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. The time it takes to get you to your destination can typically vary by up to 3h 37m. 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 $187. Other airlines that can offer you cheap pricing are American Airlines, from $278, and United Airlines, from $292. Users have found that Frontier is 59% cheaper than the other options available to this destination.

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.

$100+ Flights from Ontario to Washington, D.C. Dulles Intl Airport

Q: 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 $411 and $945 in November. The cheapest round-trip price found within the last 3 days was $318 on American Airlines (Nov 15-Nov 19).

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Find cheap flights from Ontario to Dulles Intl with Cheapflights

1. Tell us where you want to go

Enter your travel information like dates, passengers, trip type (one-way or round trip), and preferred cabin class then click “Find deals”

2. Select your favorite providers

We find the providers serving your travel needs. Choose up to four travel providers to compare side-by-side for flights, hotels, or car rentals.

3. Compare prices and book

Review each provider’s pricing and select the best option for you! Book through your favorite provider’s website for a seamless experience.

Cheapflights Tip: The best prices from Ontario to Washington, D.C. Dulles Intl are usually found in July or August, booked 15 days in advance, depart on a Thursday or Saturday and return on a Thursday

Find 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 October 27, 2025.

Sat 11/1510:47 amONT - IAD

1 stop8h 41mAmerican Airlines

Wed 11/196:04 amIAD - ONT

1 stop10h 58mAmerican Airlines

Deal found 10/26

$318

Sat 11/155:49 pmONT - IAD

2 stops13h 35mDelta

Wed 11/197:10 amIAD - ONT

1 stop8h 08mDelta

Deal found 10/26

$324

Wed 11/191:20 pmONT - IAD

1 stop7h 38mDelta

Sun 11/235:59 pmIAD - ONT

1 stop8h 05mDelta

Deal found 10/27

$368

Wed 12/244:36 pmONT - IAD

1 stop10h 37mAlaska Airlines

Thu 1/17:33 amIAD - ONT

1 stop11h 09mAlaska Airlines

Deal found 10/26

$372

Wed 11/199:59 amONT - IAD

2 stops9h 34mAmerican Airlines

Sun 11/234:34 pmIAD - ONT

2 stops10h 23mAmerican Airlines

Deal found 10/27

$378

Wed 12/101:29 pmONT - IAD

1 stop7h 00mDelta

Thu 12/116:00 amIAD - ONT

1 stop8h 02mDelta

Deal found 10/26

$382

Sat 12/67:05 amONT - IAD

1 stop6h 55mDelta

Fri 12/126:00 amIAD - ONT

1 stop8h 02mDelta

Deal found 10/25

$383

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 October 27, 2025.

Wed 12/244:36 pmONT - IAD

1 stop10h 37mAlaska Airlines

Thu 1/17:33 amIAD - ONT

1 stop11h 09mAlaska Airlines

Deal found 10/26

$372

Wed 12/101:29 pmONT - IAD

1 stop7h 00mDelta

Fri 12/126:00 amIAD - ONT

1 stop8h 02mDelta

Deal found 10/25

$382

Thu 12/118:40 amONT - IAD

2 stops10h 20mSouthwest

Wed 12/177:40 amIAD - ONT

1 stop9h 50mSouthwest

Deal found 10/27

$387

Wed 12/35:05 amONT - IAD

1 stop8h 25mUnited Airlines

Sat 12/64:00 pmIAD - ONT

1 stop7h 42mUnited Airlines

Deal found 10/26

$447

Wed 12/244:36 pmONT - IAD

1 stop10h 37mAlaska Airlines

Mon 1/57:33 amIAD - ONT

1 stop11h 09mAlaska Airlines

Deal found 10/26

$372

Tue 1/610:30 pmONT - IAD

1 stop9h 24mDelta

Sun 1/117:30 amIAD - ONT

1 stop17h 59mDelta

Deal found 10/25

$386

Fri 11/144:49 pmONT - IAD

2 stops14h 24mDelta

Wed 11/196:00 amIAD - ONT

1 stop7h 34mDelta

Deal found 10/24

$387

Sun 12/77:05 amONT - IAD

1 stop8h 16mDelta

Fri 12/123:38 pmIAD - ONT

1 stop10h 26mDelta

Deal found 10/27

$417

Fri 12/51:29 pmONT - IAD

1 stop7h 00mDelta

Mon 1/57:00 amIAD - ONT

1 stop11h 20mDelta

Deal found 10/25

$421

Tue 12/21:29 pmONT - IAD

1 stop7h 00mDelta

Sat 12/63:38 pmIAD - ONT

1 stop9h 27mDelta

Deal found 10/25

$435

Last-minute flights from Ontario to Dulles Intl
Discover last-minute flight deals from Ontario to Dulles Intl. Data last updated October 27, 2025 and is based on user searches.

Fri 11/144:49 pmONT - IAD

2 stops14h 24mDelta

Wed 11/196:00 amIAD - ONT

1 stop7h 34mDelta

Deal found 10/24

$387

Fri 11/149:59 amONT - IAD

2 stops10h 08mAmerican Airlines

Wed 11/1911:25 amIAD - ONT

2 stops9h 55mAmerican Airlines

Deal found 10/24

$392

Sat 11/1510:47 amONT - IAD

1 stop8h 41mAmerican Airlines

Wed 11/196:04 amIAD - ONT

1 stop10h 58mAmerican Airlines

Deal found 10/26

$318

Sat 11/155:49 pmONT - IAD

2 stops13h 35mDelta

Wed 11/197:10 amIAD - ONT

1 stop8h 08mDelta

Deal found 10/26

$324

Wed 11/191:20 pmONT - IAD

1 stop7h 38mDelta

Sun 11/235:59 pmIAD - ONT

1 stop8h 05mDelta

Deal found 10/27

$368

Wed 11/199:59 amONT - IAD

2 stops9h 34mAmerican Airlines

Sun 11/234:34 pmIAD - ONT

2 stops10h 23mAmerican Airlines

Deal found 10/26

$378

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 October 27, 2025.

Sun 12/72:59 pmONT - IAD

2 stops23h 26mFrontier

Deal found 10/25

$100

Sat 1/248:30 amONT - IAD

2 stops29h 02mFrontier

Deal found 10/25

$108

Thu 12/410:12 pmONT - IAD

2 stops45h 53mFrontier

Deal found 10/25

$112

Fri 12/56:19 pmONT - IAD

2 stops25h 46mFrontier

Deal found 10/25

$118

Wed 11/198:00 amONT - IAD

2 stops23h 17mFrontier

Deal found 10/25

$119

Tue 11/118:45 amONT - IAD

2 stops32h 35mFrontier

Deal found 10/25

$125

Mon 11/101:46 pmONT - IAD

2 stops27h 34mFrontier

Deal found 10/26

$129

Thu 1/226:56 pmONT - IAD

1 stop11h 58mFrontier

Deal found 10/26

$137

Wed 12/36:15 amONT - IAD

2 stops33h 03mFrontier

Deal found 10/25

$138

Fri 1/96:30 amONT - IAD

3 stops29h 08mMultiple Airlines

Deal found 10/25

$144

Mon 11/246:16 pmONT - IAD

1 stop12h 54mFrontier

Deal found 10/26

$152

Cheap flight deals from Ontario to Dulles Intl

Most accurate provider	eDreams 3 stars
Most trusted provider	eDreams 3 stars
Round-trip from	$318 (American Airlines)
One-way from	$100 (Kiwi.com)
Popular in	November
Cheapest in	July
Average price	$397

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 ($130 potential increase over avg. RT price).

Search Deals

Cheapest flight prices on average. 6% potential price decrease ($28 potential savings vs. average RT price).

Search Deals

Average for round-trip flights in October 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

Wed 12/24

4:36 pm-6:13 am

1 stop10h 37m

Washington, D.C. Dulles Intl

Thu 1/1

7:33 am-3:42 pm

1 stop11h 09m

$372

OntarioWashington, D.C.

ONT - IAD

ONTIAD

Ontario

Wed 12/24

4:36 pm-6:13 am

1 stop10h 37m

Washington, D.C. Dulles Intl

Mon 1/5

7:33 am-3:42 pm

1 stop11h 09m

$372

OntarioWashington, D.C.

ONT - IAD

ONTIAD

Ontario

Wed 12/10

1:29 pm-11:29 pm

1 stop7h 00m

Washington, D.C. Dulles Intl

Fri 12/12

6:00 am-11:02 am

1 stop8h 02m

$382

OntarioWashington, D.C.

ONT - IAD

ONTIAD

Ontario

Tue 1/6

10:30 pm-10:54 am

1 stop9h 24m

Washington, D.C. Dulles Intl

Sun 1/11

7:30 am-10:29 pm

1 stop17h 59m

$386

OntarioWashington, D.C.

