ONT - IAD

$80 Find Cheap Flights from Ontario to Washington Dulles Airport

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 Dulles Intl departing on 4/23. 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 Washington, D.C. Dulles Intl Airport

 
These are the airlines KAYAK users have selected most often from within our search results in flight searches from Ontario to Washington, D.C., 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 Ontario to Washington, D.C., as well as popular online travel agencies
Travelers love KAYAK
41,299,237 searches in the past 7 days on KAYAK

Save 23% or moreCompare multiple travel sites with one search.

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

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

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

Everything you should know

Cheapest round-trip
$205
Typical prices: $484-$378
Frontier
Thu 4/23Mon 6/15
ONT - IAD • 1 stop
Cheapest one-way
$80
Typical prices: $224-$297
Frontier
Thu 4/23
ONT - IAD • 1 stop
Top airlines
Cheapest • from $205 (round-trip)
Best reviews • 8.0 score
Airline reviews
Airline reviews
+1
+1
Airline reviews
Airline reviews
+1
Nonstop flights
Not available
There are currently no direct flights between Ontario and Dulles Intl. You'll need at least 1 connection.
Insights
Insights
Insights
Insights
Top layover airports
Cheapest • Avg $290 (round-trip)
Shortest trip • 7h 07m (one-way)
Insights
Insights
Insights
Insights
When to book
in advance
Our data shows that travelers who book at least 4 weeks in advance save around 44% compared to booking last minute.
Insights
Insights
Insights
Insights
When to travel
Cheapest • 35% price drop
Most popular
Good to know
Good to know
+1
+1
Good to know
Good to know
+1
Start a new search
KAYAK searches 100s of sites at once to find you the best travel deals.
We hope you love your trip to Dulles Intl!
Flight Deals
Booking Insights
Flight Deals

Cheap Flights from Ontario to Dulles Intl (ONT-IAD)

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

Thu, Apr 23 - Mon, Jun 15
Frontier Logo
6:15 am - 6:12 pm
ONT
-
IAD
8h 57m
1 stop
Frontier Logo
9:20 am - 7:48 pm
IAD
-
ONT
13h 28m
1 stop
$205Frontier
Tue, May 26 - Tue, Jun 2
Frontier Logo
4:39 pm - 8:12 am
ONT
-
IAD
12h 33m
1 stop
Frontier Logo
9:12 am - 3:44 pm
IAD
-
ONT
9h 32m
1 stop
$210Frontier
Tue, May 26 - Fri, May 29
Frontier Logo
4:39 pm - 8:12 am
ONT
-
IAD
12h 33m
1 stop
Frontier Logo
9:12 am - 7:32 pm
IAD
-
ONT
13h 20m
1 stop
$215Frontier
Thu, May 28 - Mon, Jun 1
Frontier Logo
3:30 pm - 8:12 am
ONT
-
IAD
13h 42m
1 stop
Frontier Logo
9:12 am - 3:09 pm
IAD
-
ONT
8h 57m
1 stop
$220Frontier
Mon, Jun 1 - Sat, Jun 6
Frontier Logo
3:30 pm - 8:12 am
ONT
-
IAD
13h 42m
1 stop
Frontier Logo
9:12 am - 3:09 pm
IAD
-
ONT
8h 57m
1 stop
$222Frontier
Tue, May 26 - Fri, May 29
Frontier Logo
4:39 pm - 8:12 am
ONT
-
IAD
12h 33m
1 stop
Frontier Logo
9:12 am - 7:32 pm
IAD
-
ONT
13h 20m
1 stop
$228Frontier
Tue, Jun 2 - Wed, Jun 10
Frontier Logo
4:39 pm - 8:12 am
ONT
-
IAD
12h 33m
1 stop
Frontier Logo
9:20 am - 7:48 pm
IAD
-
ONT
13h 28m
1 stop
$230Frontier
Thu, Jun 4 - Sat, Jun 13
Frontier Logo
3:30 pm - 8:12 am
ONT
-
IAD
13h 42m
1 stop
Frontier Logo
9:20 am - 3:09 pm
IAD
-
ONT
8h 49m
1 stop
$235Frontier
Wed, May 20 - Sat, May 23
Frontier Logo
1:50 pm - 8:12 am
ONT
-
IAD
15h 22m
1 stop
Frontier Logo
9:12 am - 7:32 pm
IAD
-
ONT
13h 20m
1 stop
$241Frontier
Thu, Jun 11 - Sat, Jun 27
Frontier Logo
3:34 pm - 7:50 am
ONT
-
IAD
13h 16m
1 stop
Frontier Logo
9:20 am - 7:48 pm
IAD
-
ONT
13h 28m
1 stop
$249Frontier
Booking Insights

