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Dulles Intl

$90+ 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 5/8. Fares are subject to change and may not be available on all flights or dates of travel.
ONT — IAD
Feb 8 — Feb 151
Sat 2/8
Sat 2/15
1 adult, Economy
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The best prices from Ontario to Washington, D.C. Dulles Intl are usually found in February or August, booked 90 days in advance, depart on a Thursday or Saturday and return on a Thursday

Cheap flight deals from Ontario to Dulles Intl

Discover tips and strategies to find the most affordable flight options for your journey from Ontario (ONT) to Dulles Intl (IAD). Learn about various techniques such as flexible date searches, comparing prices across and setting up price alerts. Use these methods to find the cheapest flights available for your travel needs. Data last updated February 3, 2025.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$262
(Booking.com)

One-way from

$90
(Frontier)

Popular in

December

Cheapest in

February

Average price

$326
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.
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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. 14% potential increase in price ($77 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 2% potential price decrease ($13 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in February 2025
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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 February 3, 2025.

This Booking.com deal was found by Cheapflights users on 2/3. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Booking.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 5/2710:17 pmONT - IAD
1 stop29h 15mFrontier
Sat 5/317:32 amIAD - ONT
1 stop10h 16mFrontier
Deal found 2/3$262
This Delta deal was found by Cheapflights users on 2/3. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 2/151:05 pmONT - IAD
1 stop8h 15mDelta
Sat 2/227:20 amIAD - ONT
1 stop8h 04mDelta
Deal found 2/3$325
This Alaska Airlines deal was found by Cheapflights users on 2/3. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 3/46:00 amONT - IAD
1 stop8h 48mAlaska Airlines
Wed 4/306:30 amIAD - ONT
1 stop12h 02mAlaska Airlines
Deal found 2/3$326
This American Airlines deal was found by Cheapflights users on 2/2. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 3/510:05 amONT - IAD
2 stops9h 28mAmerican Airlines
Tue 3/111:52 pmIAD - ONT
2 stops11h 35mAmerican Airlines
Deal found 2/2$337
This Expedia deal was found by Cheapflights users on 2/2. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 5/86:35 pmONT - IAD
1 stop8h 56mMultiple Airlines
Tue 5/136:30 amIAD - ONT
1 stop12h 02mMultiple Airlines
Deal found 2/2$358
This Southwest deal was found by Cheapflights users on 2/3. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 3/49:00 amONT - IAD
2 stops11h 05mSouthwest
Wed 3/126:45 pmIAD - ONT
1 stop7h 20mSouthwest
Deal found 2/3$368
This United Airlines deal was found by Cheapflights users on 2/2. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 6/146:32 pmONT - IAD
1 stop7h 43mUnited Airlines
Sat 8/238:18 amIAD - ONT
1 stop10h 28mUnited Airlines
Deal found 2/2$397

Find flights from Ontario to Dulles Intl within your budget

Customize your flight search to find flights from Ontario to Dulles Intl that fit within your specific budget. Explore options based on user searches and filter the results based on your desired price range. Find flights that match your budget for a cost-effective journey. Over the last 7 days, Cheapflights users made 2,558,603 searches. Data last updated February 3, 2025.

Fly from

Any airport

Fly to

Any airport

Route

Depart

Return

Price

OntarioWashington, D.C.

ONT - IAD

ONTIAD

Ontario

Tue 5/27

10:17 pm-6:32 am

1 stop29h 15m

Washington, D.C. Dulles Intl

Sat 5/31

7:32 am-2:48 pm

1 stop10h 16m

$262

OntarioWashington, D.C.

ONT - IAD

ONTIAD

Ontario

Sat 2/15

1:05 pm-12:20 am

1 stop8h 15m

Washington, D.C. Dulles Intl

Sat 2/22

7:20 am-12:24 pm

1 stop8h 04m

$325

OntarioWashington, D.C.

ONT - IAD

ONTIAD

Ontario

Tue 3/4

6:00 am-5:48 pm

1 stop8h 48m

Washington, D.C. Dulles Intl

Wed 4/30

6:30 am-3:32 pm

1 stop12h 02m

$326

OntarioWashington, D.C.

ONT - IAD

ONTIAD

Ontario

Fri 2/28

11:59 pm-4:01 pm

2 stops13h 02m

Washington, D.C. Dulles Intl

Mon 3/3

1:48 pm-9:02 pm

1 stop10h 14m

$332

OntarioWashington, D.C.