ONT - IAD

ONTIAD

Ontario

Thu 12/11

8:40 am-10:00 pm

2 stops10h 20m

Washington, D.C. Dulles Intl

Wed 12/17

7:40 am-2:30 pm

1 stop9h 50m

$387

OntarioWashington, D.C.

ONT - IAD

ONTIAD

Ontario

Fri 11/14

4:49 pm-10:13 am

2 stops14h 24m

Washington, D.C. Dulles Intl

Wed 11/19

6:00 am-10:34 am

1 stop7h 34m

$387

OntarioWashington, D.C.

ONT - IAD

ONTIAD

Ontario

Sun 12/7

7:05 am-6:21 pm

1 stop8h 16m

Washington, D.C. Dulles Intl

Fri 12/12

3:38 pm-11:04 pm

1 stop10h 26m

$417

OntarioWashington, D.C.

ONT - IAD

ONTIAD

Ontario

Fri 12/5

1:29 pm-11:29 pm

1 stop7h 00m

Washington, D.C. Dulles Intl

Mon 1/5

7:00 am-3:20 pm

1 stop11h 20m

$421

OntarioWashington, D.C.

ONT - IAD

ONTIAD

Ontario

Tue 12/2

1:29 pm-11:29 pm

1 stop7h 00m

Washington, D.C. Dulles Intl

Sat 12/6

3:38 pm-10:05 pm

1 stop9h 27m

$435

OntarioWashington, D.C.

ONT - IAD

ONTIAD

Ontario

Wed 12/3

5:05 am-4:30 pm

1 stop8h 25m

Washington, D.C. Dulles Intl

Sat 12/6

4:00 pm-8:42 pm

1 stop7h 42m

$447

Flights are sorted by cheapest round-trip flights first.

Deals found on 10/27

Showing 1-10 of 18 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 October.

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 15 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 $236). 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.

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

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

4,236 reviews

Reviews

1 / 20

8.0

Excellent

Walter,Aug 2025

OAK - SAN

Dozens of flights and I've never seen a row's beverages forgotten. I even went back and asked the attendant to check on them and nothing. I really hope it didn't have something to do with the Black mother with her kid in the row. Otherwise it was a typical Southwest flight, rapid boarding, tolerable leg room.

Southwest

8.0

Very good

4,236 reviews

Southwest

8.0

Very good

4,236 reviews

Reviews

1 / 20

8.0

Excellent

Walter,Aug 2025

OAK - SAN

Delta

7.9

Good

7,996 reviews

Southwest

8.0

Very good

4,236 reviews

Reviews

1 / 20

8.0

Excellent

Walter,Aug 2025

OAK - SAN

United Airlines

7.4

Good

8,997 reviews

Southwest

8.0

Very good

4,236 reviews

Reviews

1 / 20

8.0

Excellent

Walter,Aug 2025

OAK - SAN

American Airlines

7.2

Good

11,033 reviews

Southwest

8.0

Very good

4,236 reviews

Reviews

1 / 20

8.0

Excellent

Walter,Aug 2025

OAK - SAN

Frontier

5.8

Fair

3,122 reviews

Southwest

8.0

Very good

4,236 reviews

Reviews

1 / 20

8.0

Excellent

Walter,Aug 2025

OAK - SAN

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. The time it takes to get you to your destination can typically vary by up to 3h 37m. 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 $187. Other airlines that can offer you cheap pricing are American Airlines, from $278, and United Airlines, from $292. Users have found that Frontier is 59% cheaper than the other options available to this destination.
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 $236). 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$376	FlexibilityNo cancel fee	On-time71%
United Airlines	Cheapest$292	Average$495	FlexibilityNo cancel fee	On-time69%
Southwest	Cheapest$318	Average$463	FlexibilityNo cancel fee	On-time63%
Delta	Cheapest$326	Average$426	FlexibilityNo cancel fee	On-timeN/A

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$100+ 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 12/7. 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

Cheapflights Tip: The best prices from Ontario to Washington, D.C. Dulles Intl are usually found in July or August, booked 15 days in advance, depart on a Thursday or Saturday and return on a Thursday

Find 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 October 27, 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 October 27, 2025.

Cheap 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 October.

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?

How much does it cost to fly round-trip 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?

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?

Browse thousands of different options on Cheapflights for your next trip

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Alternative routes for Ontario to Dulles Intl

See prices for flight routes from nearby airports that may be better suited for you.

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 October 27, 2025.