KAYAK's insights & trends for Ontario to Dulles Intl flights

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

How much is a round-trip flight from Ontario to Washington, D.C. Dulles Intl Airport?

This analysis is based on the cheapest round-trip price found on KAYAK in the last 12 months by searching for a flight from Ontario to Washington, D.C. Dulles Intl Airport departing in April.

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

To calculate monthly average prices, KAYAK takes all prices for each month over the last year for round-trip flights from Ontario to Washington, D.C. Dulles Intl Airport, 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 Washington, D.C. Dulles Intl Airport is July, where tickets cost $306 (return) on average. On the other hand, the most expensive months are January and November, where the average cost of round-trip tickets is $807 and $686 respectively.

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

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 Washington, D.C. Dulles Intl Airport, 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 Washington, D.C. Dulles Intl Airport, you should book around 4 weeks before departure, which saves you about 44% compared to booking last minute. For the absolute cheapest price, our data suggests you should book 23 weeks before departure.

Good to know

Low seasonFebruary
Cheapest flight$80
Best time to beat the crowds with an average 6% drop in price.
Most popular time to fly and prices are also 36% lower on average.
Flight from Ontario to Washington Dulles Airport

When to book flights from Ontario to Dulles Intl

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

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

    In the last 3 days, the lowest price for a flight from Ontario to Washington, D.C. Dulles Intl Airport was $80 for a one-way ticket and $205 for a round-trip.

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

    No

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

    Ontario airport is called Ontario and the only airport in Washington Dulles Airport is Washington, D.C. Dulles Intl.

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

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

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

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

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

    The two airlines most popular with KAYAK users for flights from Ontario to Washington, D.C. are Southwest and Delta. With an average price for the route of $447 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 $377 and an overall rating of 7.9.

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

    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 Washington Dulles Airport.

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

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

    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 Washington Dulles Airport with an airline and back to Ontario with another airline. Booking your flights between Ontario and IAD 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 Ontario to Washington Dulles Airport?

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

Reviews of the top 5 airlines serving from Ontario to Dulles Intl

 
See real verified KAYAK customer reviews for airlines flying from Ontario to Washington, D.C.. 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 Dulles Intl? 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 4337 reviews
8.0Comfort
8.6Crew
8.1Boarding
7.0Food
7.5Entertainment
Airline reviews

It was good from LAX to Phoenix, But the connection in Phoenix to Tulsa was not that great. The staff on both flights were great. The choice of free entertainment was ok nothing to brag about. The 45 min delay because of some electrical issue wasn't great from Phoenix to Tulsa. We sat there with hardly any air, The seat I had was between windows so the side of the plane pushed in on you. My being a bigger man it then made the seating area uncomfortable. The seats on the plane had no power to connect to recharge your phone or anything. I would recommend that they should look into a slot or clamp to hold your phone to enjoy while watching the entertainment choices hands-free. Also make it possible to raise the inner seat by the window be able to raise the arm rest up to make more room for larger people to set more comfortably. I would also say other then that stop price gouging the airfare or nickel and diming everything. Not fair for people having to fly for emergencies and be paying for higher prices due to the season or holidays. Your making your money either way and the cost of flying is still going to be the same regardless if there's 100 people or 200 people.