ONT - IAD

ONTIAD

Ontario

Sat 4/5

10:50 am-12:10 am

2 stops10h 20m

Washington, D.C. Dulles Intl

Wed 4/9

6:40 pm-10:50 pm

1 stop7h 10m

$357

OntarioWashington, D.C.

ONT - IAD

ONTIAD

Ontario

Thu 5/8

6:35 pm-6:31 am

1 stop8h 56m

Washington, D.C. Dulles Intl

Tue 5/13

6:30 am-3:32 pm

1 stop12h 02m

$358

OntarioWashington, D.C.

ONT - IAD

ONTIAD

Ontario

Wed 3/26

1:40 pm-11:23 pm

1 stop6h 43m

Washington, D.C. Dulles Intl

Mon 3/31

2:40 pm-8:21 pm

1 stop8h 41m

$409

OntarioWashington, D.C.

ONT - IAD

ONTIAD

Ontario

Thu 5/8

6:35 pm-6:31 am

1 stop8h 56m

$90

OntarioWashington, D.C.

ONT - IAD

ONTIAD

Ontario

Tue 3/4

6:00 am-5:48 pm

1 stop8h 48m

$163

OntarioWashington, D.C.

ONT - IAD

ONTIAD

Ontario

Mon 4/28

10:40 pm-8:38 am

1 stop6h 58m

$164

Flights are sorted by cheapest round-trip flights first.

Deals found on 2/3

Showing 1-10 of 13 results
1
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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 February.
ProviderPrice AccuracyTrust Score*
ExpediaPrice Accuracy1 starTrust Score*3 stars
FlightHubPrice Accuracy3 starsTrust Score*3 stars
eDreamsPrice Accuracy3 starsTrust Score*3 stars
PricelinePrice Accuracy1 starTrust 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.
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.

Travel insights for flights from Ontario to Dulles Intl

Get recent, data-driven insights about flights from Ontario to Dulles Intl including ideal travel times, pricing trends, and more.

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

Use this chart to determine the optimal time to book a round-trip flight from Ontario to Dulles Intl. Price data was last updated on January 31, 2025.

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 89 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, August is the cheapest month in which you can book a flight from Ontario to Washington, D.C. Dulles Intl Airport (average of $309). Flying from Ontario to Washington, D.C. Dulles Intl Airport in June is currently the most expensive (average of $389). 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?

Find hourly flight availability from Ontario to Dulles Intl. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated February 3, 2025.

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 16% 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?

Use this chart to determine the cheapest time to fly round-trip from Ontario to Dulles Intl. Price data was last updated on December 16, 2024.

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.

Rainfall in Dulles Intl by month

Plan your trip to Dulles Intl by taking into account the average rainfall totals by month.

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.

Temperature in Dulles Intl by month

Plan your trip to Dulles Intl by taking into account the average temperature totals by month.

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).

Reviews of airlines servicing Dulles Intl

Get insights into the airlines that provide service to Dulles Intl. Read reviews, discover amenities, and learn about the overall travel experience offered by airlines. Use this information to make informed decisions when choosing an airline for your flight to Dulles Intl. Reviews last updated February 3, 2025.
Read reviews from past customers who have flown Southwest, Alaska Airlines and Delta from Ontario to Washington, D.C.. You can also see how each airline compares in terms of entertainment options, comfort, food, crew/service, and boarding process.
Southwest
8.1
Very good
4,564 reviews

Entertainment

7.7

Overall

8.1

Comfort

8.1

Food

7.1

Boarding

8.2

Crew

8.7

Reviews

1 / 20

6.0
Good

Lauren,Dec 2024

MCI - DCA

We BARELY made the connection and when we got onboard we were treated like disobedient children who should have arrived earlier because we had to ask other passengers to move so we could sit with our kids. The flight attendants on the first flight were nice but the second one, they were snippy and fairly rude.

Southwest
8.1
Very good
4,564 reviews
Southwest
8.1
Very good
4,564 reviews

Entertainment

7.7

Overall

8.1

Comfort

8.1

Food

7.1

Boarding

8.2

Crew

8.7

Reviews

1 / 20

6.0
Good

Lauren,Dec 2024

MCI - DCA

We BARELY made the connection and when we got onboard we were treated like disobedient children who should have arrived earlier because we had to ask other passengers to move so we could sit with our kids. The flight attendants on the first flight were nice but the second one, they were snippy and fairly rude.

