How long is the flight from Ontario to Washington, D.C. Dulles Intl Airport?

Airlines like Alaska Airlines and Delta fly from Ontario to Washington, D.C. Dulles Intl Airport in about 7h 43m. The time it takes to get you to your destination can typically vary by up to 13h 40m. Ontario and Washington, D.C. Dulles Intl Airport are separated by a distance of 2236 mi. This flight may include one or multiple stops.

What are the cheapest airlines flying from Ontario to Washington, D.C. Dulles Intl Airport round-trip?

Cheapflights users have booked flights from Ontario to Washington, D.C. Dulles Intl Airport round-trip from $160. Other airlines that can offer you cheap pricing are American Airlines, from $278, and United Airlines, from $298. Users have found that Frontier is 64% cheaper than the other options available to this destination.

What are the cheapest airlines to fly from Ontario to Washington, D.C. Dulles Intl Airport one-way?

To fly one-way, consider booking your trip with Frontier, which is currently one of the cheapest options available, starting at $71. American Airlines flights start at $149 while deals on United Airlines start at $149 one-way.

In terms of precipitation, rainfall in Washington, D.C. Dulles Intl Airport ranges from 2.6 - 4.0 inches per month. May is typically the wettest month, when rainfall can reach 4.0 in. February is typically the driest time to visit Washington, D.C. Dulles Intl Airport when rainfall is around 2.6 in.

If weather is an important factor for your trip to Washington, D.C. Dulles Intl Airport, use this chart to help with planning. For those seeking warmer temperatures, July is the ideal time of year to visit, when temperatures reach an average of 80.6 F. Travelers looking to avoid the cold should look outside of January, when temperatures are typically at their lowest (around 35.6 F).

What are the most popular airlines that fly from Ontario to Washington, D.C. Dulles Intl Airport?

When booking a flight from Ontario to Washington, D.C. Dulles Intl Airport, you may want to consider flying on United Airlines, Southwest or American Airlines as they are the most popular for this route.

Most accurate provider : When it comes to deals on Ontario-Washington, D.C. Dulles Intl Airport flights, users find the pricing of eDreams to be most consistent on Cheapflights vs. eDreams Users can find the same prices on Ontario-Washington, D.C. Dulles Intl Airport flight deals on Cheapflights vs. eDreams >95% of the time. Price accuracy is based on data collected from Ontario-Washington, D.C. Dulles Intl Airport flight searches over the past month and is updated monthly.

Most trusted provider : When it comes to deals on Ontario-Washington, D.C. Dulles Intl Airport flights, Cheapflights users trust eDreams the most. eDreams has received a user feedback score of 3 out of 3 stars (3 being the best), meaning they have been trusted the most by Cheapflights users looking for Ontario-Washington, D.C. Dulles Intl Airport flight deals. Provider user feedback score is based on Cheapflights searches over the past month and is updated monthly.

What airport do you fly from for flights from Ontario to Washington, D.C. Dulles Intl?

Most people fly from Ontario (ONT) if they book a flight from Ontario to Washington, D.C. Dulles Intl. On average, Ontario has 0 outbound flights to Washington, D.C. Dulles Intl per day from 5 airlines. Ontario is conveniently located just 3.1 mi from Ontario’s city center.

Can I find deals for flights from Ontario to Dulles Intl that include hotel bookings?

Yes. In addition to deals on Ontario to Dulles Intl flights, Cheapflights offers vacation packages that include both flights and hotel.

How can I find direct flights from Ontario to Dulles Intl?

After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from Ontario to Dulles Intl.

Can I find deals for business class flights from Ontario to Dulles Intl?

Yes. Cheapflights offers flight deals from Ontario to Dulles Intl by cabin class. In addition to browsing deals, you can also filter by cabin class on the search results page after making a search.

$91+ Flights from Ontario to Washington, D.C. Dulles Intl Airport

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Cheap flight deals from Ontario to Dulles Intl

Cheapest flights from Ontario to Dulles Intl
Explore the most affordable flight options available from Ontario to Dulles Intl. Find the lowest fares from popular airlines and budget airlines, with prices last updated on December 28, 2025.

Sun 12/287:10 amONT - IAD

1 stop7h 07mAmerican Airlines

Thu 1/16:05 amIAD - ONT

1 stop10h 47mAmerican Airlines

Deal found 12/26

$684

Tue 12/3010:40 pmONT - IAD

1 stop11h 47mAmerican Airlines

Sat 1/36:35 amIAD - ONT

1 stop17h 23mAmerican Airlines

Deal found 12/27

$688

Mon 12/2910:40 pmONT - IAD

1 stop11h 47mAmerican Airlines

Fri 1/26:35 amIAD - ONT

1 stop17h 23mAmerican Airlines

Deal found 12/26

$755

Sun 12/2810:40 pmONT - IAD

1 stop11h 47mAmerican Airlines

Sun 1/41:40 pmIAD - ONT

2 stops13h 06mAmerican Airlines

Deal found 12/25

$834

Mon 12/294:36 pmONT - IAD

1 stop10h 37mAlaska Airlines

Fri 1/27:33 amIAD - ONT

1 stop11h 09mAlaska Airlines

Deal found 12/26

$864

Sun 12/2812:20 pmONT - IAD

1 stop8h 05mSouthwest

Sun 1/45:00 amIAD - ONT

1 stop7h 10mSouthwest

Deal found 12/26

$865

Best flights from Ontario to Dulles Intl
Discover carefully curated flight deals from Ontario to Dulles Intl that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated December 28, 2025.

Fri 1/304:03 pmONT - IAD

1 stop21h 23mAlaska Airlines

Sun 2/16:04 pmIAD - ONT

1 stop19h 55mAlaska Airlines

Deal found 12/26

$306

Thu 1/2210:30 pmONT - IAD

1 stop7h 43mDelta

Mon 1/263:42 pmIAD - ONT

1 stop8h 23mDelta

Deal found 12/26

$319

Thu 1/296:00 amONT - IAD

1 stop31h 26mAlaska Airlines

Sun 2/16:04 pmIAD - ONT

1 stop19h 55mAlaska Airlines

Deal found 12/27

$306

Wed 1/214:03 pmONT - IAD

1 stop21h 23mAlaska Airlines

Tue 1/276:04 pmIAD - ONT

1 stop24h 04mAlaska Airlines

Deal found 12/26

$306

Fri 2/66:00 amONT - IAD

1 stop31h 26mAlaska Airlines

Sun 2/86:04 pmIAD - ONT

1 stop19h 55mAlaska Airlines

Deal found 12/27

$326

Fri 1/234:03 pmONT - IAD

1 stop21h 23mAlaska Airlines

Fri 1/306:04 pmIAD - ONT

1 stop29h 32mAlaska Airlines

Deal found 12/26

$327

Fri 1/234:03 pmONT - IAD

1 stop21h 23mAlaska Airlines

Tue 2/36:04 pmIAD - ONT

1 stop29h 32mAlaska Airlines

Deal found 12/26

$327

Mon 1/2611:53 amONT - IAD

1 stop25h 33mAlaska Airlines

Mon 2/26:04 pmIAD - ONT

1 stop29h 32mAlaska Airlines

Deal found 12/27

$327

Sat 1/314:03 pmONT - IAD

1 stop21h 23mAlaska Airlines

Mon 2/26:04 pmIAD - ONT

1 stop29h 32mAlaska Airlines

Deal found 12/27

$345

Thu 2/266:14 amONT - IAD

1 stop20h 26mAlaska Airlines

Mon 3/26:27 pmIAD - ONT

1 stop31h 17mAlaska Airlines

Deal found 12/25

$345

Tue 3/34:02 pmONT - IAD

1 stop22h 18mAlaska Airlines

Sat 3/77:05 amIAD - ONT

1 stop19h 27mAlaska Airlines

Deal found 12/26

$364

Thu 2/196:14 amONT - IAD

1 stop20h 26mAlaska Airlines

Mon 2/237:05 amIAD - ONT

1 stop19h 27mAlaska Airlines

Deal found 12/26

$365

Last-minute flights from Ontario to Dulles Intl
Discover last-minute flight deals from Ontario to Dulles Intl. Data last updated December 28, 2025 and is based on user searches.

