What’s the fastest layover option from Washington, D.C. Dulles Intl Airport to Ontario?

Flights via Denver (DEN) have the shortest average one-way travel time for 1-stop routes: 6h 55m.

Which airport typically offers the quickest layover for flights from Washington, D.C. Dulles Intl Airport to Ontario?

Flights via Denver (DEN) offer the fastest connection on this route, with an average layover time of 0h 50m.

What’s the top layover airport for flights from Washington, D.C. Dulles Intl Airport to Ontario?

Denver (DEN) – chosen by Cheapflights users on 50% of 1-stop itineraries from Washington, D.C. Dulles Intl Airport to Ontario on Cheapflights.

What’s the cheapest layover airport for flights from Washington, D.C. Dulles Intl Airport to Ontario?

Las Vegas (LAS) is the most affordable 1-stop option, with an average round-trip price of $337.

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

For as low as $332, Alaska Airlines can have you in Ontario from Washington, D.C. Dulles Intl Airport in 11h 42m. The distance between Washington, D.C. Dulles Intl Airport and Ontario is about 2236 mi. This flight may include one or multiple stops.

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

Our cheapest airline available from Washington, D.C. Dulles Intl Airport to Ontario is Frontier. Our recent data shows that you can find tickets from as low as $129 on this airline. Additional options worth looking into are Delta and United Airlines, starting at $213 and $284 round-trip. Frontier is priced at 71% lower than the current average price of a flight leaving 3 months from now.

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

The cheapest airline one-way is Frontier, with whom users have recently found tickets for as low as $92. However, be on the lookout for offers from American Airlines and United Airlines, as they are both options that can get you from Washington, D.C. Dulles Intl Airport to Ontario for a low price.

In terms of precipitation, rainfall in Ontario ranges from 0.1 - 3.4 inches per month. February is typically the wettest month, when rainfall can reach 3.4 in. June is typically the driest time to visit Ontario when rainfall is around 0.1 in.

If weather is an important factor for your trip to Ontario, use this chart to help with planning. For those seeking warmer temperatures, August is the ideal time of year to visit, when temperatures reach an average of 78.8 F. Travelers looking to avoid the cold should look outside of December, when temperatures are typically at their lowest (around 53.6 F).

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

United Airlines, Frontier and Southwest are the most popular airlines when flying from Washington, D.C. Dulles Intl Airport to Ontario.

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

Most trusted provider : When it comes to deals on Washington, D.C. Dulles Intl Airport-Ontario 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 Washington, D.C. Dulles Intl Airport-Ontario flight deals. Provider user feedback score is based on Cheapflights searches over the past month and is updated monthly.

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

Ontario (ONT), located 3.1 mi from the city center, is the airport you fly into when you book flights from Washington, D.C. Dulles Intl to Ontario. 5 airlines have flights to Ontario from Washington, D.C. Dulles Intl on a regular basis. Booking flights from Washington, D.C. Dulles Intl to Ontario should not be difficult; the airport handles an average of 0 inbound flights from Washington, D.C. Dulles Intl per day.

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

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

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

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

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

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

$60+ Flights from Washington, D.C. Dulles Intl Airport to Ontario

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Cheap flight deals from Dulles Intl to Ontario

Cheapest flights from Dulles Intl to Ontario
Explore the most affordable flight options available from Dulles Intl to Ontario. Find the lowest fares from popular airlines and budget airlines, with prices last updated on December 3, 2025.

Tue 12/309:58 pmIAD - ONT

2 stops37h 55mFrontier

Thu 1/88:31 amONT - IAD

1 stop9h 25mFrontier

Deal found 12/1

$274

Tue 12/306:05 pmIAD - ONT

1 stop8h 05mSouthwest

Wed 1/75:55 amONT - IAD

1 stop7h 55mSouthwest

Deal found 12/1

$287

Wed 12/319:12 amIAD - ONT

2 stops12h 16mAmerican Airlines

Wed 1/77:16 amONT - IAD

1 stop11h 01mAmerican Airlines

Deal found 12/2

$294

Tue 12/306:05 pmIAD - ONT

1 stop8h 05mSouthwest

Sat 1/105:50 amONT - IAD

1 stop6h 05mSouthwest

Deal found 12/1

$331

Wed 12/176:30 amIAD - ONT

1 stop8h 47mUnited Airlines

Wed 12/2411:59 pmONT - IAD

1 stop8h 49mUnited Airlines

Deal found 12/1

$333

Tue 12/306:05 amIAD - ONT

1 stop8h 48mAmerican Airlines

Tue 1/66:00 amONT - IAD

1 stop12h 17mAmerican Airlines

Deal found 12/1

$335

Wed 12/315:31 pmIAD - ONT

1 stop7h 54mUnited Airlines

Mon 1/55:05 amONT - IAD

1 stop7h 29mUnited Airlines

Deal found 12/1

$368

Best flights from Dulles Intl to Ontario
Discover carefully curated flight deals from Dulles Intl to Ontario that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated December 3, 2025.

Wed 1/286:04 pmIAD - ONT

1 stop24h 04mAlaska Airlines

Tue 2/311:53 amONT - IAD

1 stop25h 33mAlaska Airlines

Deal found 12/2

$264

Sat 1/3112:23 pmIAD - ONT

2 stops11h 42mDelta

Sun 2/157:30 amONT - IAD

1 stop12h 40mDelta

Deal found 12/1

$332

Tue 1/132:24 pmIAD - ONT

1 stop9h 34mUnited Airlines

Sat 1/176:00 amONT - IAD

1 stop10h 35mUnited Airlines

Deal found 12/2

$357

Tue 2/36:04 pmIAD - ONT

1 stop24h 04mAlaska Airlines

Tue 2/104:03 pmONT - IAD

1 stop21h 23mAlaska Airlines

Deal found 12/2

$304

Wed 1/283:42 pmIAD - ONT

1 stop8h 23mDelta

Wed 2/111:10 pmONT - IAD

1 stop7h 38mDelta

Deal found 12/1

$335

Mon 1/126:04 pmIAD - ONT

1 stop29h 32mAlaska Airlines

Sat 1/1711:53 amONT - IAD

1 stop25h 33mAlaska Airlines

Deal found 12/2

$324

Mon 1/264:10 pmIAD - ONT

1 stop9h 43mUnited Airlines

Tue 1/276:00 amONT - IAD

1 stop7h 45mUnited Airlines

Deal found 12/2

$363

Thu 1/87:30 amIAD - ONT

1 stop9h 26mDelta

Wed 1/1412:41 pmONT - IAD

1 stop7h 56mDelta

Deal found 12/1

$342

Mon 1/57:33 amIAD - ONT

1 stop29h 17mAlaska Airlines

Mon 1/124:03 pmONT - IAD

1 stop21h 23mAlaska Airlines

Deal found 12/2

$343

Sat 1/317:30 amIAD - ONT

1 stop18h 21mDelta

Fri 2/1310:20 pmONT - IAD

1 stop8h 34mDelta

Deal found 12/1

$362

Tue 1/136:04 pmIAD - ONT

1 stop29h 32mAlaska Airlines

Tue 1/204:03 pmONT - IAD

1 stop21h 23mAlaska Airlines

Deal found 12/2

$349

Sun 1/256:04 pmIAD - ONT

1 stop19h 55mAlaska Airlines

Fri 1/3011:53 amONT - IAD

1 stop25h 33mAlaska Airlines

Deal found 12/1

$364

Last-minute flights from Dulles Intl to Ontario
Discover last-minute flight deals from Dulles Intl to Ontario. Data last updated December 3, 2025 and is based on user searches.

