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

Airlines like United Airlines and Delta fly from Ontario to Washington, D.C. Dulles Intl Airport in about 7h 08m. The time it takes to get you to your destination can typically vary by up to 31m. 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 $105. Other airlines that can offer you cheap pricing are American Airlines, from $256, and Southwest, from $318. Users have found that Frontier is 82% 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 $141. American Airlines flights start at $159 while deals on Delta start at $160 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, American Airlines or Southwest as they are the most popular for this route.

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

Regardless of the time of day you decide to fly, the ticket price will remain around the same. Book flights from Ontario to Washington, D.C. Dulles Intl Airport as you normally would.

Most accurate provider : When it comes to deals on Ontario-Washington, D.C. Dulles Intl Airport flights, users find the pricing of FlightHub to be most consistent on Cheapflights vs. FlightHub Users can find the same prices on Ontario-Washington, D.C. Dulles Intl Airport flight deals on Cheapflights vs. FlightHub >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 FlightHub the most. FlightHub 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.

$124+ Cheap Flights from Ontario to Washington, D.C. Dulles Intl Airport

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Cheap flight deals from Ontario to Dulles Intl

Cheapest

Best

Last-minute

One-way

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 August 28, 2026.

Thu 10/158:35 pm -

1 stop6h 45m

Thu 10/2212:30 pm -

1 stop9h 35m

Deal found 8/28

$259

Thu 9/248:24 pm -

1 stop6h 56m

Tue 9/296:00 am -

1 stop13h 59m

Deal found 8/28

$261

Sat 9/1910:04 am -

1 stop17h 16m

Sat 9/2612:30 pm -

1 stop7h 16m

Deal found 8/27

$262

Tue 9/225:44 pm -

1 stop9h 36m

Tue 9/299:04 pm -

2 stops29h 43m

Deal found 8/27

$271

Tue 9/155:44 pm -

1 stop9h 36m

Tue 9/299:04 pm -

2 stops29h 43m

Deal found 8/28

$272

Thu 9/248:24 pm -

1 stop6h 56m

Wed 9/307:50 am -

2 stops18h 57m

Deal found 8/26

$274

Mon 9/288:24 pm -

1 stop6h 56m

Mon 10/129:06 pm -

2 stops29h 44m

Deal found 8/26

$275

Fri 10/98:35 pm -

1 stop6h 45m

Mon 10/126:00 am -

1 stop8h 16m

Deal found 8/27

$276

Fri 9/258:24 pm -

1 stop6h 56m

Thu 10/112:30 pm -

1 stop9h 09m

Deal found 8/26

$277

Tue 9/225:44 pm -

1 stop9h 36m

Thu 10/112:30 pm -

1 stop9h 09m

Deal found 8/24

$279

Wed 9/232:30 pm -

1 stop12h 50m

Wed 9/307:50 am -

2 stops18h 57m

Deal found 8/27

$280

Wed 10/215:25 pm -

1 stop9h 55m

Wed 11/48:05 am -

2 stops42h 46m

Deal found 8/26

$281

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 August 28, 2026.

Tue 10/276:00 am -

1 stop7h 08m

Tue 11/312:35 pm -

1 stop10h 40m

Deal found 8/27

$351

Wed 9/301:04 pm -

1 stop7h 39m

Fri 10/25:12 pm -

1 stop8h 12m

Deal found 8/26

$366

Tue 11/104:09 pm -

1 stop10h 35m

Tue 11/177:46 am -

1 stop10h 27m

Deal found 8/24

$399

Wed 10/281:35 pm -

1 stop7h 00m

Sun 11/16:00 am -

1 stop8h 06m

Deal found 8/25

$376

Thu 9/101:53 pm -

1 stop8h 04m

Sun 9/136:30 am -

1 stop9h 20m

Deal found 8/23

$423

Fri 10/301:35 pm -

1 stop7h 00m

Sun 11/16:00 am -

1 stop8h 06m

Deal found 8/24

$391

Thu 12/1012:00 pm -

1 stop8h 59m

Thu 12/317:00 am -

1 stop11h 05m

Deal found 8/26

$459

Thu 10/221:52 pm -

1 stop8h 14m

Thu 10/294:20 pm -

1 stop9h 28m

Deal found 8/23

$429

Wed 12/912:20 pm -

1 stop9h 22m

Fri 12/115:00 pm -

1 stop7h 56m

Deal found 8/27

$399

Mon 12/1412:00 pm -

1 stop8h 59m

Thu 12/317:00 am -

1 stop11h 05m

Deal found 8/27

$461

Wed 10/214:03 pm -

1 stop10h 43m

Wed 11/1112:35 pm -

1 stop8h 26m

Deal found 8/23

$461

Tue 12/16:40 pm -

1 stop9h 48m

Sat 12/512:35 pm -

2 stops10h 45m

Deal found 8/25

$466

Last-minute flights from Ontario to Dulles Intl
Discover last-minute flight deals from Ontario to Dulles Intl. Data last updated August 28, 2026 and is based on user searches.

Tue 9/155:44 pm -

1 stop9h 36m

Tue 9/299:04 pm -

2 stops29h 43m

Deal found 8/28

$272

Thu 9/178:24 pm -

1 stop6h 56m

Sat 9/196:00 am -

1 stop28h 04m

Deal found 8/26

$285

Sat 9/1910:04 am -

1 stop17h 16m

Sat 9/2612:30 pm -

1 stop7h 16m

Deal found 8/27

$262

Tue 9/225:44 pm -

1 stop9h 36m

Tue 9/299:04 pm -

2 stops29h 43m

Deal found 8/27

$271

Tue 9/225:44 pm -

1 stop9h 36m

Thu 10/112:30 pm -

1 stop9h 09m

Deal found 8/24

$279

Wed 9/232:30 pm -

1 stop12h 50m

Wed 9/307:50 am -

2 stops18h 57m

Deal found 8/27

$280

Thu 9/248:24 pm -

1 stop6h 56m

Tue 9/296:00 am -

1 stop13h 59m

Deal found 8/28

$261

Thu 9/248:24 pm -

1 stop6h 56m

Wed 9/307:50 am -

2 stops18h 57m

Deal found 8/26

$274

Fri 9/258:24 pm -

1 stop6h 56m

Thu 10/112:30 pm -

1 stop9h 09m

Deal found 8/26

$277

Fri 9/258:24 pm -

1 stop6h 56m

Mon 10/56:00 am -

1 stop8h 22m

Deal found 8/24

$286

Sat 9/2610:04 am -

1 stop17h 16m

Sat 10/312:30 pm -

1 stop7h 16m

Deal found 8/24

$283

Mon 9/288:24 pm -

1 stop6h 56m

Mon 10/129:06 pm -

2 stops29h 44m

Deal found 8/26

$275

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 August 28, 2026.

Thu 9/248:24 pm -

1 stop6h 56m

Deal found 8/27

$124

Tue 9/155:44 pm -

1 stop9h 36m

Deal found 8/25

$125

Thu 9/178:24 pm -

1 stop6h 56m

Deal found 8/27

$126

Mon 10/198:35 pm -

1 stop6h 45m

Deal found 8/27

$129

Wed 9/237:11 pm -

1 stop13h 22m

Deal found 8/27

$130

Sat 9/192:30 pm -

1 stop12h 50m

Deal found 8/26

$132

Mon 10/128:03 pm -

1 stop12h 31m

Deal found 8/27

$134

Tue 10/1311:26 am -

1 stop15h 54m

Deal found 8/25

$135

Sat 9/1211:45 am -

2 stops15h 35m

Deal found 8/23

$140

Find flight deals from Ontario to Dulles Intl

Most accurate provider	FlightHub 3 stars
Most trusted provider	FlightHub 3 stars
Round-trip from	$259 (Trip.com)
One-way from	$124 (Super.com)
Popular in	April
Cheapest in	September
Average price	$643

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. 8% potential increase in price ($52 potential increase over avg. RT price).

Search Deals

Cheapest flight prices on average. 6% potential price decrease ($37 potential savings vs. average RT price).

Search Deals

Average for round-trip flights in August 2026

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

Cheapest round-trip

OntarioWashington, D.C.

ONT Ontario - IAD Washington, D.C. Dulles Intl

ONTIAD

Ontario

Tue 10/27

6:00 am-4:08 pm

1 stop7h 08m

Washington, D.C. Dulles Intl

Tue 11/3

12:35 pm-8:15 pm

1 stop10h 40m

$351

OntarioWashington, D.C.

ONT Ontario - IAD Washington, D.C. Dulles Intl

ONTIAD

Ontario

Wed 9/30

1:04 pm-11:43 pm

1 stop7h 39m

Washington, D.C. Dulles Intl

Fri 10/2

5:12 pm-10:24 pm

1 stop8h 12m

$366

Quickest round-trip

OntarioWashington, D.C.

