WAS - ONT

$65 Find Cheap Flights from Washington, D.C. 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 from Washington, D.C. to Ontario departing on 2/27. 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, 0 bags

KAYAK searches hundreds of travel sites at once for deals on flights to Ontario

 
These are the airlines KAYAK users have selected most often from within our search results in flight searches from Washington, D.C. to Ontario, as well as popular online travel agencies
These are the airlines KAYAK users have selected most often from within our search results in flight searches from Washington, D.C. to Ontario, as well as popular online travel agencies
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Everything you should know

Cheapest round-trip
$142
Overall average: $336
Frontier
Sat 1/24Fri 1/30
DCA - ONT • 1 stop
Cheapest non-stop
$611
Southwest
Mon 12/22Fri 12/26
BWI - ONT • Non-stop
Top airlines
Frontier
Cheapest • from $149 (round-trip)
Southwest
Best reviews • 8.0 score
Airline reviews
Airline reviews
+1
+1
Airline reviews
Airline reviews
+1
Top routes
BWI-ONT
Cheapest
BWI-ONT
Most popular
Insights
Insights
Insights
Insights
When to travel
April
Cheapest • 14% price drop
December
Most popular
Good to know
Good to know
+1
+1
Good to know
Good to know
+1
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We hope you love your trip to Ontario!
Flight Deals
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Flight Deals

Cheap Flights from Washington, D.C. to Ontario (WAS-ONT)

 
Here are some of the best deals found on KAYAK recently from the most popular airlines for round-trip flights from Washington, D.C. 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 Washington, D.C. to Ontario

Sat, Jan 24 - Fri, Jan 30
Frontier Logo
2:00 pm - 11:24 pmDCA-ONT
12h 24m1 stop
Frontier Logo
6:20 am - 4:59 pmONT-DCA
7h 39m1 stop
$142Frontier
Find Deal
Sat, Jan 24 - Mon, Jan 26
Frontier Logo
2:00 pm - 11:24 pmDCA-ONT
12h 24m1 stop
Frontier Logo
6:20 am - 4:59 pmONT-DCA
7h 39m1 stop
$148Frontier
Find Deal
Sun, Feb 1 - Thu, Feb 26
Frontier Logo
10:50 am - 4:26 pmIAD-ONT
8h 36m1 stop
Frontier Logo
6:56 pm - 9:54 amONT-IAD
11h 58m1 stop
$148Frontier
Find Deal
Sat, Jan 24 - Fri, Jan 30
Frontier Logo
2:00 pm - 11:24 pmDCA-ONT
12h 24m1 stop
Frontier Logo
6:20 am - 9:59 pmONT-DCA
12h 39m1 stop
$149Frontier
Find Deal
Wed, Jan 28 - Wed, Feb 11
American Airlines Logo
7:00 am - 12:03 pmDCA-ONT
8h 03m1 stop
American Airlines Logo
9:59 am - 8:15 pmONT-DCA
7h 16m1 stop
$169American Airlines
Find Deal
Wed, Jan 28 - Wed, Feb 11
American Airlines Logo
5:26 pm - 10:48 pmIAD-ONT
8h 22m1 stop
American Airlines Logo
10:58 am - 9:17 pmONT-IAD
7h 19m1 stop
$169American Airlines
Find Deal
Wed, Jan 28 - Wed, Feb 11
American Airlines Logo
11:34 am - 6:20 pmIAD-ONT
9h 46m2 stops
American Airlines Logo
10:58 am - 9:17 pmONT-IAD
7h 19m1 stop
$174American Airlines
Find Deal
Wed, Jan 21 - Tue, Jan 27
Southwest Logo
9:05 am - 5:10 pmIAD-ONT
11h 05m2 stops
Southwest Logo
5:55 am - 4:50 pmONT-IAD
7h 55m1 stop
$189Southwest
Find Deal
Wed, Jan 7 - Sat, Jan 10
Southwest Logo
4:30 pm - 9:05 pmIAD-ONT
7h 35m1 stop
Southwest Logo
5:50 am - 2:55 pmONT-IAD
6h 05m1 stop
$192Southwest
Find Deal
Wed, Jan 7 - Wed, Jan 7
Southwest Logo
7:55 am - 1:50 pmBWI-ONT
8h 55m1 stop
Southwest Logo
5:45 pm - 5:45 amONT-BWI
9h 00m1 stop
$199Southwest
Find Deal
Booking Insights

KAYAK's insights & trends for Washington, D.C. to Ontario flights

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

What is the cheapest Washington, D.C. to Ontario flight route?

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

The cheapest return flight from Washington, D.C. to Ontario costs $841 on the route between Baltimore (BWI) and Ontario (ONT). It is also the most popular route.

What’s the cheapest day of the week to fly from Washington, D.C. to Ontario?