Sun 1/118:31 amONT - IAD

1 stop9h 25mFrontier

Sun 1/1811:00 amIAD - ONT

1 stop11h 01mFrontier

Deal found 12/27

$252

Sun 1/1110:30 pmONT - IAD

2 stops17h 39mDelta

Sat 1/177:30 amIAD - ONT

1 stop9h 26mDelta

Deal found 12/27

$364

Thu 1/158:02 amONT - IAD

1 stop9h 02mFrontier

Sun 1/1811:00 amIAD - ONT

1 stop11h 01mFrontier

Deal found 12/27

$217

Thu 1/158:02 amONT - IAD

1 stop9h 02mFrontier

Mon 1/196:00 amIAD - ONT

2 stops20h 59mFrontier

Deal found 12/27

$292

Thu 1/2210:30 pmONT - IAD

1 stop7h 43mDelta

Mon 1/263:42 pmIAD - ONT

1 stop8h 23mDelta

Deal found 12/26

$319

Thu 1/222:06 pmONT - IAD

1 stop16h 49mFrontier

Sun 2/110:50 amIAD - ONT

2 stops11h 42mFrontier

Deal found 12/27

$366

Fri 1/234:03 pmONT - IAD

1 stop21h 23mAlaska Airlines

Tue 2/36:04 pmIAD - ONT

1 stop29h 32mAlaska Airlines

Deal found 12/26

$327

Fri 1/234:03 pmONT - IAD

1 stop21h 23mAlaska Airlines

Sat 1/316:04 pmIAD - ONT

1 stop19h 55mAlaska Airlines

Deal found 12/27

$346

Sun 1/256:00 amONT - IAD

1 stop31h 26mAlaska Airlines

Sat 2/76:04 pmIAD - ONT

1 stop19h 55mAlaska Airlines

Deal found 12/27

$365

Tue 1/274:03 pmONT - IAD

1 stop21h 23mAlaska Airlines

Sat 2/287:05 amIAD - ONT

1 stop19h 27mAlaska Airlines

Deal found 12/26

$306

Fri 1/306:00 amONT - IAD

1 stop31h 26mAlaska Airlines

Thu 2/56:04 pmIAD - ONT

1 stop24h 04mAlaska Airlines

Deal found 12/25

$326

Sat 1/314:03 pmONT - IAD

1 stop21h 23mAlaska Airlines

Mon 2/26:04 pmIAD - ONT

1 stop29h 32mAlaska Airlines

Deal found 12/27

$345

One-way flights from Ontario to Dulles Intl
Search for one-way flight options from Ontario to Dulles Intl. Find affordable one-way fares based on user searches. Data last updated December 28, 2025.

Thu 1/158:02 amONT - IAD

1 stop9h 02mFrontier

Deal found 12/27

$91

Thu 1/88:31 amONT - IAD

1 stop9h 25mFrontier

Deal found 12/27

$112

Wed 2/118:10 amONT - IAD

2 stops30h 47mFrontier

Deal found 12/25

$117

Sun 1/118:31 amONT - IAD

1 stop9h 25mFrontier

Deal found 12/27

$126

Sun 1/256:20 amONT - IAD

2 stops31h 08mFrontier

Deal found 12/27

$134

Mon 1/1910:18 pmONT - IAD

3 stops57h 24mMultiple Airlines

Deal found 12/26

$158

Sat 1/176:00 amONT - IAD

1 stop7h 31mAmerican Airlines

Deal found 12/26

$159

Sat 1/1712:41 pmONT - IAD

1 stop7h 56mDelta

Deal found 12/25

$160

Tue 3/314:00 pmONT - IAD

2 stops23h 43mFrontier

Deal found 12/26

$163

Find flight deals from Ontario to Dulles Intl

Most accurate provider	eDreams 3 stars
Most trusted provider	eDreams 3 stars
Round-trip from	$217 (Frontier)
One-way from	$91 (Mytrip)
Popular in	November
Cheapest in	July
Average price	$673

Provider with most accurate pricing for Ontario-Washington, D.C. Dulles Intl flight deals.

Search Deals

Provider most trusted by Cheapflights users for Ontario-Washington, D.C. Dulles Intl flights.

Search Deals

From Ontario to Washington, D.C. Dulles Intl

Search Deals

One-way flight from Ontario to Washington, D.C. Dulles Intl

Search Deals

Highest demand for flights based on searches. 22% potential increase in price ($134 potential increase over avg. RT price).

Search Deals

Cheapest flight prices on average. 5% potential price decrease ($22 potential savings vs. average RT price).

Search Deals

Average for round-trip flights in December 2025

Search Deals

Cheapflights Fare Finder

Use the filters below to find and compare flights from Ontario to Washington, D.C. Dulles Intl Airport that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

OntarioWashington, D.C.

ONT - IAD

ONTIAD

Ontario

Fri 1/30

4:03 pm-4:26 pm

1 stop21h 23m

Washington, D.C. Dulles Intl

Sun 2/1

6:04 pm-10:59 am

1 stop19h 55m

$306

OntarioWashington, D.C.

ONT - IAD

ONTIAD

Ontario

Thu 1/29

6:00 am-4:26 pm

1 stop31h 26m

Washington, D.C. Dulles Intl

Sun 2/1

6:04 pm-10:59 am

1 stop19h 55m

$306

OntarioWashington, D.C.

ONT - IAD

ONTIAD

Ontario

Wed 1/21

4:03 pm-4:26 pm

1 stop21h 23m

Washington, D.C. Dulles Intl

Tue 1/27

6:04 pm-3:08 pm

1 stop24h 04m

$306

OntarioWashington, D.C.

ONT - IAD

ONTIAD

Ontario

Thu 1/22

10:30 pm-9:13 am

1 stop7h 43m

Washington, D.C. Dulles Intl

Mon 1/26

3:42 pm-9:05 pm

1 stop8h 23m

$319

OntarioWashington, D.C.

ONT - IAD

ONTIAD

Ontario

Fri 2/6

6:00 am-4:26 pm

1 stop31h 26m

Washington, D.C. Dulles Intl

Sun 2/8

6:04 pm-10:59 am

1 stop19h 55m

$326

OntarioWashington, D.C.

ONT - IAD

ONTIAD

Ontario

Fri 1/23

4:03 pm-4:26 pm

1 stop21h 23m

Washington, D.C. Dulles Intl

Fri 1/30

6:04 pm-8:36 pm

1 stop29h 32m

$327

OntarioWashington, D.C.

ONT - IAD

ONTIAD

Ontario

Fri 1/23

4:03 pm-4:26 pm

1 stop21h 23m

Washington, D.C. Dulles Intl

Tue 2/3

6:04 pm-8:36 pm

1 stop29h 32m

$327

OntarioWashington, D.C.

ONT - IAD

ONTIAD

Ontario

Mon 1/26

11:53 am-4:26 pm

1 stop25h 33m

Washington, D.C. Dulles Intl

Mon 2/2

6:04 pm-8:36 pm

1 stop29h 32m

$327

OntarioWashington, D.C.

ONT - IAD

ONTIAD

Ontario

Sat 1/31

4:03 pm-4:26 pm

1 stop21h 23m

Washington, D.C. Dulles Intl

Mon 2/2

6:04 pm-8:36 pm

1 stop29h 32m

$345

OntarioWashington, D.C.

ONT - IAD

ONTIAD

Ontario

Thu 2/26

6:14 am-5:40 am

1 stop20h 26m

Washington, D.C. Dulles Intl

Mon 3/2

6:27 pm-10:44 pm

1 stop31h 17m

$345

Flights are sorted by cheapest round-trip flights first.

Deals found on 12/27

Showing 1-10 of 23 results

Compare providers for flights from Ontario to Dulles Intl

Use the table below to compare price accuracy, trust ratings, and cancellation policies for each provider offering flight deals from Ontario to Dulles Intl in December.

Provider	Price Accuracy	Trust Score*
Expedia	Price Accuracy2 stars	Trust Score*3 stars
FlightHub	Price Accuracy3 stars	Trust Score*1 star
eDreams	Price Accuracy3 stars	Trust Score*3 stars
Priceline	Price Accuracy1 star	Trust Score*3 stars

*The Trust Score is based on feedback from users after their booking experience. It measures overall satisfaction, helping us identify issues like hidden fees, problems during the ticketing process, and the quality of customer service. This score is our best indicator of the provider's quality and reliability.

Most accurate provider: When it comes to deals on Ontario-Washington, D.C. Dulles Intl Airport flights, users find the pricing of eDreams to be most consistent on Cheapflights vs. eDreams Users can find the same prices on Ontario-Washington, D.C. Dulles Intl Airport flight deals on Cheapflights vs. eDreams >95% of the time. Price accuracy is based on data collected from Ontario-Washington, D.C. Dulles Intl Airport flight searches over the past month and is updated monthly.
Most trusted provider: When it comes to deals on Ontario-Washington, D.C. Dulles Intl Airport flights, Cheapflights users trust eDreams the most. eDreams has received a user feedback score of 3 out of 3 stars (3 being the best), meaning they have been trusted the most by Cheapflights users looking for Ontario-Washington, D.C. Dulles Intl Airport flight deals. Provider user feedback score is based on Cheapflights searches over the past month and is updated monthly.

Best time to book a flight from Ontario to Dulles Intl

Have a flexible travel schedule? Discover the best time to fly to Dulles Intl from Ontario with our price prediction graph.

Estimated round-trip price

Rates are based on past data. Find the cheapest month and day to book your flight based on your travel requirements, then search for cheap deals.

Cheapflights Insights

Everything you need to know about your flight from Ontario to Washington, D.C. Dulles Intl Airport

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

The price you pay for your flight from Ontario to Washington, D.C. Dulles Intl Airport may vary depending on when you book. For the best chance of a lower fare, look to book 54 days in advance of your trip. Fares are likely to increase a fortnight or so before your departure date.

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

Currently, June is the cheapest month in which you can book a flight from Ontario to Washington, D.C. Dulles Intl Airport (average of $142). Flying from Ontario to Washington, D.C. Dulles Intl Airport in November is currently the most expensive (average of $267). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

What is the cheapest time of day to fly from ONT to IAD?

A simple way to save on the total cost of your ticket is to fly from Ontario to Washington, D.C. Dulles Intl Airport in the afternoon. If you’re flexible enough to do this you can expect to save up to 15% on your trip compared to booking a flight in the morning.

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

Travelers seeking maximum savings on their Ontario to Washington, D.C. Dulles Intl Airport flight should consider departing on Monday afternoons when fares are most often at their lowest. Monday mornings flights should be avoided if possible as fares are typically the most expensive at this time.

Reviews of airlines servicing Dulles Intl

Read reviews from past customers who have flown Southwest, Delta, and United Airlines from Ontario to Washington, D.C. Dulles Intl Airport. Users can see the overall rating for each airline as well as how each is rated in terms of entertainment options, comfort, food, crew/service, and boarding process.

Southwest

8.0

Very good

4,256 reviews

Reviews

1 / 20

10.0

Excellent

William Drew,Nov 2025

SJC - HNL

Flight crew was amazing! Usually they're very good on Southwest, but this crew went above and beyond. I have never ever seen so many rounds of drink service on a flight before.

Southwest

8.0

Very good

4,256 reviews

Southwest

8.0

Very good

4,256 reviews

Reviews

1 / 20

10.0

Excellent

William Drew,Nov 2025

SJC - HNL

Flight crew was amazing! Usually they're very good on Southwest, but this crew went above and beyond. I have never ever seen so many rounds of drink service on a flight before.

Delta

7.9

Good

8,019 reviews

Southwest

8.0

Very good

4,256 reviews

Reviews

1 / 20

10.0

Excellent

William Drew,Nov 2025

SJC - HNL

Flight crew was amazing! Usually they're very good on Southwest, but this crew went above and beyond. I have never ever seen so many rounds of drink service on a flight before.

United Airlines

7.4

Good

9,113 reviews

Southwest

8.0

Very good

4,256 reviews

Reviews

1 / 20

10.0

Excellent

William Drew,Nov 2025

SJC - HNL

Flight crew was amazing! Usually they're very good on Southwest, but this crew went above and beyond. I have never ever seen so many rounds of drink service on a flight before.

American Airlines

7.2

Good

11,072 reviews

Southwest

8.0

Very good

4,256 reviews

Reviews

1 / 20

10.0

Excellent

William Drew,Nov 2025

SJC - HNL

Flight crew was amazing! Usually they're very good on Southwest, but this crew went above and beyond. I have never ever seen so many rounds of drink service on a flight before.

Frontier

5.8

Fair

3,065 reviews

Southwest

8.0

Very good

4,256 reviews

Reviews

1 / 20

10.0

Excellent

William Drew,Nov 2025

SJC - HNL

Flight crew was amazing! Usually they're very good on Southwest, but this crew went above and beyond. I have never ever seen so many rounds of drink service on a flight before.

Related info for your journey

What airport do you fly from for flights from Ontario to Washington, D.C. Dulles Intl?
Most people fly from Ontario (ONT) if they book a flight from Ontario to Washington, D.C. Dulles Intl. On average, Ontario has 0 outbound flights to Washington, D.C. Dulles Intl per day from 5 airlines. Ontario is conveniently located just 3.1 mi from Ontario’s city center.
How long is the flight from Ontario to Washington, D.C. Dulles Intl Airport?
Airlines like Alaska Airlines and Delta fly from Ontario to Washington, D.C. Dulles Intl Airport in about 7h 43m. The time it takes to get you to your destination can typically vary by up to 13h 40m. Ontario and Washington, D.C. Dulles Intl Airport are separated by a distance of 2236 mi. This flight may include one or multiple stops.
What are the cheapest airlines flying from Ontario to Washington, D.C. Dulles Intl Airport round-trip?
Cheapflights users have booked flights from Ontario to Washington, D.C. Dulles Intl Airport round-trip from $160. Other airlines that can offer you cheap pricing are American Airlines, from $278, and United Airlines, from $298. Users have found that Frontier is 64% cheaper than the other options available to this destination.
What are the cheapest airlines to fly from Ontario to Washington, D.C. Dulles Intl Airport one-way?
To fly one-way, consider booking your trip with Frontier, which is currently one of the cheapest options available, starting at $71. American Airlines flights start at $149 while deals on United Airlines start at $149 one-way.
Can I find deals for flights from Ontario to Dulles Intl that include hotel bookings?
Yes. In addition to deals on Ontario to Dulles Intl flights, Cheapflights offers vacation packages that include both flights and hotel.
How can I find direct flights from Ontario to Dulles Intl?
After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from Ontario to Dulles Intl.
Can I find deals for business class flights from Ontario to Dulles Intl?
Yes. Cheapflights offers flight deals from Ontario to Dulles Intl by cabin class. In addition to browsing deals, you can also filter by cabin class on the search results page after making a search.
What is the cheapest month to book a flight from Ontario to Washington, D.C. Dulles Intl Airport?
Currently, June is the cheapest month in which you can book a flight from Ontario to Washington, D.C. Dulles Intl Airport (average of $142). Flying from Ontario to Washington, D.C. Dulles Intl Airport in November is currently the most expensive (average of $267). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

See more FAQs

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Top 5 airlines flying from Ontario to Dulles Intl

Airline	Cheapest	Average	Flexibility	On-time
Frontier	Cheapest$187	Average$295	FlexibilityNo cancel fee	On-time62%
American Airlines	Cheapest$278	Average$389	FlexibilityNo cancel fee	On-time71%
United Airlines	Cheapest$298	Average$488	FlexibilityNo cancel fee	On-time69%
Southwest	Cheapest$318	Average$465	FlexibilityNo cancel fee	On-time63%
Delta	Cheapest$318	Average$331	FlexibilityNo cancel fee	On-timeN/A

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$91+ Cheap flights from Ontario (ONT) to Dulles Intl (IAD)

This is the cheapest one-way flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 1/15. Fares are subject to change and may not be available on all flights or dates of travel.

Find cheap flights from Ontario to Dulles Intl with Cheapflights

1. Tell us where you want to go

2. Select your favorite providers

3. Compare prices and book

Cheap flight deals from Ontario to Dulles Intl

Cheapest flights from Ontario to Dulles IntlExplore the most affordable flight options available from Ontario to Dulles Intl. Find the lowest fares from popular airlines and budget airlines, with prices last updated on December 28, 2025.

Explore the most affordable flight options available from Ontario to Dulles Intl. Find the lowest fares from popular airlines and budget airlines, with prices last updated on December 28, 2025.

Find flight deals from Ontario to Dulles Intl

Most accurate provider

Most trusted provider

Round-trip from

One-way from

Popular in

Cheapest in

Average price

Cheapflights Fare Finder

Use the filters below to find and compare flights from Ontario to Washington, D.C. Dulles Intl Airport that are best for you.

Compare providers for flights from Ontario to Dulles Intl

Provider information is updated monthly. Please note that these providers often have deals for this flight, but the availability may vary on a day-by-day basis on Cheapflights.

Use the table below to compare price accuracy, trust ratings, and cancellation policies for each provider offering flight deals from Ontario to Dulles Intl in December.

Best time to book a flight from Ontario to Dulles Intl

Have a flexible travel schedule? Discover the best time to fly to Dulles Intl from Ontario with our price prediction graph.

Cheapflights Insights

Everything you need to know about your flight from Ontario to Washington, D.C. Dulles Intl Airport

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

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

What is the cheapest time of day to fly from ONT to IAD?

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

Reviews of airlines servicing Dulles Intl

Related info for your journey

Find useful and relevant information for your journey from Ontario to Dulles Intl. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.

What airport do you fly from for flights from Ontario to Washington, D.C. Dulles Intl?

How long is the flight from Ontario to Washington, D.C. Dulles Intl Airport?

What are the cheapest airlines flying from Ontario to Washington, D.C. Dulles Intl Airport round-trip?

What are the cheapest airlines to fly from Ontario to Washington, D.C. Dulles Intl Airport one-way?

Can I find deals for flights from Ontario to Dulles Intl that include hotel bookings?

How can I find direct flights from Ontario to Dulles Intl?

Can I find deals for business class flights from Ontario to Dulles Intl?

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

Traveling to a place near Washington, D.C. Dulles Intl Airport?

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Alternative routes for Ontario to Dulles Intl

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Top 5 airlines flying from Ontario to Dulles Intl

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Cheapest flights from Ontario to Dulles Intl
Explore the most affordable flight options available from Ontario to Dulles Intl. Find the lowest fares from popular airlines and budget airlines, with prices last updated on December 28, 2025.