ONT Ontario - IAD Washington, D.C. Dulles Intl

ONTIAD

Ontario

Wed 10/28

1:35 pm-11:35 pm

1 stop7h 00m

Washington, D.C. Dulles Intl

Sun 11/1

6:00 am-11:06 am

1 stop8h 06m

$376

OntarioWashington, D.C.

ONT Ontario - IAD Washington, D.C. Dulles Intl

ONTIAD

Ontario

Fri 10/30

1:35 pm-11:35 pm

1 stop7h 00m

Washington, D.C. Dulles Intl

Sun 11/1

6:00 am-11:06 am

1 stop8h 06m

$391

OntarioWashington, D.C.

ONT Ontario - IAD Washington, D.C. Dulles Intl

ONTIAD

Ontario

Tue 11/10

4:09 pm-5:44 am

1 stop10h 35m

Washington, D.C. Dulles Intl

Tue 11/17

7:46 am-3:13 pm

1 stop10h 27m

$399

OntarioWashington, D.C.

ONT Ontario - IAD Washington, D.C. Dulles Intl

ONTIAD

Ontario

Wed 12/9

12:20 pm-12:42 am

1 stop9h 22m

Washington, D.C. Dulles Intl

Fri 12/11

5:00 pm-9:56 pm

1 stop7h 56m

$399

OntarioWashington, D.C.

ONT Ontario - IAD Washington, D.C. Dulles Intl

ONTIAD

Ontario

Thu 9/10

1:53 pm-12:57 am

1 stop8h 04m

Washington, D.C. Dulles Intl

Sun 9/13

6:30 am-12:50 pm

1 stop9h 20m

$423

OntarioWashington, D.C.

ONT Ontario - IAD Washington, D.C. Dulles Intl

ONTIAD

Ontario

Thu 10/22

1:52 pm-1:06 am

1 stop8h 14m

Washington, D.C. Dulles Intl

Thu 10/29

4:20 pm-10:48 pm

1 stop9h 28m

$429

OntarioWashington, D.C.

ONT Ontario - IAD Washington, D.C. Dulles Intl

ONTIAD

Ontario

Thu 12/10

12:00 pm-11:59 pm

1 stop8h 59m

Washington, D.C. Dulles Intl

Thu 12/31

7:00 am-3:05 pm

1 stop11h 05m

$459

OntarioWashington, D.C.

ONT Ontario - IAD Washington, D.C. Dulles Intl

ONTIAD

Ontario

Mon 12/14

12:00 pm-11:59 pm

1 stop8h 59m

Washington, D.C. Dulles Intl

Thu 12/31

7:00 am-3:05 pm

1 stop11h 05m

$461

Flights are sorted by cheapest round-trip flights first.

Deals found on 8/23

Showing 1-10 of 24 resultsSorted by cheapest first

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 August.

Provider	Price Accuracy	Trust Score*
Expedia	Price Accuracy1 star	Trust Score*3 stars
FlightHub	Price Accuracy3 stars	Trust Score*3 stars
CheapOair	Price Accuracy3 stars	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 FlightHub to be most consistent on Cheapflights vs. FlightHub Users can find the same prices on Ontario-Washington, D.C. Dulles Intl Airport flight deals on Cheapflights vs. FlightHub >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 FlightHub the most. FlightHub 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.

ONT-IAD

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

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

Currently, September is the cheapest month in which you can book a flight from Ontario to Washington, D.C. Dulles Intl Airport (average of $365). Flying from Ontario to Washington, D.C. Dulles Intl Airport in April is currently the most expensive (average of $984). 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.

How much does it cost to fly round-trip from Ontario to Washington, D.C. Dulles Intl Airport?

Airfare is below average for this route at the moment.

Ontario to Washington, D.C. Dulles Intl Airport flights typically cost between $284 and $412 in October.
The cheapest round-trip price found within the last 5 days was $259 on Frontier (Oct 15-Oct 22).

Reviews of airlines servicing Dulles Intl

Read reviews from past customers who have flown Southwest,Delta, andUnited 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

4,203 reviews

Reviews

1 / 20

8.0

Excellent

La Tracimeldamarcos,Jun 2026

LAX - SLC

The second flight was not as comfortable as the first as we had to change planes to what seemed to be a slightly older aircraft. The seats weren’t as comfortable as the other plane. But it wasn’t bad.