The average price of all round-trip flights from Washington, D.C. to Ontario clicked on KAYAK for each day over the last 12 months.

If you are looking for a flight deal from Washington, D.C. to Ontario, look for departures on Thursdays and avoid leaving on a Saturday, as it's usually the priciest day. When flying back from Ontario, Thursday is the cheapest day to fly and Monday is the most expensive.

What is the cheapest month to fly from Washington, D.C. to Ontario?

To calculate monthly average prices, KAYAK takes all prices for each month over the last year for round-trip flights from Washington, D.C. to Ontario, 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 Washington, D.C. to Ontario is April, where tickets cost $326 (return) on average. On the other hand, the most expensive months are November and December, where the average cost of round-trip tickets is $462 and $428 respectively.

Can I save money by flying with a layover from Washington, D.C. to Ontario?

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 $379, prices are generally cheapest when you fly direct.

Good to know

Low seasonFebruary
Cheapest flight$60
Best time to beat the crowds with an average 12% drop in price.
Most popular time to fly with an average 12% increase in price.
Flight from Washington Dulles Airport to Ontario

When to book flights from Washington, D.C. to Ontario

Are your dates flexible? Find out the best times to travel from Washington, D.C. to Ontario based on our flight data from the last year. Discover the cheapest month and even day to fly.
Estimated round-trip price
KAYAK looks at all historical flight data for each date to provide a predicted price for one-way trips or round-trips with a duration up to 40 days. While we try to provide actual minimum prices for each date, some prices are predictions and actual prices may differ.

FAQs for booking flights from Washington, D.C. to Ontario

  • What is the cheapest flight from Washington, D.C. to Ontario?

    In the last 3 days, the lowest price for a flight from Washington, D.C. to Ontario was $60 for a one-way ticket and $148 for a round-trip.

  • Do I need a passport to fly between Washington, D.C. and Ontario?

    A passport is not required to fly from Washington, D.C. to Ontario.

  • Which airports will I be using when flying from Washington, D.C. to Ontario?

    Washington, D.C. is served by 2 major airports and there is only 1 main airport in Ontario. You will leave Washington, D.C. from one of these airports: Washington, D.C. Reagan-National or Washington, D.C. Dulles Intl. You will be arriving at Ontario.

  • Which airlines offer Wi-Fi service onboard planes from Washington, D.C. to Ontario?

    Hawaiian Airlines, and Alaska Airlines offer inflight Wi-Fi service on the Washington, D.C. to Ontario flight route.

  • Which aircraft models fly most regularly from Washington, D.C. to Ontario?

    The Boeing 737 MAX 8 is the aircraft model that flies most regularly on the Washington, D.C. to Ontario flight route.

  • Which airline alliances offer flights from Washington, D.C. to Ontario?

    SkyTeam, Star Alliance, and oneworld are the airline alliances operating flights between Washington, D.C. and Ontario, with SkyTeam being the most commonly used for this route.

  • On which days can I fly direct from Washington, D.C. to Ontario?

    You can catch a nonstop flight from Washington, D.C. to Ontario on on Monday, Tuesday, Thursday, Friday, Saturday, and Sunday.

  • Which is the best airline for flights from Washington, D.C. to Ontario, Southwest or Delta?

    The two airlines most popular with KAYAK users for flights from Washington, D.C. to Ontario are Southwest and Delta. With an average price for the route of $477 and an overall rating of 8.0, Southwest is the most popular choice. Delta is also a great choice for the route, with an average price of $356 and an overall rating of 7.9.

  • How does KAYAK find such low prices on flights from Washington, D.C. 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 Washington, D.C. to Ontario.

  • How does KAYAK's flight Price Forecast tool help me choose the right time to buy my flight ticket from Washington, D.C. to Ontario?

    KAYAK’s flight Price Forecast tool uses historical data to determine whether the price for a flight to Ontario from Washington, D.C. 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 Washington, D.C. 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 Washington, D.C. with another airline.

  • What is KAYAK's "flexible dates" feature and why should I care when looking for a flight from Washington, D.C. 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 Washington, D.C. up to 3 days before/after your preferred dates. You can then pick the flights that suit you best.

KAYAK’s top tips for finding a cheap flight from Washington, D.C. to Ontario

  • Looking for a cheap flight? 25% of our users found flights on this route for $306 or less one-way.

Reviews of the top 5 airlines serving from Washington, D.C. to Ontario

 
See real verified KAYAK customer reviews for airlines flying from Washington, D.C. to Ontario. 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 Washington, D.C. 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
SouthwestOverall score based on 4253 reviews
8.1Boarding
8.0Comfort
7.0Food
7.5Entertainment
8.6Crew
Airline reviews

No delays and arrived to destination 30 min early. Staff was super friendly.

10.0 ExcellentIlevba, Nov 2025DCA - DAL
Read more Southwest reviews

No delays and arrived to destination 30 min early. Staff was super friendly.

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

Ever since Southwest starting charging for bags, passengers don't want to pay to check their bags, so the gate agents have to beg people to check their roller bags now because there's "not enough space". This was a terrible business move by Southwest.

Delays delays delays. Late taking off, late landing, wait for a gate, etc.

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.

Staff were friendly and happy. Delta could make sure passengers that don't have the app know of changes. Without Kayak I would not have known about the change of gate or the delay. Kayak was faster to notify me.

They changed planes and the new plane couldn’t carry enough fuel to fly across the country so we had to stop in Kansas City to refuel. Flight was delayed .

Flight was too crowded and seats are too small, especially since passengrs are getting larger. Having a middle seat is ALWAYS tough! Woman on my left was large & kept creeping in to my space. Flight personnel were great! Have more savory rather than sweet snacks please.

The crew took good care of us. The flight from ATL to SFO is a longer one, and there were multiple beverage offerings. I like the 757's that Delta uses. Good airplane that is comfortable. I do wish Delta would separate Priority boarding from the better seats. I would gladly take a smaller seat in an open row than be jammed into Comfort just to get priority boarding, just to make sure I don't have to check a bag.

Gate agent rushed to fill hot jetway with crowd so it took over 12 minutes to go from gate to plane. Just like a discount airline Pooly prepared cabin and third time that claim of rough air prevented any cabin service. Friends on a Southwest flight at similar time had service.

I was uncomfortably cold on the plane. Other than that it was uneventful and therefore as enjoyable as a plane ride can be.

Food was surprisingly good but the WiFi was not great

My flight was extremely cold. I had a jacket and a cover was left in each seat. The cover was extremely thin and I have a disability, fibromyalgia and arthrithis and AC air is the worst. I closed my vent and my husbands vent and it still was frigid. I asked the attendant if I could get another cover and she quickly almost dismissively and totally unconcerned stating, (I quote) (one per chair) and walked off so quickly that I didn't get a chance to explain to her that I literally have adisability. I didnt want to make a seen so I set on that flight for over 5 hours in pain, joints locking up and extremely uncomfortable. When my fibromyalgia flares up my joints not only ache but they will lock up also and it takes me days to get back to my regular self even though I take medication for it. I felt like it would not have hurt anyone at all for her to just give me an extra cover because I'm sure they have all types of medical issues in people that fly every day.

Not a "Delta" issue, but a JFK issue: We booked a connecting flight with 3 1/2 hours between to clearn immigration and customs. Our inbound flight (BCN to JFK) was on the taxiway 45 minutes which ate into our layover time. Immigtration was insanely quick with the CBP MPC app; however, clearing TSA (again, after we were ALREADY cleared in Spain on the inbound international flight) took over 95 minutes. This left us with 10 minutes before boarding the connecting flight (JFK to SAN) to walk to the far end of Terminal 4 and try to find food. We didn't find any food that could promise to serve us in under 10 minutes so we boarded the Delta flight after coming off a plance and an 8-hour flight knowing that we wouldn't be served any food on the next 5 1/2 hour flight. I feel like Delta needs to put pressure on the JFK TSA to open more screening stations (by our count, we saw only 5 scanners open and a line of - as we said - over 90 minutes. The insult is that we WERE ALREADY SCREENED through TSA, but as you come off one flight into the USA, you have to go through the whole process again. It seems like if you have a connecting flight, there should be a way to pass through immigration and customs without needing to return through TSA.

There are 4 flights in consecutive gates with about the same departure time. Two flights were boarding at the same time. One was delayed or boarding would be happening at the same time. I am not sure what Delta and LAX need to do to have a better layout at the end of Terminal 2

Starlink wifi on the Embraer E175 is an excellent experience. I was able to connect and work from IAD all the way to approach into BTV.

7 hours delayed due to operational issues on United’s end. Basically laziness.

Short flight but an "eager to help" crew made the journey more enjoyable!

During booking, I kept trying submitting my payment from the Mexican website and it didn't work. After I had the idea to change it to the Canadian website, it worked but I had to be charged the equivalent of 50 CAD more. I received the clear instruction that I would only be able to check-in at the airport and that it was impossible to select a seat 24 hours before departure, that I had to pay 144 CAD to do so, although not only was I able to check-in 24 hours before departure, but I could have selected my seats for free then. All in all, I almost threw $200 out the window due to misleading information. Besides, the app kept crashing, the information to get to the gate on the app was inaccurate, my gate was switched and I was only informed once in the air (luckily I had noticed the departure pannel), I was not addressed in my language beforehand and even if I tried I was immediately answered in English (which meant the crew understood but didn't want to answer accordingly), there was only one snack & beverage service on my medium haul flight and no beverage service on my short haul flight. To be fair, the planes were comfortable, the crew apart from the language issue was helpful, dynamic and engaging, the plane was clean and the directions were clear and direct. United has a lot of potential to be one of my favourite airlines, but the devil is in the details and a lot of them missed the target.

Better WiFi. I cannot understand that in 2025, United is so behind on a technology that is now a necessity and still painfully unreliable, slow and keeps disconnecting.

Great service on board. Boarding a bit slow due to process. Food was pretty average.

Very small cramped plane for an international flight. Everything else was good, but it was maybe the smallest comfort-wise I've ever been on for longer than 3-4 hours and the trip was 7.5

Flight was delayed 3 hours. No food and drink vouchers was provided. They offered a mini pretzel bag and water .

Staff was rude. Didn’t give water for 2 hours. Worst service

Was on time until within 1 hour of flight-how does that happen? Staff very friendly.

We were told the flight was delayed 5 times, then it was moved to the next day.

The experience with American Airlines was good, although the Philippines Airlines flight was much better (better seats, better food, better entertainment options, overall better). Again, the MIA to LAX flight was fine, but nothing in comparison to the comfort and accommodations of the Philippines Airlines flight from LAX to MNL.

Loved the crew . Absolutely no complaints. Except for luggage lost

Flight delay was communicated before leaving for airport which caused it to be a non-event. Great flight and crew!

Wish some foods provided rather than just biscuit/cookie for flight more than 2 hours

The flight attendant, a black woman with curly hair who sat near Row 21, was wonderful and kind.

We are too tired and frustrated to comment politely at this point

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

It took way too long to diagnose and solve the problem of a broken crew member cabin seat. Though compensation for the volunteer who left the flight was very kind.

We fly American Airlines quite a bit. And we always fly business class when traveling internationally. We were a bit disappointed with the comfort of this particular plane as well as the entertainment options.

Horrible. I would never fly Frontier again. The booking process is tricky at best, but fraudulent in my opinion. Frontier customer service did nothing to rectify my purchase -- I ended up paying more than double what I could have gotten from other airlines and nearly triple what I thought I was buying from Frontier. Their booking practices are unfair to the consumer.

Delayed. Text notifications were slow. Not much information o what was happening. Boarding was slow and confusing. Wasn’t even offered water other flight. Had to ask. No entertainment at all. Felt like.a Greyhound bus.

When I wanted to check in 3 hours prior to boarding time, the employees mentioned “a little over an hour delay” so I waited for an hour then I went to go look for food in the terminal and most people from that flight were in the same area looking for food. Finally I decided after food to check to see if it’s anytime closer and now it’s 2 mins until boarding closes?! What are you kidding me? I didn’t receive anything via sms about boarding now nor via email or on the intercom. I luckily made it through, barely, and then there’s no room for my carry on mind you I’m in the very first row so I had to place my purse in one further row back and my carry on sections down. Not sure who pays for better seats to get your stuff placed all over the plane but that was the worst experience I’ve ever had flying with anyone.

Better than expected. Staff were friendly and nice on both flights.

There was no one at the counter to assist with our check in. The app didn’t work, so I arrived at the airport with time to check in and I couldn’t because no employees were there. When I finally got someone on the phone, it was inside the 60min rule and they said I could no longer check in and they could sell me another ticket. We had to scramble and pay an additional $800 for tickets and THEN AFTER (about 60 min from my original convo with customer service and 10min after original departure time) I had boarded my new flight, there was email saying my original flight from Frontier was delayed and leaving 2hr 50min later, but I STILL wouldn’t have been able to check in. Which means customer service should have been able to see it and let me check in because I was well within my check in time. When I call Frontier, they hang up on me. So their app didn’t work and they employees left and they take zero responsibility or assistance with their “customer service”

Terrible. Flight cancelled with no reasoning and no flights to rebook. Employees were useless and did nothing to help. Did not even know where to retrieve luggage from the cancelled flight. Flyers beware.

No fault of Frontier staff: plane was very late, reached Orlando at 1 am, took a while to get luggage. Weather, gov financial shutdown impact on TSA, air controllers seemed to have multiple flights backed up. Frontier staff seemed to cope as gracefully as possible. It did reassure me that I and my new hip could adapt to travel challenges. Food/entertainment were irrelevant to my trip.

Terrible. The canceled my entire flight when I requested a refund for a trip frontier canceled trip one way.

Boarding was on time and plane departed as scheduled. There are obviously no amenities (food, drink, entertainment) on Frontier, but there also didn't seem to be any issues with luggage space either.

Inbound plane was on time and flight departed on time with no issues while boarding.

Everything you need to know for your flight from Washington, D.C. to Ontario

Information on your arrival and departure airports