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IAD - ONT

$145 Find cheap flights from Washington Dulles Airport 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 Dulles Intl to Ontario departing on 7/2. 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
Wed 7/10
Wed 7/17

Search 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
In the last 7 days travelers have searched 42,898,604 times on KAYAK, and here is why:

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Filter your dealsChoose cabin class, free Wi-Fi and more.

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Cheap flight deals from Dulles Intl to Ontario (IAD-ONT)

Here are some of the best deals found on KAYAK recently from the most popular airlines for round-trip flights from Dulles Intl 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 and deals for you by selecting your travel dates.
Choose your dates
6:00 am - 10:13 amIAD-ONT
7h 13m1 stop
1:21 pm - 11:50 pmONT-IAD
7h 29m1 stop
$290Delta
Find Deal
Wed, Aug 7 - Thu, Aug 15
6:00 am - 10:13 amIAD-ONT
7h 13m1 stop
6:59 pm - 10:48 amONT-IAD
12h 49m2 stops
$295Delta
Find Deal
Sat, Aug 24 - Mon, Aug 26
6:00 am - 10:13 amIAD-ONT
7h 13m1 stop
5:00 pm - 9:16 amONT-IAD
13h 16m2 stops
$299Delta
Find Deal
Wed, Aug 7 - Wed, Aug 14
7:15 am - 12:18 pmIAD-ONT
8h 03m1 stop
1:21 pm - 11:50 pmONT-IAD
7h 29m1 stop
$304Delta
Find Deal
Wed, Jul 3 - Thu, Jul 11
6:55 am - 1:46 pmIAD-ONT
9h 51m1 stop
10:51 am - 11:10 pmONT-IAD
9h 19m1 stop
$324American Airlines
Find Deal
Sun, Sep 8 - Thu, Sep 12
9:14 am - 6:24 pmIAD-ONT
12h 10m2 stops
8:10 am - 12:18 amONT-IAD
13h 08m2 stops
$344American Airlines
Find Deal
Sat, Aug 24 - Mon, Aug 26
7:01 am - 12:15 pmIAD-ONT
8h 14m1 stop
1:45 pm - 12:49 amONT-IAD
8h 04m1 stop
$347United Airlines
Find Deal
Wed, Jul 17 - Wed, Jul 24
7:01 am - 12:15 pmIAD-ONT
8h 14m1 stop
1:45 pm - 12:49 amONT-IAD
8h 04m1 stop
$351United Airlines
Find Deal
Tue, Jul 16 - Wed, Jul 31
7:02 am - 3:29 pmIAD-ONT
11h 27m1 stop
8:20 pm - 7:35 amONT-IAD
8h 15m1 stop
$460Alaska Airlines
Find Deal
Tue, Jul 9 - Tue, Jul 16
7:02 am - 3:29 pmIAD-ONT
11h 27m1 stop
4:24 pm - 7:35 amONT-IAD
12h 11m1 stop
$500Alaska Airlines
Find Deal
Tue, Aug 6 - Mon, Aug 12

Flights from Dulles Intl to Ontario - Travel Insights & Trends

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

What’s the cheapest day of the week to fly from Washington Dulles Airport to Ontario?

The average price of all flights from Washington, D.C. Dulles Intl Airport to Ontario clicked on KAYAK for each day over the last 12 months.
For Washington Dulles Airport to Ontario, Tuesday is the cheapest day to fly on average and Monday is the most expensive. Flying from Ontario back to Washington Dulles Airport, the best deals are generally found on Tuesday, with Sunday being the most expensive.

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

To calculate monthly average prices, KAYAK takes all prices for each month over the last year for flights from Washington, D.C. Dulles Intl Airport 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. Dulles Intl Airport to Ontario is January, where tickets cost $258 on average. On the other hand, the most expensive months are July and June, where the average cost of tickets is $433 and $427 respectively.

How far in advance should I book a flight from Washington, D.C. Dulles Intl Airport to Ontario?

