for me, because that just wasn’t right!!

the flight was delayed twice and then delayed from taking off.

I’m New to Alaska Airlines. I was not able to connect to WiFi on either leg of my flights to/from Santa Rosa. Otherwise, it was an enjoyable ride.

All good. Great food and entertainment when there isn’t any on a one hour flight

Flight was delayed twice, I was forced to check my bag, and the only offered water or apple juice on the flight

Alaska Airlines needs more bag tag kiosks and bag check-in stations in Seattle. A single entry point for the bag tag kiosks would be helpful. This alleviates lines forming at each individual kiosk, which causes traffic jams for people passing through.

The flight was delayed over two and a half hours thus causing me to miss my best friend’s funeral. All because the flight crew had to get more rest. That was the reason stated. I understand however very unfortunate. Glad everyone is well rested and resting in peace.

All good except both the outbound and return flights were delayed about 1 1/2 hrs.

It was a perfect flight in all aspects! Both legs!

Boarding process, crew were good. But the seats were so uncomfortable that was all I could focus on. I literally had to sit forward so that all 3 of us could fit in row. I will try to avoid Southwest in the future for any flights over 60 minutes.

Great flight, 47 passengers on a 180 seat plane. Stewardess was pleasant and cheerful.

Great experience flying Southwest. The crew was really kind and helpful, and very friendly with our toddler.

Plane late from DC to Austin 30 minutes. Crew made up much of the time enroute to San Diego.

Fine, but how to board on SW versus othrr airlines, is just lame. Goood staff though and all was solid otherwise.

Was as expected. Crowed planes. Too many carryons delaying takeoff. But the ride only took an hour and saved me a lot of time SFO is a not a great airport.

Was as expected. Crowed planes. Too many carryons delaying takeoff. But the ride only took an hour and saved me a lot of time SFO is a hell hole of an airport. It is the new LaGuardia. Everything Cobbled together. Security gates closed. Terri directional signage

I will be flying again Southwest Airlines. Friendly crew, comfortable and affordable.

The plane arrived 25 minutes late, and the Wi-Fi was slower than it usually is.

United out of SFO is having issues with catering so none of our meals were loaded on the plane and no offer of compensation for our tickets purchased was offered.

A bit rush for transit. Food and entertainment are not available

The gate was too far away for the connecting flight

Generally good. The aisles have gotten narrower which can slow down boarding. Flight crew was great! Healthier complimentary snacks would be appreciated. Due to earthquake in San Francisco we had to circle in air space for a bit but then had a smooth landing. I laud the flight crew for their patience ;)

The agents was very rude and they charged me $50 for a carry-on bag saying that it was too big and then I saw someone going on a plane with the same size bag as me

For the most part united was a good experience, how ever when they came by with the snacks and water, they completely passed by my wife and I. As we were in separate rows. On a 5 hr flight we were not offered water

Fantastic crew. Flight was delayed at last minute but we were given updates every 20 minutes and the crew was so friendly and considerate. I miss the touch screens on the back of the seats, wish they would bring that back though.

Awful. Worst airline I have ever been on. Crew were among the rudest people I have ever dealt with. United staff members were rude and disrespectful. My flight was delayed, causing me to miss a connecting flight. I understand things happen, but when staff start lying about what actually happened, that is when I have an issue. Just be honest, really it isn’t that hard. I’m being very honest with this review and I don’t find this difficult what so ever. In fact, because of United Airlines, my Christmas holiday was off to a really rocky start. As someone who has traveled across the world, it has only been United that I have had a truly awful experience.

Boarding always seems a bit chaotic. Seat spacing could leave more for leg room.

Good flight. On time. Boarding and seating was easy. Crew were really friendly, yet professional. Bathroom (by cockpit) was small but serviceable. Some the seats were showing some notable wear & tear, but were comfy. Very happy UA customer. TY! 🤛🏽💗

hahaha we are delayed for one hour plus.. but thx we arrived San Diego safe

Worst airline ever! The guy weighing my bag had his foot on the metal plate and when I called him out on it, I got this stupid little smirk. La is a scam and so is Spirit Airlines. All the flight attendants looked like they hated our flight just as much as we did.

Unclear pricing; ended up being charged an extra $52 just to get onboard

Spirit is awful. Too expensive for what you get. Stop nickel and diming.

would be great to get basic water, soda at least and stop charging for carry ons

Your crew is a representation of your Standards and Values. The crew from Seattle to LAX, was very disappointing. The crew was more interested in hanging out at the lobby area. Talking, laughing loudly and eating all the snacks. They did not do regular rounds to see if customers needed anything. This was a huge disappointment. I will no longer be flying with your airlines moving forward.

- flight attendants not very friendly. - Paid for WiFi and plane didn’t have it working , never got a refund.

We got to fly on the new airplane. Much better as it’s roomier and cleaner than before. Most Importantly it’s much more comfortable. I still can’t move the seat back but the extra space made up for it. I didn’t taste the food or drinks because they charge for everything so I didn’t bother. I didn’t experience the entertainment because I downloaded my own movies on my phone. The crew was great. The flight itself was smooth . No complaints.

I was comfortable because I upgraded. I would not have been comfortable in economy. It was a short flight so there was limited food service and no inflight entertainment.

I thought since I upgraded my seat I would get some perks. Free water, free snacks. Free carry on luggage.

The seats were hard molded plastic covered in plastic vinyl. And the scam to charge people extra to sit together. Don’t they know we can just ask someone to trade seats. And watching the staff separate young children from parents… super classy. We had to guilt them into offering up our seats. This companies policies suck. Don’t give them your money.

The seats were awful, hard plastic covered in sheet vinyl. The airline tries to scam you into paying extra to get seat together when the flight wasn’t full. They were going to separate a family with young children but my wife who had a row to herself gave up her seat so the young mom could be with her young boys. I’m never giving this airline my money again.

It was a short flight so no food or entertainment….

Frontier had yet another flight cancellation. Have never made a complete round trip with this airline without at least one leg getting cancelled. Miserable flights - dirty, uncomfortable planes that apparently always have issues since I've had multiple delays and cancellations with them.

Flight was delayed 3 times, would have been nice to have received text message instead of email notifications. Frontier app wasn’t even updated accordingly, no gate number disclosed. No agent at front desk of gate to inform of delay. Very confused and left if the dark

Everything went as planned. Crew was great. Seats were still not that comfortable.

They changed the timing , first delayed by 4 hours then went back to 40 mins late, we had to run back to airport to not miss our flight. This is ridiculous

No frills for sure. No gate announcements about flight delay, not even water to drink on the flight.

I loked walking out on the tarmac to board and no first class. I didn't like that they have no snacks or onboard wifi to bide your time.

The plane was clean, the crew was friendly and helpful. It’s a low cost airline so there was no food, drinks or in flight entertainment but we didn’t expect any of these things. In the room for improvement department, they should install USB ports in seats to charge mobile devices.

Everything you need to know for your flight to Ontario

Information on the airport you'll fly into in Ontario

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