$39 Find Cheap Flights from Ontario to San Francisco Bay Area

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 San Francisco Bay Area departing on 10/16. 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
1 adult, Economy

KAYAK searches hundreds of travel sites at once for deals on flights to San Francisco Bay Area

 
These are the airlines KAYAK users have selected most often from within our search results in flight searches from Ontario to San Francisco Bay Area.
These are the airlines KAYAK users have selected most often from within our search results in flight searches from Ontario to San Francisco Bay Area.
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Flight Deals

Cheap Flights from Ontario to San Francisco Bay Area

Cheapest round-trip prices found by our users on KAYAK in the last 72 hours
San Francisco
San Franciscononstop$71
San Jose
San Josenonstop$97
San Francisco
San Franciscononstop$71
San Jose
San Josenonstop$97

Book Cheap Ontario to San Francisco Bay Area 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 San Francisco Bay Area 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 San Francisco Bay Area

Mon, Oct 20 - Thu, Oct 23
Frontier Logo
10:50 pm - 12:19 amONT-SFO
1h 29mnonstop
Frontier Logo
10:38 pm - 12:07 amSFO-ONT
1h 29mnonstop
$71Frontier
Find Deal
Wed, Oct 29 - Wed, Oct 29
United Airlines Logo
6:00 am - 7:24 amONT-SFO
1h 24mnonstop
United Airlines Logo
11:15 am - 12:37 pmSFO-ONT
1h 22mnonstop
$72United Airlines
Find Deal
Tue, Nov 4 - Tue, Nov 11
United Airlines Logo
6:00 am - 7:24 amONT-SFO
1h 24mnonstop
United Airlines Logo
9:30 pm - 10:51 pmSFO-ONT
1h 21mnonstop
$77United Airlines
Find Deal
Thu, Jan 8 - Mon, Jan 12
Frontier Logo
10:12 pm - 11:52 pmONT-SFO
1h 40mnonstop
Frontier Logo
10:03 pm - 11:31 pmSFO-ONT
1h 28mnonstop
$78Frontier
Find Deal
Tue, Nov 4 - Tue, Nov 11
Southwest Logo
10:15 am - 11:35 amONT-OAK
1h 20mnonstop
Southwest Logo
6:20 am - 7:40 amOAK-ONT
1h 20mnonstop
$97Southwest
Find Deal
Wed, Nov 5 - Wed, Nov 12
Southwest Logo
3:15 pm - 4:30 pmONT-SJC
1h 15mnonstop
Southwest Logo
10:35 am - 11:55 amSJC-ONT
1h 20mnonstop
$97Southwest
Find Deal
Sat, Nov 15 - Mon, Nov 17
American Airlines Logo
6:11 am - 12:48 pmONT-STS
6h 37m1 stop
American Airlines Logo
12:37 pm - 6:20 pmSTS-ONT
5h 43m1 stop
$236American Airlines
Find Deal
Sat, Jan 24 - Tue, Jan 27
American Airlines Logo
6:27 am - 12:25 pmONT-STS
5h 58m1 stop
American Airlines Logo
12:55 pm - 6:20 pmSTS-ONT
5h 25m1 stop
$237American Airlines
Find Deal
Wed, Nov 5 - Wed, Nov 12
Alaska Airlines Logo
4:11 pm - 10:05 pmONT-STS
5h 54m1 stop
Alaska Airlines Logo
2:22 pm - 8:53 pmSTS-ONT
6h 31m1 stop
$245Alaska Airlines
Find Deal
Wed, Nov 5 - Sat, Nov 8
Alaska Airlines Logo
6:00 am - 10:05 pmONT-STS
16h 05m1 stop
Alaska Airlines Logo
2:22 pm - 8:53 pmSTS-ONT
6h 31m1 stop
$253Alaska Airlines
Find Deal
Booking Insights

KAYAK's insights & trends for Ontario to San Francisco Bay Area flights

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

What is the cheapest Ontario to San Francisco Bay Area flight route?

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

The cheapest ticket to San Francisco Bay Area from Ontario found in the last 72 hours was to San Francisco, at $67 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 72 hours was $67.

Can I save money by flying with a layover from Ontario to San Francisco Bay Area?

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 $319, prices are generally cheapest when you fly direct.