10.0 ExcellentAnthony & Kathy, Mar 2026
LAX - PHX
Read more Southwest reviews

It was good from LAX to Phoenix, But the connection in Phoenix to Tulsa was not that great. The staff on both flights were great. The choice of free entertainment was ok nothing to brag about. The 45 min delay because of some electrical issue wasn't great from Phoenix to Tulsa. We sat there with hardly any air, The seat I had was between windows so the side of the plane pushed in on you. My being a bigger man it then made the seating area uncomfortable. The seats on the plane had no power to connect to recharge your phone or anything. I would recommend that they should look into a slot or clamp to hold your phone to enjoy while watching the entertainment choices hands-free. Also make it possible to raise the inner seat by the window be able to raise the arm rest up to make more room for larger people to set more comfortably. I would also say other then that stop price gouging the airfare or nickel and diming everything. Not fair for people having to fly for emergencies and be paying for higher prices due to the season or holidays. Your making your money either way and the cost of flying is still going to be the same regardless if there's 100 people or 200 people.

Southwest was greaat! The most expensive but the least upsetting for those we were flying to see.

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

Flight boarded late after announcing on time boarding. Flight arrived only a little late despite late departure. Had trouble connecting to WiFi

The Southwest experience has definitely taken a dive from its early days. You can no longer deferentiate from other airlines. Air travel is too expensive. Southwest is no longer budget friendly. They have lost me as a loyal customer.

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

The seats are now more narrow. I paid for front row the seats in the front are even more narrow than before.

The wifi on the plane is great. The only issue that I have is that I prefer an aisle seat and on my trips this week, I was either in the middle or window. If we can work to secure aisle seating, I will be thrilled. Nice trip.

Fast, lovely scenery, great info on the Delta flight screen about landmarks we were flying over. Great landing!

Long flight but comfortable and not freezing as I have experienced on Hawaiian flights to the islands. They gave us blankets just in case. Nice touch.

I took seat 15A in anticipation of window seat, there is no window.

Flight late, the waited for a long time for “personal” to arrive at gate to dock the plane in Rochester. So annoying. This flight was expected, why aren’t personel available for the jet bridge?

My recent experience was excellent on Delta! I flew with Delta Comfort and I was really comfortable in my seat. I enjoyed the in-flight service. The flight attendants were so friendly and hospitable. I love the snack on the flight as well. This was my first time flying on Delta and I will definitely consider flying with them again.

My flight was canceled on Sunday. Rebooking took three hours. Had to pay for accommodations another night. New flight was delayed for 5 hours, all that was sent was a 12 dollar food voucher, which doesn’t tell you how to use it. Then when we landed we had to sit on the plane for an hour before we could get off.

I was in first class and literally the men behind me were so aggressively loud I moved myself to economy. This has become so common on Delta - people using audio without headphones, and men on 12am / late night flights drinking and yelling to talk to each other which prevents anyone around them from resting. Pretty crazy to have to move from first to economy (poorer service, less comfort...). Wild wild. Looking into other airlines.

Flight was warm for first few hours and quite rough

Flight was delayed by 3-hours and their fix was… complimentary pretzels.

The crew, and fellow passengers, were super gracious and kind. There seemed to be plenty of bin space even though the plane was full. It’s nice to get a glass of wine with dinner in Premiere seating, and there was a lot of food.

I liked that it was on time, however, the food was not good.

Offered to check carry on to final destination. This is the most absurd thing in the world. I'm carrying on because I need what is in the carry-on. I'm okay with picking up at next stop but then I will be on much larger plane that can accommodate it. Also, if there is ever a change to your flight. Go to the airport and have the people there fix your ticket. Don't do it over the phone or online with United they screwed us up and ended up with flights for our last leg that took off before our first leg.

United is one airline which regardless of how many separate United tickets in existence, if one flight breaks down, the airline will take care of all the flights.

It was okay, the food was good, but after the landing there was not enough time for luggage and security to catch a connection. It was crowded on board.

When I went to check in at the United counter in Barcelona, Spain I had 2 different menat 2 different times in United uniforms (standing around with a couple other employees) ask me if I was traveling alone. The one man asked me 3 different ways if I was traveling alone. I am, 68 yeaers old and have all my faculties. I thought it was weird and it made me feel very uncomfortable. What difference does it make if I was traveling alone or with someone? What if I was a recent widow? That would have been horrible. They never gave me a reason why they needed to know who I was traveling with. I was hesitant to question them because I needed to be on that flight.

Crew was great. 2 1/2 hour delay was due to staff needing "rest" was avoidable and self inflicted as United not willing to hire enough crew to keep flight on time.. Ridiculous. The crew and the passengers both suffered due to this.

Fine not above and beyond as I had a connection that was delayed due to maintenance

Bad food, bad service, cold cabin with no additional blankets when asked for (they told me they don’t provide additional blankets). I’m a frequent traveler and this is one of the worst companies I traveled with (by the way I thought that I booked my ticket with Lufthansa but I didn’t see that the flights were handled by United).

Great other than a couple very drunk guys that for a while kept bumping my seat from behind. The staff did their best to control them. Even refused serving them alcohol and allowed the gal sitting next to them to move.

Good crew. Boarding delays. Almost two hours wait for the bags in DC.

It was great. Smooth flight, comfortable, left on time and landed on time.

Horrible experience upon landing. Probably more due to DCA utter incompetence than AA.

Easy boarding. Rows are smaller but that may be an older and bigger me now :)

Flight has been delayed every time I've ever taken it. Seats uncomfortable. Children behind me yelling the entire flight. Some of this is out of their control but overall just consistently not a great experience.

Poor communication ahead of time about flight delays and old planes/other equipment.

Never going to fly your airline again if it can be avoided.

Not to have gotten delayed by 2+ hours for the fourth straight American flight. They're the worst.

Other than nearly three hour delay for maintenance issues, everything went smooth

Snow delayed boarding several times, which I understand happens. Issue I had was that after we did board, pilot told us we were going to roll out to be de-iced, then on our way. We were de-iced once, taxied to the tarmac and then stopped. Sat for another 30 minutes or so, the another de-icing. Then we rolled out to a parking spot, only to sit for another hour due to a traffic stop in DCA, which I'm confident they knew would happen before we boarded. Pilot gave no updates other than we had to hold, attendants did speak to the crew, but when asked, said the pilot would be updating us. We on the ground in the plane waiting for over 2 hours. They did communicate that bathrooms would be open, but no other news until we left. Would have been better to be up front about status.

Flight was delayed. Not much information on when the flight would take off. Eventually we were told it was maintenance. App was not giving updates.

It was an early flight and most people napped/slept and the crew let us which was nice.

The crew acted like they had never done this and kept barking passive aggressive orders at people. + the security line + the delay + sitting on the tarmac for 2 hours + none of the apps or signage updating with correct times

More inflight connection. And leg space is horrible. And the paying for baggage I'd ridiculous!!!

There's no seats that lean back with little leg space i wad uncomfortable the entire flight. Your charges for extra baggage is despicable and costly!!

Remind customers of the need to have passport or new ID for boarding.

The flight never took off and we spent 7 hours at the airport

There was no food and no entertainment, so I'm not sure why these are even in the survey, as my understanding is frontier does not ever offer food without a few, not even a snack, and there are no screens so unless the flight safety talk is our entertainment why ask how we liked it?. One of the flight attendants say in the back of the plane as people filed in to their seats, yelling orders about where to put baggage and telling people to hurry up. It was the least professional experience I've ever had on a flight.

It was ok. It was expensive to check 2 bags ($75.00 per bag), and then it took a long time to wait for shuttle to take us from one terminal to the terminal where the plane was taking off at LAX. And all of this for a flight where we had to pay for any food or drink that was not water.

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.

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.

Everything you need to know for your flight from Ontario to Dulles Intl

Information on your arrival and departure airports