Tue 1/64:30 pmIAD - ONT

1 stop7h 35mSouthwest

Sat 1/105:50 amONT - IAD

1 stop6h 05mSouthwest

Deal found 12/1

$204

Wed 1/74:30 pmIAD - ONT

1 stop7h 35mSouthwest

Sat 1/105:50 amONT - IAD

1 stop6h 05mSouthwest

Deal found 12/2

$192

Fri 1/96:00 amIAD - ONT

1 stop11h 18mAmerican Airlines

Mon 1/1211:59 pmONT - IAD

1 stop13h 32mAmerican Airlines

Deal found 12/2

$229

Wed 1/219:05 amIAD - ONT

2 stops11h 05mSouthwest

Tue 1/275:55 amONT - IAD

1 stop7h 55mSouthwest

Deal found 12/2

$189

Thu 1/226:00 amIAD - ONT

1 stop11h 18mAmerican Airlines

Tue 1/276:00 amONT - IAD

1 stop7h 31mAmerican Airlines

Deal found 12/2

$191

Thu 1/225:30 pmIAD - ONT

1 stop7h 15mSouthwest

Tue 1/2710:40 amONT - IAD

2 stops8h 15mSouthwest

Deal found 12/3

$212

Wed 1/285:26 pmIAD - ONT

1 stop8h 22mAmerican Airlines

Wed 2/1110:58 amONT - IAD

1 stop7h 19mAmerican Airlines

Deal found 12/2

$169

Wed 1/285:26 pmIAD - ONT

1 stop8h 22mAmerican Airlines

Mon 2/211:59 pmONT - IAD

1 stop18h 18mAmerican Airlines

Deal found 12/1

$184

Fri 1/306:00 amIAD - ONT

1 stop14h 22mAmerican Airlines

Tue 2/106:00 amONT - IAD

1 stop7h 31mAmerican Airlines

Deal found 12/3

$223

One-way flights from Dulles Intl to Ontario
Search for one-way flight options from Dulles Intl to Ontario. Find affordable one-way fares based on user searches. Data last updated December 3, 2025.

Fri 2/2710:49 amIAD - ONT

1 stop10h 12mFrontier

Deal found 12/3

$60

Thu 1/89:59 pmIAD - ONT

1 stop18h 40mFrontier

Deal found 12/3

$63

Sun 1/119:59 pmIAD - ONT

1 stop18h 40mFrontier

Deal found 12/3

$70

Sun 1/2510:50 amIAD - ONT

1 stop8h 36mFrontier

Deal found 12/2

$74

Sun 1/1811:00 amIAD - ONT

1 stop11h 01mFrontier

Deal found 12/1

$81

Tue 1/136:00 amIAD - ONT

2 stops38h 54mFrontier

Deal found 12/2

$84

Wed 1/75:30 pmIAD - ONT

1 stop7h 15mSouthwest

Deal found 12/3

$85

Wed 1/146:00 amIAD - ONT

2 stops40h 01mFrontier

Deal found 12/3

$86

Fri 1/95:41 pmIAD - ONT

2 stops32h 33mFrontier

Deal found 12/2

$89

Tue 1/276:00 amIAD - ONT

2 stops15h 20mAmerican Airlines

Deal found 12/2

$90

Find flight deals from Dulles Intl to Ontario

Most accurate provider	eDreams 3 stars
Most trusted provider	eDreams 3 stars
Round-trip from	$148 (Frontier)
One-way from	$60 (Trip.com)
Popular in	November
Cheapest in	September
Average price	$639

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

Search Deals

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

Search Deals

From Washington, D.C. Dulles Intl to Ontario

Search Deals

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

Search Deals

Highest demand for flights based on searches. 21% potential increase in price ($120 potential increase over avg. RT price).

Search Deals

Cheapest flight prices on average. 4% potential price decrease ($20 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 Washington, D.C. Dulles Intl Airport to Ontario that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

Washington, D.C.Ontario

IAD - ONT

IADONT

Washington, D.C. Dulles Intl

Wed 1/28

6:04 pm-3:08 pm

1 stop24h 04m

Ontario

Tue 2/3

11:53 am-4:26 pm

1 stop25h 33m

$264

Washington, D.C.Ontario

IAD - ONT

IADONT

Washington, D.C. Dulles Intl

Tue 2/3

6:04 pm-3:08 pm

1 stop24h 04m

Ontario

Tue 2/10

4:03 pm-4:26 pm

1 stop21h 23m

$304

Washington, D.C.Ontario

IAD - ONT

IADONT

Washington, D.C. Dulles Intl

Mon 1/12

6:04 pm-8:36 pm

1 stop29h 32m

Ontario

Sat 1/17

11:53 am-4:26 pm

1 stop25h 33m

$324

Washington, D.C.Ontario

IAD - ONT

IADONT

Washington, D.C. Dulles Intl

Sat 1/31

12:23 pm-9:05 pm

2 stops11h 42m

Ontario

Sun 2/15

7:30 am-11:10 pm

1 stop12h 40m

$332

Washington, D.C.Ontario

IAD - ONT

IADONT

Washington, D.C. Dulles Intl

Wed 1/28

3:42 pm-9:05 pm

1 stop8h 23m

Ontario

Wed 2/11

1:10 pm-11:48 pm

1 stop7h 38m

$335

Washington, D.C.Ontario

IAD - ONT

IADONT

Washington, D.C. Dulles Intl

Thu 1/8

7:30 am-1:56 pm

1 stop9h 26m

Ontario

Wed 1/14

12:41 pm-11:37 pm

1 stop7h 56m

$342

Washington, D.C.Ontario

IAD - ONT

IADONT

Washington, D.C. Dulles Intl

Mon 1/5

7:33 am-9:50 am

1 stop29h 17m

Ontario

Mon 1/12

4:03 pm-4:26 pm

1 stop21h 23m

$343

Washington, D.C.Ontario

IAD - ONT

IADONT

Washington, D.C. Dulles Intl

Tue 1/13

6:04 pm-8:36 pm

1 stop29h 32m

Ontario

Tue 1/20

4:03 pm-4:26 pm

1 stop21h 23m

$349

Washington, D.C.Ontario

IAD - ONT

IADONT

Washington, D.C. Dulles Intl

Tue 1/13

2:24 pm-8:58 pm

1 stop9h 34m

Ontario

Sat 1/17

6:00 am-7:35 pm

1 stop10h 35m

$357

Washington, D.C.Ontario

IAD - ONT

IADONT

Washington, D.C. Dulles Intl

Sat 1/31

7:30 am-10:51 pm

1 stop18h 21m

Ontario

Fri 2/13

10:20 pm-9:54 am

1 stop8h 34m

$362

Flights are sorted by cheapest round-trip flights first.

Deals found on 12/1

Showing 1-10 of 24 results

Compare providers for flights from Dulles Intl to Ontario

Use the table below to compare price accuracy, trust ratings, and cancellation policies for each provider offering flight deals from Dulles Intl to Ontario 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
JustAirTicket	Price Accuracy-	Trust Score*1 star

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

Have a flexible travel schedule? Discover the best time to fly to Ontario from Dulles Intl 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 Washington, D.C. Dulles Intl Airport to Ontario

Prices

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

Currently, August is the cheapest month in which you can book a flight from Washington, D.C. Dulles Intl Airport to Ontario (average of $109). Flying from Washington, D.C. Dulles Intl Airport to Ontario in December is currently the most expensive (average of $237). 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 IAD to ONT?

It’s typically best to fly out from Washington, D.C. Dulles Intl Airport to Ontario in the morning. Doing so could potentially save you 29% on the flight price compared to flying at noon, which is usually more expensive.

Reviews of airlines servicing Ontario

Read reviews from past customers who have flown Southwest, Delta, and United Airlines from Washington, D.C. Dulles Intl Airport to Ontario. 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