What is the cheapest month to fly from Ontario to San Francisco Bay Area?

To calculate monthly average prices, KAYAK takes all prices for each month over the last year for round-trip flights from Ontario to San Francisco Bay Area, 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 San Francisco Bay Area is May, when tickets cost $89 (return) on average. On the other hand, the most expensive months are September and November, when the average cost of round-trip tickets is $159 and $159 respectively.

What’s the cheapest day of the week to fly from Ontario to San Francisco Bay Area?

The average price of all round-trip flights from Ontario to San Francisco Bay Area clicked on KAYAK for each day over the last 12 months.

If you are looking for a flight deal from Ontario to San Francisco Bay Area, look for departures on Fridays and avoid leaving on a Wednesday, as it's usually the priciest day. When flying back from San Francisco Bay Area, Monday is the cheapest day to fly and Wednesday is the most expensive.

How far in advance should I book a flight from Ontario to San Francisco Bay Area?

To calculate weekly average prices, KAYAK takes all prices for each week before departure over the last year for round-trip flights from Ontario to San Francisco Bay Area, removes the top 0.1% to account for outliers, and then takes the average of all the values for each week.

To get a below average price on the flight from Ontario to San Francisco Bay Area, you should book around 2 weeks before departure, which saves you about 27% compared to booking last minute. For the absolute cheapest price, our data suggests you should book 6 weeks before departure.

Good to know

Low seasonJanuary
Cheapest flight$39
Best time to beat the crowds but there is an average 4% increase in price.
Most popular time to fly with an average 17% increase in price.
Flight from Ontario to San Francisco

FAQs - booking San Francisco Bay Area flights

  • How does KAYAK find such low prices on flights from Ontario to San Francisco Bay Area?

    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 San Francisco Bay Area.

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

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

    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 San Francisco Bay Area 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 San Francisco Bay Area?

    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 San Francisco Bay Area up to 3 days before/after your preferred dates. You can then pick the flights that suit you best.

  • What is the cheapest time of day to fly to San Francisco Bay Area?

    The cheapest time of day to fly to San Francisco Bay Area is generally at night, when round-trip flights cost $113 on average. Morning departures are around 17% cheaper than evening flights, on average. The most expensive time of day to fly to San Francisco Bay Area is generally in the afternoon, which is peak travel time and where the average cost of a ticket is $259.

Top tips for finding cheap flights to San Francisco Bay Area

  • Looking for a cheap flight? 25% of our users found tickets from Ontario to the following destinations at these prices or less: San Francisco $72 one-way - $133 round-trip; San Jose $116 one-way - $208 round-trip

Reviews of the top 5 airlines serving from Ontario to San Francisco Bay Area

 
See real verified KAYAK customer reviews for airlines flying from Ontario to San Francisco Bay Area. 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 San Francisco Bay Area? 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 4237 reviews
8.0Comfort
7.0Food
8.1Boarding
7.5Entertainment
8.6Crew
Airline reviews

Connecting flight is on time and boarding was a breeze!

10.0 ExcellentGabriel, Sep 2025DEN - SMF
Read more Southwest reviews

Connecting flight is on time and boarding was a breeze!

Very smooth checking in our luggage with a super pleasant SW agent. I enjoyed a fun entertaining movie.

First time traveling on Southwest since bag fees were implemented. Usual good service. Just more expensive now.

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.

The internet service I paid for didn’t work at all and the flight crew was not very friendly.

Subject: Formal Complaint: Discriminatory and Unprofessional Conduct – Request for Immediate Action & Compensation Dear [Airline Customer Relations Team], I am writing to file a formal complaint regarding my recent travel experience with [Airline], which was by far the worst I have ever encountered. What occurred was not only unprofessional, but in several instances discriminatory, unsafe, and unacceptable. On the first leg of my trip, I arrived only four minutes past check-in. Instead of making any attempt to resolve the matter, your representative flatly denied me boarding and made me wait while she attended to passengers who arrived after me. By the time a manager intervened, it was too late to board, costing me time, money, and unnecessary frustration. The second leg of my trip (Chicago–San Francisco) raised even more serious concerns. From the outset, it was apparent that the staff—particularly two attendants—prioritized Caucasian passengers while dismissing African American and minority passengers. • When a Caucasian passenger in the exit row refused to comply with federal safety requirements, I, as a first responder, immediately offered to switch seats and assume the responsibility. My offer was blatantly ignored, and instead, a Caucasian passenger seated further up was chosen. This was discriminatory and deeply insulting, especially as I was actively de-escalating the situation that could have delayed the flight further. • During a lengthy tarmac delay of over 90 minutes, passengers were given conflicting and unreasonable instructions that created unnecessary distress and tension. • Throughout the flight, a visibly intoxicated passenger directly in front of me was disruptive, rude to others, failed to comply with seatbelt and electronic device rules, and yet faced no enforcement from the crew. In stark contrast, I was singled out for repeated compliance checks even though I was following every rule. This unequal treatment was so obvious that multiple passengers around me spoke up in my defense. This pattern of behavior demonstrated a clear lack of professionalism, disregard for passenger safety, and discriminatory treatment. I expect far better from an airline of your stature. As a paying customer subjected to this unacceptable treatment, I am formally requesting: 1. A full investigation into the conduct of the staff on both flights. 2. A written apology acknowledging the discriminatory and unprofessional behavior I endured. 3. Appropriate compensation for the distress, inconvenience, and mishandling of my travel. If this matter is not addressed promptly and thoroughly, I will have no choice but to escalate my complaint further, including filing with the U.S. Department of Transportation and sharing my experience through other channels. I trust [Airline] will take this complaint seriously and provide a timely resolution.

Check in was quick and easy during early hours. Flight was on time, and customer services was a plus.

The flight was comfortable with the exit row and great service

Plane was crowded and even when we hit altitude, the plane was hot, not enough air flow.

1. when we went to check in, our 2 first class seats had been CANCELED and the flight was sold out. This was done without our prior knowledge. It was all we could do to restore one first class seat for my wife and I flew economy. 2, Our flight home was scheduled to leave at 10:30 pm. Due to tsunami warnings, the roads were closed and our flight status was uncertain as to whether it would leave as scheduled. It was announced that it would now leave at 11:20 pm and the roads were now open since the tsunami had come and gone. We made a mad dash to the airport and checked in. Delays were announced at 12:30 pm, 1:30 am, 2:30 am and at 3:30 am it was canceled. Since this was a flight due to natural (tsunami) causes, there was no compensation. We were told to return at 1:00 pm the next day and our baggage would be kept on the plane since the same plane was going to leave at 1:00 pm. We had to return to our hotel for the rest of the night. The same plane did not leave at 1:00 pm and our baggage was gone! All in all, it was a miserable performance by UA. Information was hard to obtain and no one knew what was going on and what was going to happen. Hundreds of passengers slept on the floor, chairs, etc. No food and no water was made available to the passengers. It was a situation where UA could care less what was going on. As a one million mile flyer, I had not experienced anything like this before and it was hugely disappointing!

Boarded plane and then delayed 1.5 hours while on the plane

Horrific. They missed my connecting flight to San Diego. I didn’t get there until Monday at 9am when I had a mandatory court settlement conference scheduled at 6am since we had parties on the east coast. This caused many issues. All because United apparently forgot to hold the doors open until my flight landed that only had a 10 minute delay. This was the last flight to Southern California. So I couldn’t even rent a car to finish the trip. United cannot be trusted when traveling on specific days and times since weather didn’t have anything to do with the delays.

My flight was delayed a very short period of time but they did not hold my connecting flight to San Diego, also through United. So they closed the doors before we got off our plane. They would only have to help the door open for another five to ten minutes. So I missed a court deadline for a manditory mediation settlement conference for my client. I had to get an associate to be there in person and be on the phone with him relaying what he needs to do the entire time. The court was very upset with me and so was my client. United cannot be trusted.

We were given vouchers we couldn’t use with a 5.5 hour delay

The flight crew was rude. We were in first class and no one even offered water until an hour after we were in the air. Horrible experience

Great. Quick and quiet and east. The breakfast choices were a welcome surprise!

The stewardess hit me with the food kart twice on the head and didn't say I'm sorry once. The same stewardess gave me a warm Apple Juice with No ice. The Flight was delayed for Departure 6 times, starting from 2:36pm, finally taking off 7:50pm. I was late picking up my child from the sitter by 3 hours.

Did not get the seat I selected and paid for.

My flight was delayed for several hours. Sitting at gate 16 for several hours, I got a text from Kayak the gate changed to 9 before it was announced. Very bad communication at each gate from American Airlines employees. I received 10 notifications of delay from Kayak. My vacation started off horrible! I will write to American Airlines corporate office also.

Delayed flight that lead to a missed connection and a 5-hour trip became a 12-hour flight 🙄

There is no room, no gluten free options, or any free internet/entertainment. You have to bring your own tablet or smartphone because there are no screens.

Amazing food, great staff, with one noticable detail missing ...but no seat entertainment in any of aircraft ...I am not a fan

Boarding gate in Honolulu was staffed with a great clerk with a soothing voice despite the flight delay of over an hour. Flight attendants in the plane were all grumpy, not pleasant looking bunch. Their sour attitude showed throughout the flight. Inly able to get a select few movies started. Most of the movie links in the “free entertainment” did not work.

This was a horrible experience. For a first class experience, my chair was held together by 3M tape - and I have a photo. The crew weren’t very attentive, somewhat dismissive and forgot my drink and snack, the chair reclined about 3 inches on a 6-hour cross country flight. I was also not informed that there was no lounge available in Newark airport because of renovations, so all around this was one of the worst experiences and I would actively avoid both American and Alaska Air going forward.

My luggage didn’t arrive at LAX, so that wasn’t a good experience.

I was never aware that I had to pay $100 per luggage to them on the plane that are simply carry-ons. This is discriminatory and I’m going to be alerting my entire family and friends and my Instagram following up over 75,000 of this issue and misunderstanding, including mismanaging.

Cancelled my flight last minute and did not help me rebook. It was a horrible experience.

Late departure by 1:45min. No explanation why. During boarding inconsistent policing of their baggage rules. Before takeoff and lamdimg strange obsession with window shade and armrest positions. Don't know why they care. 15 min tarmac delay on arrival, they blamed airport congestion but we were the o lh flight waiting, it was clear it was due to poor staff planning (only one ground crew to receive airplanes and multiple arrivals) Got there but was rrally lame the whole trip.

Boarding was a breeze, however, two of the flights that I boarded with Spirit did not have Wi-Fi available.

Very good. Nothing more or less than expected. No complaints.

My experience with the spirit as a first time it was OK, but the seats need a little cushion, the problem I had the most impacted me was when checking in the scales were so off and wrong. It will tell that you would have more weight, which was not true. The scale was say that it had Thirty Eight Pounds, when get in the labels when we send the luggage into the band. It says that it was overweight. I really really dislike that because the scales are not accurate. If I use Spirit and I have that issue again. That will be my last time flying with the spirit, even though I like so much to service the planes, and everything else

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

I think Frontier was very good at communication. Their app worked very well. Loading was great and the flight was nice and easy.

This airline sucks. They offer low rates then charge you for everything, the app does not work well, the seats are the most uncomfortable. Maintenance issues on the flight, and you still have to sit through their credit card commercials. People are nice enough but does not make up for overall poor experience.

Great for the price. No wifi or entertainment, but gate agents and crew were fantastic and we boarded quickly and left on time.

Decent clean onboard experience. Okay discount airline experience. Unfortunately, any customer service interactions are difficult and unhelpful. There is no service. Also, a premium seat only gets you premium boarding if you line up first. Once they start general boarding you must go to the back of the line. Not very premium

The crew was mostly okay. The flight attendant who answered our questions was curt and unhelpful unfortunately. He seemed upset and I understand having off days.

Very bad! No good service delayed my second connection flight

They canceled flight. Hard to believe there was even a plane incoming for us to get on

Cancelled flight after I arrived at airport after 75 min drive and parking. Next flight was 4 days in the future. Had to scramble and buy a much more expensive flight on another carrier.

I liked the turn-style feature at gate 209B at LAX. Very efficient process. The gate staff also made several, clearly directed announcements so I felt very informed.

Plane was down graded and I lost my uncharged exit row with more leg room. No mention or offer of refund from podium. Flight attendant was nice to explain this happens often and that I could request a refund via online form submission. I did this and have heard nothing back.

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