To calculate daily average prices, KAYAK takes all prices for each day before departure over the last year for flights from Washington, D.C. Dulles Intl Airport to Ontario, removes the top 0.1% to account for outliers, and then takes the average of all the values for each month.
To get a below average price on the flight from Washington, D.C. Dulles Intl Airport to Ontario, you should book around 3 days before departure. For the absolute cheapest price, our data suggests you should book 40 days before departure.

Which airlines provide the cheapest flights from Washington Dulles Airport to Ontario?

The cheapest price for the route for each airline clicked by KAYAK users in the last 72 hours.
In the past 3 days, the cheapest one-way tickets to Ontario from Washington Dulles Airport were found on Delta ($145) and American Airlines ($150), and the lowest round-trip tickets were found on Delta ($290) and American Airlines ($324).

Good to know

Low season

February

High season

August

Cheapest flight

$145
Best time to beat the crowds with an average 35% drop in price.
Most popular time to fly and prices are also 6% lower on average.
Flight from Washington Dulles Airport to Ontario

When to book flights from Dulles Intl to Ontario

Are your dates flexible? Find out the best times to travel from Dulles Intl 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 Washington Dulles Airport to Ontario flights

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

    In the last 3 days, the lowest price for a flight from Washington, D.C. Dulles Intl Airport to Ontario was $145 for a one-way ticket and $290 for a round-trip.

  • Do I need a passport to fly between Washington Dulles Airport and Ontario?

    No, a passport isn't needed to fly from Washington Dulles Airport to Ontario. However, local authorities might ask for an official ID.

  • Which airports will I be using when flying from Washington Dulles Airport to Ontario?

    Washington Dulles Airport and Ontario are both served by 1 main airport. You will leave Washington Dulles Airport from Washington, D.C. Dulles Intl and will be arriving at Ontario.

  • Which aircraft models fly most regularly from Washington Dulles Airport to Ontario?

    We unfortunately don’t have that data for this specific route.

  • Which airline alliances offer flights from Washington Dulles Airport to Ontario?

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

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

    The two airlines most popular with KAYAK users for flights from Washington, D.C. to Ontario are Delta and United Airlines. With an average price for the route of $353 and an overall rating of 8.0, Delta is the most popular choice. United Airlines is also a great choice for the route, with an average price of $505 and an overall rating of 7.4.

  • How does KAYAK find such low prices on flights from Washington Dulles Airport 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 Dulles Airport to Ontario.

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

    KAYAK’s flight Price Forecast tool uses historical data to determine whether the price for a flight to Ontario from Washington Dulles Airport 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 Dulles Airport 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 Dulles Airport with another airline. Booking your flights between Washington Dulles Airport and ONT can sometimes prove cheaper using this method.

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

See more FAQs

Top 3 airlines serving from Dulles Intl 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 Dulles Intl 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
DeltaOverall score based on 10295 reviews
8.6Crew
7.9Comfort
8.2Boarding
8.0Entertainment
7.4Food
Airline reviews

It was good until there was a 3 hour delay because there was not any pilots to fly the plane.

2.0 MediocreFelipe, Jun 2024DTW - SAN
Read more about Delta reviews

It was good until there was a 3 hour delay because there was not any pilots to fly the plane.

Had to change aircraft due to a faulty door. Surprisingly it only caused about an hour and a half of delay. Delta handled this situation as well as can be expected.

Your crew could maybe answer the call bell at least one of the times I pressed it. I pressed it first time with 2.5 hours left in our flight bc my partner was hungry and wanted a sandwich. We finally got the sandwich with 40 mins left in the flight.

The Flight crew didn’t serve us until about 1.5 hours into the flight because of turbulence but after it ended it was fine to move around. They served us water only and snacks and then NEVER, NOT ONE TIME came through to collect trash until right before landing about 1.5 hours later. There was absolutely no need for that. They crew was just standing around talking and visiting with each other and really never tried to see if we might want something besides water or even try to come pick up trash. This is VERY unusual for a Delta flight but it was not what I would have expected for a 4 hour flight.

There was a loud squeaky sound the whole time we were flying.

Had a broken tray in business class. Crew just shrugged it off.

I didn’t like that I could not select my seat and was assigned a seat when I checked in at LAX

Great experience overall. Check in at Austin was congested as they only have about 6 check in kiosks, one was broken, and there was a lot of Spring Break travelers.

Bag drop off was slow and annoying. Only 2 agents at the entire delta desk, and no one directing traffic for what line to be in, many confused people slowed down the process. Boarding was fine. Seats in Delta comfort plus were fine. Snacks were great! Definitely a bonus. The entertainment system was awful — old, slow, not responsive, and completely unable to play games due to some kind of error. But on the other hand, thank you to Delta for the free WiFi. That made it better.

Everything was very good other than I had selected a specific seat when I booked the flight and they changed it once I checked-in the day before my flight. I was still in first class but lost my aisle seat for a window seat. Being tall, the aisle offers more comfort so I always select an aisle seat.

We ended up with seats in the very back. So they did not recline. Have no idea why, we reserved and checked in very early. The isles were very narrow and the seats had very little leg room. But they did give us water, and a snack.

Should have video screens Plane audio was poor and without wired connection hard to understand crew. Should serve more than just cups of water and pretzels on six hour flight. Did not see crew rest of flight. Fix charging sockets to retain charging blocks.

they made me check my carryon. There was space in the overhead bins.

The plane was delayed 2 hours. The wifi did not work. The seat in first class was not comfortable because the bottom felt like it lost all of its padding. And I did not like when the flight attendant made me wait at my seat to use the bathroom and didn't tell me why. If there were too many people using the 1st Class bathroom, she should have told me to go in the back, coach bathrooms. I guess I have to feel fortunate that they found 2 local pilots to still fly the plane tonight after the original pilots ended up at an airport 60 miles away due to high winds.

The crew were really great, but the 4 hour delay in small chunks was the worst.

Airline did not explain reasons why flight was delayed two hours. Explanations were badly needed and rarely provided. Problem seemed to clearly be the airline’s fault and not the fault of the weather or airport.

Just a crappy airline. The same every time. You feel you are a cow on a farm. You are being being whipped and pulled.

Wasn’t very crowded. Seamless processes. No issues traveling with two little kids.

My interaction with the flight attendent Eve was horrible. I was seated in 3F and was blown away watching her repeatedly skip me as she took other customer orders for lunch...she took the customer next to me but skipped me, then took everyone's order around me (in front of and behind me) . After she had taken every customer's orders to include those behind me, she came to me and said we are out of everything except one last item. I was mortified, in that, I am a 1k flyer, had pre-ordered AND as an African American could only assume why she repeatedly skipped me...mortified. no words

The Flight was good, pilot seemed very skillful. My wheel chair sister who could barely walk was allotted the second last seat in the aircraft, with great difficulty she managed to reach on her seat, as she required attendance we were given separate seat, even on request no one cared, so much so there were single passengers who were given twin seats. May not be taken as complaint but a reminder to the checkin staff to keep in mind in future the allottment of wheel chair passengers seats.

This is by far the worst experience I have had with American Airlines. The start of this trip was a complete disaster. I purposely planned my trip so that I would weather any delays so that I could make very important meeting at the Pentagon. My flight was cancelled because of maintenance and I was put on the first flight the next day but I was late to the meeting. After a long week at the Pentagon I just wanted to go home and my flight home which was early in the day was delayed. Eventually the flight was delayed until the next day. I was not authorized a hotel room because DCA was my point of origin. So I paid for a hotel out of pocket. The flight this morning was boarded then deplaned because the aircraft was hot. The flow of information was not happening in DCA and made it worse when the news was bad. I am going to take a break from American for my next few military flights. Hopefully whatever has been going on with American Airlines will be resolved.

AA1537 the AC was not working properly. It was very hot and uncomfortable.

Everything was great except for the wifi was junk. Crew was super friendly and helpful

Overall the flights pretty good. The snacks we’re good and they were plenty of them. Both boarding and deplaning went quickly.

Delayed abs delayed Gate crew giving poor info - we are definitely leaving at —- Ultimately to cancel flight after 4+ hours of delays Just cancel it earlier

The flight was scheduled to depart DCA at 12:30 pm but was delayed twice on the ground so that we were finally scheduled to depart at around 4:00 pm. Once we boarded, it was announced that takeoff would be delayed again to fix a hydraulic problem which delayed our eventual takeoff until around 5:00 pm. Once we departed, it was a smooth flight back to ORD. We did not get any explanation about what caused the original significant delay. In my experience, this happens frequently with AA.

Lots of weather delays that were poorly communicated and managed. I get there are weather delays but they didn’t make it clear what was happening or comfortable on the plane

Everything was on time; the flight attendants and the gate personnel were very pleasant and helpful.

Our second leg to Jackson WY was unable to land due to weather. We were flown back to Dallas after stopping in SLC. We were given hotel rooms and vouchers. We were told that we would be back on the same plane in the morning. Instead we were given a different flight with different seats. Not a good experience. No one knew what was going on.

Perfect flight. On time departure and early arrival. Smooth flight.

Book cheap flights from Washington, D.C. to Ontario

Recent one-way flight deals

 
Only flying one-way? Below are some of the best one-way flight deals from Washington, D.C. to Ontario found on KAYAK in the last 72 hours.
7/2Tue
1 stopDelta
8h 03mIAD-ONT
$145
8/13Tue
2 stopsAmerican Airlines
12h 10mIAD-ONT
$150
7/2Tue
1 stopDelta
8h 03mIAD-ONT
$159
7/2Tue
2 stopsAmerican Airlines
13h 51mIAD-ONT
$194
7/4Thu
1 stopUnited Airlines
7h 38mIAD-ONT
$195
7/10Wed
1 stopUnited Airlines
8h 14mIAD-ONT
$229
9/4Wed
2 stopsAlaska Airlines
18h 15mIAD-ONT
$242
8/18Sun
2 stopsAlaska Airlines
18h 38mIAD-ONT
$248
9/7Sat
2 stopsAvianca
22h 25mIAD-ONT
$628
8/11Sun
2 stopsAvianca
22h 30mIAD-ONT
$656

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Last minute flights from Dulles Intl to Ontario

Last minute flight, train and bus deals

 
These last-minute flight deals are the cheapest flights found on KAYAK in the last 72 hours for flights from Washington, D.C. to Ontario that are departing in the next 10 days.
6/12Wed
multi-stopDelta
7h 42mIAD-ONT
6/18Tue
multi-stopDelta
7h 45mONT-IAD
$584
6/12Wed
multi-stopDelta
13h 17mIAD-ONT
6/18Tue
multi-stopDelta
7h 34mONT-IAD
$589
6/12Wed
multi-stopAmerican Airlines
9h 54mIAD-ONT
6/18Tue
multi-stopAmerican Airlines
10h 45mONT-IAD
$594
6/12Wed
multi-stopAlaska Airlines
11h 26mIAD-ONT
6/14Fri
multi-stopAlaska Airlines
10h 59mONT-IAD
$624
6/12Wed
multi-stopAmerican Airlines
11h 48mIAD-ONT
6/20Thu
multi-stopAmerican Airlines
10h 32mONT-IAD
$634
6/15Sat
multi-stopAlaska Airlines
11h 20mIAD-ONT
6/30Sun
multi-stopAlaska Airlines
22h 30mONT-IAD
$636
6/15Sat
multi-stopUnited Airlines
11h 04mIAD-ONT
6/22Sat
multi-stopUnited Airlines
8h 20mONT-IAD
$684
6/11Tue
multi-stopUnited Airlines
8h 45mIAD-ONT
6/14Fri
multi-stopUnited Airlines
8h 00mONT-IAD
$724
6/15Sat
multi-stopAvianca
18h 45mIAD-ONT
6/23Sun
multi-stopAvianca
22h 45mONT-IAD
$1,694
6/15Sat
multi-stopAvianca
18h 45mIAD-ONT
6/23Sun
multi-stopAvianca
22h 45mONT-IAD
$1,712

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Washington Dulles Airport - Ontario Flights

Departure:

Washington Dulles Airport (IAD)United States

Destination:

Ontario (ONT)United States

Return flight deals:

Ontario - Washington Dulles Airport

Cabin classes: