Find flights
Deals
Insights
When to book
FAQs & Tips
Airlines

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 6/22. 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
Sat 6/15
Sat 6/22

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 42,211,976 times on KAYAK, and here is why:

Save 21% or moreCompare multiple travel sites with one search.

Track pricesNot ready to book? Create a price alert for when prices drop.

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

Bundle and saveSave money when you bundle your flight + hotel.

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

 
These are the cheapest deals for flights from Dulles Intl to Ontario currently on KAYAK along with options from the most popular airlines KAYAK users selected for this route. While these flights were available on KAYAK in the last 72 hours, prices and availability are subject to change and deals may expire.

Recent round-trip flight deals from Dulles Intl to Ontario

Recommended round-trip deals departing in the coming months from the most popular airlines that fly from Dulles Intl to Ontario.

Recent one-way flight deals from Dulles Intl to Ontario

Only flying one-way? Below are some of the best one-way flight deals from Dulles Intl to Ontario found on KAYAK recently.

Recent last minute flight deals from Dulles Intl to Ontario

Leaving soon but still want a bargain? Check out these latest deals for last minute flights from Dulles Intl to Ontario.

Recent direct flight deals from Dulles Intl to Ontario

The latest deals for direct flights from Dulles Intl to Ontario so you can sit back and relax without the need for a layover.

Cheap bus & train deals from Dulles Intl to Ontario

Find recent round-trip train or bus tickets from Dulles Intl to Ontario.

All round-trip flight deals to Ontario

The cheapest plane tickets to Ontario found on KAYAK recently.
Discover the best prices and deals for you by selecting your travel dates.
Choose your dates
5:31 pm - 10:00 pmIAD-ONT
7h 29m1 stop
11:00 pm - 8:36 amONT-IAD
6h 36m1 stop
$287American Airlines
Find Deal
Sat, Sep 21 - Mon, Sep 23
6:49 am - 1:44 pmIAD-ONT
9h 55m1 stop
11:11 pm - 8:38 amONT-IAD
7h 27m1 stop
$289American Airlines
Find Deal
Wed, Oct 30 - Sat, Nov 2
6:00 am - 10:10 amIAD-ONT
7h 10m1 stop
11:20 am - 9:36 pmONT-IAD
7h 16m1 stop
$290Delta
Find Deal
Sat, Jul 13 - Sat, Jul 27
1:10 pm - 8:21 pmIAD-ONT
10h 11m1 stop
7:23 pm - 8:44 amONT-IAD
10h 21m2 stops
$292American Airlines
Find Deal
Sat, Aug 24 - Mon, Aug 26
5:38 pm - 11:49 pmIAD-ONT
9h 11m2 stops
7:23 pm - 8:44 amONT-IAD
10h 21m2 stops
$297American Airlines
Find Deal
Sat, Aug 24 - Mon, Aug 26
6:00 am - 10:10 amIAD-ONT
7h 10m1 stop
10:00 pm - 8:45 amONT-IAD
7h 45m1 stop
$304Delta
Find Deal
Wed, Jul 17 - Mon, Jul 29
2:23 pm - 10:27 pmIAD-ONT
11h 04m1 stop
1:55 pm - 12:54 amONT-IAD
7h 59m1 stop
$369United Airlines
Find Deal
Mon, Jun 3 - Wed, Jun 5
7:01 am - 12:15 pmIAD-ONT
8h 14m1 stop
6:25 pm - 5:25 amONT-IAD
8h 00m1 stop
$390United Airlines
Find Deal
Wed, Jul 10 - Wed, Jul 17
7:06 pm - 10:54 amIAD-ONT
18h 48m1 stop
4:00 pm - 11:59 pmONT-IAD
28h 59m1 stop
$502Alaska Airlines
Find Deal
Fri, Oct 4 - Tue, Oct 8
7:00 am - 3:26 pmIAD-ONT
11h 26m1 stop
10:00 am - 11:59 pmONT-IAD
10h 59m1 stop
$511Alaska Airlines
Find Deal
Wed, May 29 - Sat, Jun 1
6:00 am - 10:20 amIAD-ONT
7h 20m1 stop
$145Delta
Find Deal
Sat, Jun 22
7:15 am - 12:17 pmIAD-ONT
8h 02m1 stop
$159Delta
Find Deal
Tue, Jun 11
5:43 pm - 10:59 pmIAD-ONT
8h 16m1 stop
$178American Airlines
Find Deal
Fri, Jun 21
5:31 pm - 11:00 pmIAD-ONT
8h 29m1 stop
$188American Airlines
Find Deal
Tue, Jul 30
7:00 am - 12:45 pmIAD-ONT
8h 45m1 stop
$195United Airlines
Find Deal
Thu, May 30
7:01 am - 12:15 pmIAD-ONT
8h 14m1 stop
$219United Airlines
Find Deal
Thu, Aug 8
6:10 pm - 9:05 amIAD-ONT
17h 55m1 stop
$237Alaska Airlines
Find Deal
Tue, Jun 11
6:10 pm - 10:55 pmIAD-ONT
7h 45m1 stop
$238Southwest
Find Deal
Tue, May 28
7:00 am - 3:26 pmIAD-ONT
11h 26m1 stop
$239Alaska Airlines
Find Deal
Fri, May 31
7:00 am - 9:05 pmIAD-ONT
17h 05m2 stops
$299Southwest
Find Deal
Sat, Aug 10
7:15 am - 12:13 pmIAD-ONT
7h 58m1 stop
7:00 am - 6:53 pmONT-IAD
8h 53m1 stop
$457Delta
Find Deal
Sat, May 18 - Sat, Aug 17
1:24 pm - 9:39 pmIAD-ONT
11h 15m2 stops
7:00 am - 6:53 pmONT-IAD
8h 53m1 stop
$462Delta
Find Deal
Sat, May 18 - Sat, Aug 17
6:00 am - 10:00 amIAD-ONT
7h 00m1 stop
2:15 pm - 11:30 pmONT-IAD
6h 15m1 stop
$553Southwest
Find Deal
Tue, May 21 - Wed, May 22
11:48 am - 6:59 pmIAD-ONT
10h 11m1 stop
10:35 pm - 8:44 amONT-IAD
7h 09m1 stop
$578American Airlines
Find Deal
Mon, May 20 - Sun, Aug 18
4:25 pm - 10:30 pmIAD-ONT
9h 05m1 stop
12:30 pm - 11:35 pmONT-IAD
8h 05m1 stop
$596Southwest
Find Deal
Mon, May 20 - Thu, May 23
4:05 pm - 8:53 pmIAD-ONT
7h 48m1 stop
6:25 pm - 5:25 amONT-IAD
8h 00m1 stop
$684United Airlines
Find Deal
Fri, May 17 - Fri, May 24
8:15 am - 12:40 pmIAD-ONT
7h 25m1 stop
6:25 pm - 5:25 amONT-IAD
8h 00m1 stop
$694United Airlines
Find Deal
Mon, May 20 - Sun, Aug 18
6:50 am - 7:14 pmIAD-ONT
15h 24m2 stops
10:00 am - 11:59 pmONT-IAD
10h 59m1 stop
$707Alaska Airlines
Find Deal
Tue, May 21 - Mon, Jun 3
9:05 am - 3:13 pmIAD-ONT
9h 08m1 stop
10:00 am - 11:59 pmONT-IAD
10h 59m1 stop
$858Alaska Airlines
Find Deal
Tue, May 21 - Sun, May 26
2:14 pm - 6:59 pmIAD-ONT
7h 45m1 stop
10:29 pm - 8:54 amONT-IAD
7h 25m1 stop
$862American Airlines
Find Deal
Mon, May 20 - Fri, May 31

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 June and July, where the average cost of tickets is $463 and $448 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 ($178), and the lowest round-trip tickets were found on American Airlines ($287) and Delta ($290).

Good to know

Low season

February

High season

August

Cheapest flight

$145
Best time to beat the crowds with an average 37% drop in price.
Most popular time to fly and prices are also 9% 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 $287 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 $337 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 $515 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 10673 reviews
8.0Entertainment
7.4Food
8.2Boarding
7.9Comfort
8.6Crew
Airline reviews

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

6.0 GoodEliza, Apr 2024SAN - LAX
Read more about Delta reviews

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.

Flight diverted in SD. Later take off in Seattle by 1.3hrs

Crew was not friendly when I went to request a seat change.

Really impressive staff at airport and on plane, especially given how busy it was

Was a great smooth flight from Detroit to San Diego.

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.

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.

Awful! The flight was delayed and we sat on the plane in DCA for an hour because fuel was out in the wrong part of the plane and would not be accessible during flight. So the plane had to be refueled in correct tank. They also allowed someone to get off of the plane. This delayed my six hour flight by an hour and made me miss my connecting flight. I ran to new gate and American Airlines agents new about the delay and even knew that I was trying to make the connection. They knew thru communication with my friend while in flight that I was in the airport and running to the new gate and they still closed the gate and refused to let me on the new flight despite plane still being at the gate. It was horrible and I had to be rebooked on a flight for 24 hours later. This has been a nightmare and if American Airlines can cause customers to be delayed and then have zero empathy as having an on time flight was more important to them than helping a customer who was delayed by no fault of her own, then it's seems that it's not a company that I want to continue to give my loyalty to. I'm so disgusted.

Help was available but timing was bad in my case

It was a horrible snow storm, but updates were inconsistent and the app never displayed a remotely accurate time or gate until very close to boarding.

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.
6/22Sat
1 stopDelta
7h 20mIAD-ONT
$145
6/11Tue
1 stopDelta
8h 02mIAD-ONT
$159
6/21Fri
1 stopAmerican Airlines
8h 16mIAD-ONT
$178
7/30Tue
1 stopAmerican Airlines
8h 29mIAD-ONT
$188
5/30Thu
1 stopUnited Airlines
8h 45mIAD-ONT
$195
8/8Thu
1 stopUnited Airlines
8h 14mIAD-ONT
$219
6/11Tue
1 stopAlaska Airlines
17h 55mIAD-ONT
$237
5/28Tue
1 stopSouthwest
7h 45mIAD-ONT
$238
5/31Fri
1 stopAlaska Airlines
11h 26mIAD-ONT
$239
8/10Sat
2 stopsSouthwest
17h 05mIAD-ONT
$299

Search by stops

Search by airline

Search by price

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.
5/18Sat
multi-stopDelta
7h 58mIAD-ONT
8/17Sat
multi-stopDelta
8h 53mONT-IAD
$457
5/18Sat
multi-stopDelta
11h 15mIAD-ONT
8/17Sat
multi-stopDelta
8h 53mONT-IAD
$462
5/21Tue
multi-stopSouthwest
7h 00mIAD-ONT
5/22Wed
multi-stopSouthwest
6h 15mONT-IAD
$553
5/20Mon
multi-stopAmerican Airlines
10h 11mIAD-ONT
8/18Sun
multi-stopAmerican Airlines
7h 09mONT-IAD
$578
5/20Mon
multi-stopSouthwest
9h 05mIAD-ONT
5/23Thu
multi-stopSouthwest
8h 05mONT-IAD
$596
5/17Fri
multi-stopUnited Airlines
7h 48mIAD-ONT
5/24Fri
multi-stopUnited Airlines
8h 00mONT-IAD
$684
5/20Mon
multi-stopUnited Airlines
7h 25mIAD-ONT
8/18Sun
multi-stopUnited Airlines
8h 00mONT-IAD
$694
5/21Tue
multi-stopAlaska Airlines
15h 24mIAD-ONT
6/3Mon
multi-stopAlaska Airlines
10h 59mONT-IAD
$707
5/21Tue
multi-stopAlaska Airlines
9h 08mIAD-ONT
5/26Sun
multi-stopAlaska Airlines
10h 59mONT-IAD
$858
5/20Mon
multi-stopAmerican Airlines
7h 45mIAD-ONT
5/31Fri
multi-stopAmerican Airlines
7h 25mONT-IAD
$862

Search by stops

Search by airline

Search by price

Washington Dulles Airport - Ontario Flights

Departure:

Washington Dulles Airport (undefined)United States

Destination:

Ontario (ONT)United States

Return flight deals:

Ontario - Washington Dulles Airport

Cabin classes: