$28 Find Cheap Flights from Ontario to California - Compare and Save

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 California departing on 9/3. 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 Ontario to California

Cheapest round-trip prices found by our users on KAYAK in the last 72 hours
Los Angeles
Los Angeles1 stop$122
San Francisco
San Franciscononstop$92
San Diego
San Diego1 stop$119
San Jose
San Josenonstop$117
Palm Springs
Palm Springs1 stop$403
Fresno
Fresno1 stop$195
San Luis Obispo
San Luis Obispo1 stop$279
Bakersfield
Bakersfield1 stop$474
Arcata
Arcata1 stop$304
Redding
Redding1 stop$386
Reno
Reno1 stop$204
Los Angeles
Los Angeles1 stop$122
San Francisco
San Franciscononstop$92
San Diego
San Diego1 stop$119
San Jose
San Josenonstop$117
Palm Springs
Palm Springs1 stop$403
Fresno
Fresno1 stop$195
San Luis Obispo
San Luis Obispo1 stop$279
Bakersfield
Bakersfield1 stop$474
Arcata
Arcata1 stop$304
Redding
Redding1 stop$386
Reno
Reno1 stop$204

Book Cheap Ontario to California Plane Tickets

 
Here are some of the best deals found on KAYAK recently from the most popular airlines for round-trip flights from Ontario to California 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 Ontario to California

Fri, Sep 4 - Mon, Sep 14
Frontier Logo
8:48 am - 10:15 am
ONT
-
SFO
1h 27mnonstop
Frontier Logo
12:31 pm - 2:00 pm
SFO
-
ONT
1h 29mnonstop
$92Frontier
Fri, Aug 7 - Wed, Aug 12
Frontier Logo
8:58 am - 10:25 am
ONT
-
SFO
1h 27mnonstop
Frontier Logo
11:15 am - 12:48 pm
SFO
-
ONT
1h 33mnonstop
$93Frontier
Fri, Aug 21 - Mon, Aug 24
Frontier Logo
8:48 am - 10:15 am
ONT
-
SFO
1h 27mnonstop
Frontier Logo
9:33 am - 11:02 am
SFO
-
ONT
1h 29mnonstop
$94Frontier
Wed, Aug 12 - Wed, Aug 19
Southwest Logo
6:25 pm - 7:35 pm
ONT
-
SJC
1h 10mnonstop
Southwest Logo
5:05 pm - 6:25 pm
SJC
-
ONT
1h 20mnonstop
$117Southwest
Sat, Sep 5 - Sun, Sep 6
Southwest Logo
4:40 pm - 5:55 pm
ONT
-
SJC
1h 15mnonstop
Southwest Logo
7:45 am - 9:00 am
SJC
-
ONT
1h 15mnonstop
$122Southwest
Wed, Aug 19 - Tue, Aug 25
Alaska Airlines Logo
4:27 pm - 6:07 pm
ONT
-
STS
1h 40mnonstop
Alaska Airlines Logo
2:09 pm - 3:47 pm
STS
-
ONT
1h 38mnonstop
$157Alaska Airlines
Wed, Sep 16 - Mon, Sep 21
Alaska Airlines Logo
4:27 pm - 6:07 pm
ONT
-
STS
1h 40mnonstop
Alaska Airlines Logo
2:09 pm - 3:47 pm
STS
-
ONT
1h 38mnonstop
$160Alaska Airlines
Wed, Aug 12 - Fri, Aug 14
United Airlines Logo
6:08 am - 9:33 am
ONT
-
SMF
3h 25m
1 stop
United Airlines Logo
6:57 pm - 10:59 pm
SMF
-
ONT
4h 02m
1 stop
$184United Airlines
Fri, Aug 28 - Sun, Aug 30
United Airlines Logo
6:08 am - 10:15 am
ONT
-
MRY
4h 07m
1 stop
United Airlines Logo
6:45 pm - 10:59 pm
MRY
-
ONT
4h 14m
1 stop
$279United Airlines
Thu, Aug 27 - Sun, Aug 30
American Airlines Logo
12:59 pm - 7:20 pm
ONT
-
MFR
6h 21m
1 stop
American Airlines Logo
5:20 am - 12:03 pm
MFR
-
ONT
6h 43m
1 stop
$339American Airlines
Booking Insights

KAYAK's insights & trends for Ontario to California flights

Get data-powered insights and trends into flights from Ontario to California to help you find the cheapest flights, the best time to fly and much more.

What is the cheapest Ontario to California flight route?

Data is based on round-trip flight searches on KAYAK over the past month.

The cheapest ticket to California from Ontario found in the last 5 days was to San Francisco, at $71 round-trip. The most popular route is from Ontario (ONT) to San Francisco (SFO), and the cheapest round-trip airline ticket found on this route in the last 5 days was $71.

Can I save money by flying with a layover from Ontario to California?

The average round-trip price for all non-stop flights, flights with one layover, and flights with two layovers for the route found by users searching on KAYAK in the last 2 weeks.

No, with an average price for the route of $335, prices are generally cheapest when you fly direct.

What is the cheapest month to fly from Ontario to California?

To calculate monthly average prices, KAYAK takes all prices for each month over the last year for round-trip flights from Ontario to California, removes the top 0.1% to account for outliers, and then takes the median of all values for each month.

The cheapest month for flights from Ontario to California is April, when tickets cost $28 (return) on average. On the other hand, the most expensive months are October and September, when the average cost of round-trip tickets is $368 and $310 respectively.

Good to know

Low seasonJanuary
Cheapest flight$28
Best time to beat the crowds but there is an average 24% increase in price.
Most popular time to fly and prices are also 15% lower on average.
Flight from Ontario to San Francisco

FAQs - booking California flights

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

    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 California.

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

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

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

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

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

Top tips for finding cheap flights to California

  • Looking for a cheap flight? 25% of our users found tickets from Ontario to the following destinations at these prices or less: Las Vegas $151 one-way - $201 round-trip; San Francisco $145 one-way - $163 round-trip; Sacramento $153 one-way - $274 round-trip

Reviews of the top 5 airlines serving from Ontario to California

 
See real verified KAYAK customer reviews for airlines flying from Ontario to California. Airline scores are aggregated from all reviews left by passengers on KAYAK after flying with an airline. KAYAK doesn’t show reviews that are older than 5 years. Learn how KAYAK collects reviews.
Need help choosing which airline to fly with from Ontario to California? 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
SouthwestOverall score based on 4250 reviews
8.6Crew
8.0Comfort
7.5Entertainment
7.0Food
8.1Boarding
Airline reviews

Flight was delayed, full flight and I had to change gates. Southwest flights are always late later in the day.

4.0 OkaySteven, Jun 2026
ONT - LAS
Read more Southwest reviews

Flight was delayed, full flight and I had to change gates. Southwest flights are always late later in the day.

Boarding was easy. The seats are small and fairly uncomfortable

The problem with the seat assignments is that there were a lot of rows in the front that were empty but my row at the back was full. Just not so pleasant.

Good but I prefer choose your own seat. With the new assigned seats they should board from the back I see no advantage to this new boarding. Just like every other airline

The charges were ridiculous for an hour flight and the turbulence was very scary.

3 hour delay. Had to change plans and was still delayed.

The boarding and seat assignment system no longer works for me, but I know it is being replaced. Otherwise, I am good with the overall experience.

The lead steward kept singing about "San Francisco" and hotel California---more annoying than humorous....needs work. Flight was smooth and on time.

San Diego airport is brand new, spacious, airy and very smooth checkin at SW baggage drop.

I liked receiving attention from aged and well experienced flight attendants. I disliked the non-gluten-free snack but I brought my own so I was OK.

The seat on row 11 was a little hard cause my butt was hurting a little bit from sitting after and hour.

The first flight was fine, great crew, but the plane was delayed 45 minutes to go to Seattle because of they were missing a ramp. That would make sense if the plane was actually at the gate. Not if we’re still waiting for a plane. After we landed we waited 30-45 minutes on the tarmac just to get off the plane. Alaska made me miss my connecting flight, wasting my time, and my money. I should honestly be reimbursed, but hey, when does the airline ever actually take accountability? Never.

Wish there were more complimentary drinks available - only had water and apple juice. Also - no snacks were provided during the flight, but we were offered some items as we exited the plane.