4,253 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

4,253 reviews

Southwest

8.0

Very good

4,253 reviews

Reviews

1 / 20

8.0

Excellent

Walter,Aug 2025

OAK - SAN

Delta

7.9

Good

8,011 reviews

Southwest

8.0

Very good

4,253 reviews

Reviews

1 / 20

8.0

Excellent

Walter,Aug 2025

OAK - SAN

United Airlines

7.4

Good

9,063 reviews

Southwest

8.0

Very good

4,253 reviews

Reviews

1 / 20

8.0

Excellent

Walter,Aug 2025

OAK - SAN

American Airlines

7.2

Good

11,045 reviews

Southwest

8.0

Very good

4,253 reviews

Reviews

1 / 20

8.0

Excellent

Walter,Aug 2025

OAK - SAN

Frontier

5.8

Fair

3,094 reviews

Southwest

8.0

Very good

4,253 reviews

Reviews

1 / 20

8.0

Excellent

Walter,Aug 2025

OAK - SAN

Related info for your journey

What airport do you fly into for flights to Ontario from Washington, D.C. Dulles Intl?
Ontario (ONT), located 3.1 mi from the city center, is the airport you fly into when you book flights from Washington, D.C. Dulles Intl to Ontario. 5 airlines have flights to Ontario from Washington, D.C. Dulles Intl on a regular basis. Booking flights from Washington, D.C. Dulles Intl to Ontario should not be difficult; the airport handles an average of 0 inbound flights from Washington, D.C. Dulles Intl per day.
How long is the flight from Washington, D.C. Dulles Intl Airport to Ontario?
For as low as $332, Alaska Airlines can have you in Ontario from Washington, D.C. Dulles Intl Airport in 11h 42m. The distance between Washington, D.C. Dulles Intl Airport and Ontario is about 2236 mi. This flight may include one or multiple stops.
What are the cheapest airlines flying from Washington, D.C. Dulles Intl Airport to Ontario round-trip?
Our cheapest airline available from Washington, D.C. Dulles Intl Airport to Ontario is Frontier. Our recent data shows that you can find tickets from as low as $129 on this airline. Additional options worth looking into are Delta and United Airlines, starting at $213 and $284 round-trip. Frontier is priced at 71% lower than the current average price of a flight leaving 3 months from now.
What are the cheapest airlines to fly from Washington, D.C. Dulles Intl Airport to Ontario one-way?
The cheapest airline one-way is Frontier, with whom users have recently found tickets for as low as $92. However, be on the lookout for offers from American Airlines and United Airlines, as they are both options that can get you from Washington, D.C. Dulles Intl Airport to Ontario for a low price.
Can I find deals for flights from Dulles Intl to Ontario that include hotel bookings?
Yes. In addition to deals on Dulles Intl to Ontario flights, Cheapflights offers vacation packages that include both flights and hotel.
How can I find direct flights from Dulles Intl to Ontario?
After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from Dulles Intl to Ontario.
Can I find deals for business class flights from Dulles Intl to Ontario?
Yes. Cheapflights offers flight deals from Dulles Intl to Ontario 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 Washington, D.C. Dulles Intl Airport to Ontario?
Currently, August is the cheapest month in which you can book a flight from Washington, D.C. Dulles Intl Airport to Ontario (average of $109). Flying from Washington, D.C. Dulles Intl Airport to Ontario in December is currently the most expensive (average of $237). 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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Other flights to Ontario

Top 5 airlines flying from Dulles Intl to Ontario

Airline	Cheapest	Average	Flexibility	On-time
Frontier	Cheapest$173	Average$328	FlexibilityNo cancel fee	On-time62%
Delta	Cheapest$213	Average$371	FlexibilityNo cancel fee	On-timeN/A
United Airlines	Cheapest$284	Average$496	FlexibilityNo cancel fee	On-time69%
American Airlines	Cheapest$298	Average$423	FlexibilityNo cancel fee	On-time71%
Southwest	Cheapest$304	Average$576	FlexibilityNo cancel fee	On-time63%

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$60+ Cheap flights from Dulles Intl (IAD) to Ontario (ONT)

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 2/27. Fares are subject to change and may not be available on all flights or dates of travel.

Find cheap flights from Dulles Intl to Ontario with Cheapflights

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Cheap flight deals from Dulles Intl to Ontario

Cheapest flights from Dulles Intl to OntarioExplore the most affordable flight options available from Dulles Intl to Ontario. Find the lowest fares from popular airlines and budget airlines, with prices last updated on December 3, 2025.

Explore the most affordable flight options available from Dulles Intl to Ontario. Find the lowest fares from popular airlines and budget airlines, with prices last updated on December 3, 2025.

Find flight deals from Dulles Intl to Ontario

Most accurate provider

Most trusted provider

Round-trip from

One-way from

Popular in

Cheapest in

Average price

Cheapflights Fare Finder

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

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

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What’s the top layover airport for flights from Washington, D.C. Dulles Intl Airport to Ontario?

What’s the cheapest layover airport for flights from Washington, D.C. Dulles Intl Airport to Ontario?

What’s the fastest layover option from Washington, D.C. Dulles Intl Airport to Ontario?

Which airport typically offers the quickest layover for flights from Washington, D.C. Dulles Intl Airport to Ontario?

Reviews of airlines servicing Ontario

Related info for your journey

Find useful and relevant information for your journey from Dulles Intl to Ontario. 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 into for flights to Ontario from Washington, D.C. Dulles Intl?

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

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

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

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

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

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

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

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Alternative routes for Dulles Intl to Ontario

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Top 5 airlines flying from Dulles Intl to Ontario

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Cheapest flights from Dulles Intl to Ontario
Explore the most affordable flight options available from Dulles Intl to Ontario. Find the lowest fares from popular airlines and budget airlines, with prices last updated on December 3, 2025.