Southwest

8.0

Very good

4,203 reviews

Southwest

8.0

Very good

4,203 reviews

Reviews

1 / 20

8.0

Excellent

La Tracimeldamarcos,Jun 2026

LAX - SLC

Delta

7.8

Good

8,535 reviews

Southwest

8.0

Very good

4,203 reviews

Reviews

1 / 20

8.0

Excellent

La Tracimeldamarcos,Jun 2026

LAX - SLC

United Airlines

7.4

Good

10,135 reviews

Southwest

8.0

Very good

4,203 reviews

Reviews

1 / 20

8.0

Excellent

La Tracimeldamarcos,Jun 2026

LAX - SLC

American Airlines

7.1

Good

12,022 reviews

Southwest

8.0

Very good

4,203 reviews

Reviews

1 / 20

8.0

Excellent

La Tracimeldamarcos,Jun 2026

LAX - SLC

Frontier

5.6

Fair

2,639 reviews

Southwest

8.0

Very good

4,203 reviews

Reviews

1 / 20

8.0

Excellent

La Tracimeldamarcos,Jun 2026

LAX - SLC

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 United Airlines and Delta fly from Ontario to Washington, D.C. Dulles Intl Airport in about 7h 08m. The time it takes to get you to your destination can typically vary by up to 31m. 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 $105. Other airlines that can offer you cheap pricing are American Airlines, from $256, and Southwest, from $318. Users have found that Frontier is 82% 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 $141. American Airlines flights start at $159 while deals on Delta start at $160 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, September is the cheapest month in which you can book a flight from Ontario to Washington, D.C. Dulles Intl Airport (average of $365). Flying from Ontario to Washington, D.C. Dulles Intl Airport in April is currently the most expensive (average of $984). 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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Herndon

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Palm Springs to Baltimore flights

Top 5 airlines flying from Ontario to Dulles Intl

Airline	Cheapest	Average	Flexibility	On-time
Frontier	Cheapest$105	Average$318	FlexibilityNo cancel fee	On-time62%
American Airlines	Cheapest$256	Average$555	FlexibilityNo cancel fee	On-time71%
Southwest	Cheapest$318	Average$448	FlexibilityNo cancel fee	On-time63%
Delta	Cheapest$318	Average$452	FlexibilityNo cancel fee	On-timeN/A
United Airlines	Cheapest$363	Average$626	FlexibilityNo cancel fee	On-time69%

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$124+ 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 9/24. 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

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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 August 28, 2026.

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 August 28, 2026.

Best flights from Ontario to Dulles IntlDiscover 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 August 28, 2026.

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 August 28, 2026.

Last-minute flights from Ontario to Dulles IntlDiscover last-minute flight deals from Ontario to Dulles Intl. Data last updated August 28, 2026 and is based on user searches.

Discover last-minute flight deals from Ontario to Dulles Intl. Data last updated August 28, 2026 and is based on user searches.

One-way flights from Ontario to Dulles IntlSearch for one-way flight options from Ontario to Dulles Intl. Find affordable one-way fares based on user searches. Data last updated August 28, 2026.

Search for one-way flight options from Ontario to Dulles Intl. Find affordable one-way fares based on user searches. Data last updated August 28, 2026.

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

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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 August.

Best time to book a flight from Ontario to Dulles Intl

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

How much does it cost to fly round-trip from Ontario to Washington, D.C. Dulles Intl Airport?

Airfare is below average for this route at the moment.

Ontario to Washington, D.C. Dulles Intl Airport flights typically cost between $284 and $412 in October.The cheapest round-trip price found within the last 5 days was $259 on Frontier (Oct 15-Oct 22).

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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?

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

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Alternative routes for Ontario to Dulles Intl

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Other flights to Dulles Intl

Explore flights to Dulles Intl departing from other origins. Flights are based on user searches made on Cheapflights and were last updated on August 28, 2026.

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Ontario and Dulles Intl flights

Browse other Ontario and Dulles Intl flight options. Last updated on August 28, 2026.

Other flights from Ontario

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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 August 28, 2026.

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 August 28, 2026.

Last-minute flights from Ontario to Dulles Intl
Discover last-minute flight deals from Ontario to Dulles Intl. Data last updated August 28, 2026 and is based on user searches.

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 August 28, 2026.

Ontario to Washington, D.C. Dulles Intl Airport flights typically cost between $284 and $412 in October.
The cheapest round-trip price found within the last 5 days was $259 on Frontier (Oct 15-Oct 22).