My daughter has anxiety and became nauseous after boarding the plane and before take off. She went to the plane bathroom and ended up having to vomit, and your staff promptly removed us from the flight. We explained that it was due to my daughter’s anxiety, and that the condition would not continue in the air, but they removed us anyway. We have flown many many times before on many different airlines and my daughter’s anxiety has resulted in nausea and sickness before takeoff, and every airline has been accommodating and professional. This is was our first time flying with your airline, and also the first time we have ever been removed from a flight. This was the worst service we have ever experienced. This was a special surprise trip we gifted to my daughter for graduating college. I had also paid to upgrade the family to first class and sit all together which we had never done before and can’t afford on a normal basis. Our removal from the flight was not only extremely embarrassing, but devastating for my daughter. My daughter and I were removed from the plane and a call was made by your staff to medical personnel, a few questions were asked of my daughter, and then she was magically cleared. All of this took mere minutes. Why this could not have been performed while we were on the plane, or why this could not have been performed off the plane and then us allowed to reboard is beyond me. My wife and youngest daughter continued on the original flight alone and were very upset and crying due to the situation, yet the staff did nothing to console or assist them. My wife states that upon arrival in Portland and as they were exiting the plane, one of the stewardesses involved said “byyyyeeeee” to them sarcastically and laughed. Myself and my oldest daughter had to wait 4 hours for an alternate flight and were sat in regular seats because our first class seat purchase could not be honored. My wife wasn’t allowed to pick up our rental car and had to wait 4 hours with our luggage until I arrived. The delay prevented us from being able to carry out planned events and ruined the first day of our trip. Upon explaining all of this to your customer service, we received no sympathy, assistance, or compensation other than your staff submitting a request for a reimbursement of my and my daughters first class upgrade cost. When checking in early for our flight back home, the luggage cost for myself and my eldest daughter was no longer discounted as it was for my wife and youngest daughter. Customer service once again could not assist me over the phone and rectify what should have been a minor adjustment. Instead they stated I would have to wait until we physically checked bags in at the airport and then ask staff to adjust the luggage cost. With everything else we had experienced, I was not going to leave that to chance and instead paid full price for the luggage ahead of time. Or experience with Alaska Airlines was a complete disaster and I am baffled at the lack of empathy and assistance from your staff. I’m not sure of what else to say other than the fact that unless we are compensated by Alaska Airlines in some form to offset the horrendous service we received, we will be relaying our experience to family and friends and on social media, and doing all we can to urge everyone to avoid utilizing your services.

I got an email 3 hours before the flight letting me know it got canceled

Boarding was easy and quick. Staff was very friendly. Service of snacks and drinks by staff was outstanding.

It was ok! Not fond of sitting in middle seat. Tried to upgrade with my Atmos card but it was a new account and they weren’t able to look up my account details.

Not bad. Due to not buying a seat, on the way back, my seat was not assigned till 2 hrs before the flight left. Got me worried I wouldn’t have a seat.

There is no entertainment on the plane. The snack is minimal. The crew was nice and professional.

The first leg of the trip was excellent. Lovely flight attendants and comfortable plane. The second leg left a lot to be desired. The flight attendant was rude when I asked for a Diet Coke, the boarding required quite a long walk and the plane was crammed and uncomfortable.

It was a short, comfortable flight. It did leave an hour late due to the pilot having to be replaced (family emergency) but that didn’t inconvenience myself & my friend. The situation was explained, eventually.

UA594 was delayed multiple times. I ended up getting picked up so I can make it in time for work 6AM on Monday, 7/6/2026

Service was professional and quick. Premium economy seat was comfortable given the class

The staff was extremely helpful and friendly at all times! They went above and beyond to get us into an earlier flight in San Diego to make our connection in SFO possible, because our original flight did actually not make it! I did so much appreciate the UA team and how they made this possible. We also didn’t have seats together on the long flight to Singapore, but they found us seats together last moment with no additional cost! Nobody sat next to us, so that we were able to sleep! Thanks to UA for improving their service and Underpricer for booking this trip! Please be careful: 1,5 hrs for transfer in San Francisco might not be enough time in the future

Seat pitch is horrible especially on the 15 hour flight. Gate crew at SFO was Outstanding. The flight crew was also great.

Late plane. Only one crew on the ground so we b had to wait for Denver flight to come in, board, and depart. At 78 yrs of age I was not pleased trying to get my connection. What really made me angry was the notification you sent me to hurry up or I would miss my connection. Why tell me to hurry up when you got me in late. It was not a good way of treating customers.

Outstanding service, efficient & friendly crew, flight was safe, comfortable & on time

Flight delayed for more than 16 hrs and no effort was spent to provide an alternate

it was a very short flight so my expectations were low.

Very disappointing given gate agent behavior. Filed a formal complaint with United.

I was able to check into my flight through the app and online but had issues getting my boarding pass once I arrived to the airport.

I don’t like the music section but I believe it was a cost decision. I changed my flight last minute due to work issues and had to sit way in the back. The seats were way closer together than I would have preferred.

Ontario airport boarding was very easy to park and access, is clean and TSA took 10 minutes total. Check-in was a breeze and cruise was very nice.

Good flight, seated and had a water within 5 minutes. Crew was hospitable.

The experience at checkin for my American Airlines flight from Sacramento to LAX was very good including the assistance I received in getting my bags checked in and boarding passes printed. Was pleasantly surprised the my bags were checked through all the way to my destination at Clark International Airport in Angeles, Philippines.

The flight was on time and arrived early. The crew were friendly and helpful.

The chair cushions may need an upgrade. I have been noticing they are so worn out, thin so you’d sit in a dip 😄. Other than that, all was an enjoyable trip. Thanks AA!

VERY disappointed at the agent checking in my luggage. I know that the weight limit is 23 kg, a little over 50 pounds (50.71 pounds). Yet the agent kept repeating "50 pounds". So I said, the limit is 23 kg, and she had the audacity to say 'no, it is 22 kg!" Imagine my surprise. Was she ignorant or was she poorly trained? Not sure. The boarding process was pretty good. The speakers were loud enough so I still could hear them despite inconsiderate passengers continuing to speak while the announcements were going on. During the flight, the teenage girl sitting behind me kept pressing her feet to the back of my chair. I turned around several times, yet she did not get the hint. I did not make a fuss since I sense I had a bad streak that night with AA, so I just did the best I can to lean forward and not let that bother me.

It was wonderful upgrading to first. Plane was so cold thou. Crew was great. Wish there was a food option in first for such a long flight. Doesnt matter the time of day. Chintzy.

The flight landed at LAX we were then bussed to collect our bags. That process took nearly as long as the flight. Luckily we weren't in a hurry!

I really didn't like anything. Paid for my checked luggage online ($79) and then was told that I would have to paid another $79 for my carry on. Was not allowed to enter the terminal until 3 hours before my flight and when I finally was allowed to check my bag and enter, my flight was delayed 3 times. When I finally landed, we were all instructed to "run off the plane" as they had to do a quick turn around to Las Vegas. Me and several of my flying companions will never fly Frontier again.

The takeoff was the smoothest I've ever experienced on any airline and this is the first time I've flown on frontier so this was an extremely pleasant surprise!

A lady asked to stop the flight after the tunnel pulled away and we began to depart a flight that was already hours late. The attendance respectfully stopped the the plane and had the tunnel return. After the tunnel returned the passenger claimed to have changed her mind . The tunnel was then put in reverse and the passenger remained on the plane .. They should have sent the sick passenger off the plane like initially replaced. They existed a couple off the plane prior to that situation.. So.. all and all.. it was a long and flight.. .

We understand and comply with Frontier’s bag sizes. We’ve had some problems in past while having to await other passengers who do not understand the baggage restrictions or have not prepaid and that is usually our biggest concern (others delaying us) with flying Frontier. Flying OUT of ONT, however, has always been a great experience. I’ve also noted even on delayed Frontier flights very knowledgeable pilots who manage expectations well.

Long lines, rude staff, everything that's offered you have to pay for.

The last time I flew Frontier was in the 1960s when it was a “real” airline. We flew this time because of the price & schedule. As the saying goes, you get what you pay for.

I appreciated the upgrade to free cary-on bag and seat selection at no charge

Flight was delayed on the runway for 40 minutes the crew did not even offer even water to passengers to compensate for the flight delayed. The flight was delayed due to aircraft mechanical issues. Worst customer service ever

This isna terribly run airlines. If you're one minute late, they will deny your ticket. Don't waste your time or money

Flight was delayed for more than 3 hours, crew at ONT airport was rude, and when we got to DFW the airplane had an issue landing, we had to be taxied to the terminal, and the luggage was hold until the next day.

Everything you need to know for your flight from Ontario to California

Information on your arrival and departure airports