Alaska Airlines
8.0
Very good
9,681 reviews
Southwest
8.1
Very good
4,564 reviews

Entertainment

7.7

Overall

8.1

Comfort

8.1

Food

7.1

Boarding

8.2

Crew

8.7

Reviews

1 / 20

6.0
Good

Lauren,Dec 2024

MCI - DCA

We BARELY made the connection and when we got onboard we were treated like disobedient children who should have arrived earlier because we had to ask other passengers to move so we could sit with our kids. The flight attendants on the first flight were nice but the second one, they were snippy and fairly rude.

Delta
8.0
Very good
8,427 reviews
Southwest
8.1
Very good
4,564 reviews

Entertainment

7.7

Overall

8.1

Comfort

8.1

Food

7.1

Boarding

8.2

Crew

8.7

Reviews

1 / 20

6.0
Good

Lauren,Dec 2024

MCI - DCA

We BARELY made the connection and when we got onboard we were treated like disobedient children who should have arrived earlier because we had to ask other passengers to move so we could sit with our kids. The flight attendants on the first flight were nice but the second one, they were snippy and fairly rude.

United Airlines
7.4
Good
8,889 reviews
Southwest
8.1
Very good
4,564 reviews

Entertainment

7.7

Overall

8.1

Comfort

8.1

Food

7.1

Boarding

8.2

Crew

8.7

Reviews

1 / 20

6.0
Good

Lauren,Dec 2024

MCI - DCA

We BARELY made the connection and when we got onboard we were treated like disobedient children who should have arrived earlier because we had to ask other passengers to move so we could sit with our kids. The flight attendants on the first flight were nice but the second one, they were snippy and fairly rude.

American Airlines
7.2
Good
10,000 reviews
Southwest
8.1
Very good
4,564 reviews

Entertainment

7.7

Overall

8.1

Comfort

8.1

Food

7.1

Boarding

8.2

Crew

8.7

Reviews

1 / 20

6.0
Good

Lauren,Dec 2024

MCI - DCA

We BARELY made the connection and when we got onboard we were treated like disobedient children who should have arrived earlier because we had to ask other passengers to move so we could sit with our kids. The flight attendants on the first flight were nice but the second one, they were snippy and fairly rude.

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?

    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.

  • 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 $262. Other airlines that can offer you cheap pricing are Delta, from $325, and Alaska Airlines, from $326. Users have found that Frontier is 41% 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 $90. Alaska Airlines flights start at $163 while deals on American Airlines start at $164 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, August is the cheapest month in which you can book a flight from Ontario to Washington, D.C. Dulles Intl Airport (average of $309). Flying from Ontario to Washington, D.C. Dulles Intl Airport in June is currently the most expensive (average of $389). 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

Traveling to a place near Ontario?

Book flights to Ontario if you plan to visit one of these locations
Fairfax
Arlington
Alexandria
Springfield
Silver Spring
Rockville
Tysons
Gaithersburg
Fredericksburg
Linthicum Heights
Laurel
Falls Church
Sterling
Easton
Oxon Hill
Herndon
Woodbridge
Bowie
Reston
National Harbor

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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.
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Top 6 airlines flying from Ontario to Dulles Intl

Discover the top 6 airlines that operate flights from Ontario to Dulles Intl. Compare their services, reliability, and customer satisfaction ratings to choose the airline that best suits your travel preferences and needs. Over the last 7 days, Cheapflights users made 2,558,603 searches. Data last updated February 3, 2025.
AirlineCheapestAverageFlexibilityOn-time
Alaska AirlinesCheapest$133Average$216FlexibilityNo cancel feeOn-time75%
FrontierCheapest$153Average$294FlexibilityNo cancel feeOn-time62%
American AirlinesCheapest$256Average$441FlexibilityNo cancel feeOn-time71%
DeltaCheapest$267Average$395FlexibilityNo cancel feeOn-timeN/A
United AirlinesCheapest$279Average$493FlexibilityNo cancel feeOn-time69%
SouthwestCheapest$386Average$518FlexibilityNo cancel feeOn-time63%
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