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

For as low as $351, Alaska Airlines can have you in Ontario from Washington, D.C. Dulles Intl Airport in 8h 06m. 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 $185 on this airline. Additional options worth looking into are Delta and United Airlines, starting at $213 and $269 round-trip. Frontier is priced at 60% 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 $84. However, be on the lookout for offers from Southwest and Delta, 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, American Airlines and Frontier are the most popular airlines when flying from Washington, D.C. Dulles Intl Airport to Ontario.

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

When flying from Washington, D.C. Dulles Intl Airport to Ontario, the time of day you decide to fly out makes little to no difference towards the overall price you’ll pay on tickets.

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

$173+ Cheap Flights from Washington, D.C. Dulles Intl Airport to Ontario

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Cheap flight deals from Dulles Intl to Ontario

Cheapest

Best

Last-minute

One-way

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 September 3, 2026.

Wed 9/306:00 am -

1 stop13h 59m

Wed 10/72:30 pm -

1 stop12h 50m

Deal found 9/2

$252

Thu 9/2412:30 pm -

1 stop9h 09m

Wed 9/302:30 pm -

1 stop12h 50m

Deal found 9/2

$253

Sat 10/312:30 pm -

1 stop7h 16m

Sat 10/105:25 pm -

1 stop9h 55m

Deal found 9/1

$254

Thu 9/2412:30 pm -

1 stop9h 09m

Tue 9/295:44 pm -

1 stop9h 36m

Deal found 9/2

$261

Thu 10/156:00 am -

1 stop11h 34m

Tue 10/205:25 pm -

1 stop9h 55m

Deal found 9/1

$262

Fri 10/1612:30 pm -

1 stop9h 38m

Mon 10/198:03 pm -

1 stop12h 31m

Deal found 9/2

$277

Fri 9/2512:30 pm -

1 stop9h 09m

Thu 10/17:46 pm -

1 stop12h 47m

Deal found 9/2

$278

Sat 9/2612:30 pm -

1 stop7h 16m

Wed 9/3010:04 am -

1 stop17h 16m

Deal found 9/2

$285

Sat 10/176:00 am -

1 stop13h 30m

Mon 10/262:28 pm -

1 stop12h 52m

Deal found 9/2

$287

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 September 3, 2026.

Wed 10/147:02 am -

1 stop9h 14m

Wed 10/2811:13 am -

1 stop9h 46m

Deal found 8/29

$351

Thu 10/156:00 am -

1 stop8h 06m

Mon 10/1911:08 pm -

1 stop7h 11m

Deal found 9/2

$351

Sat 11/74:10 pm -

1 stop7h 41m

Wed 11/111:29 pm -

1 stop6h 46m

Deal found 9/2

$461

Sat 9/267:00 am -

1 stop10h 16m

Wed 10/711:13 am -

1 stop9h 46m

Deal found 8/30

$351

Thu 10/156:00 am -

1 stop8h 06m

Wed 10/281:35 pm -

1 stop7h 00m

Deal found 8/29

$401

Fri 10/235:33 pm -

1 stop9h 09m

Mon 10/262:13 pm -

1 stop12h 27m

Deal found 8/29

$401

Fri 10/307:02 am -

1 stop9h 14m

Tue 11/34:09 pm -

1 stop10h 35m

Deal found 9/2

$401

Mon 11/236:00 am -

1 stop8h 08m

Thu 11/267:00 am -

1 stop9h 54m

Deal found 9/1

$475

Mon 11/237:00 am -

1 stop11h 05m

Fri 12/412:00 pm -

1 stop8h 59m

Deal found 8/31

$406

Fri 9/253:15 pm -

1 stop10h 09m

Sun 9/2710:00 pm -

1 stop8h 09m

Deal found 9/2

$505

Thu 10/227:02 am -

1 stop9h 14m

Sun 10/255:45 pm -

2 stops27h 14m

Deal found 8/29

$502

Last-minute flights from Dulles Intl to Ontario
Discover last-minute flight deals from Dulles Intl to Ontario. Data last updated September 3, 2026 and is based on user searches.

Thu 9/2412:30 pm -

1 stop9h 09m

Wed 9/302:30 pm -

1 stop12h 50m

Deal found 9/2

$253

Thu 9/2412:30 pm -

1 stop9h 09m

Tue 9/295:44 pm -

1 stop9h 36m

Deal found 9/2

$261

Fri 9/2512:30 pm -

1 stop9h 09m

Thu 10/17:46 pm -

1 stop12h 47m

Deal found 9/2

$278

Sat 9/2612:30 pm -

1 stop7h 16m

Wed 9/3010:04 am -

1 stop17h 16m

Deal found 9/2

$285

Wed 9/306:00 am -

1 stop13h 59m

Wed 10/72:30 pm -

1 stop12h 50m

Deal found 9/2

$252

Sat 10/312:30 pm -

1 stop7h 16m

Sat 10/105:25 pm -

1 stop9h 55m

Deal found 9/1

$254

Thu 10/156:00 am -

1 stop11h 34m

Tue 10/205:25 pm -

1 stop9h 55m

Deal found 9/1

$262

Fri 10/1612:30 pm -

1 stop9h 38m

Mon 10/198:03 pm -

1 stop12h 31m

Deal found 9/2

$277

Sat 10/176:00 am -

1 stop13h 30m

Mon 10/262:28 pm -

1 stop12h 52m

Deal found 9/2

$287

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 September 3, 2026.

Sun 9/279:04 pm -

2 stops23h 44m

Deal found 9/2

$173

Sat 10/312:30 pm -

1 stop7h 16m

Deal found 8/31

$175

Wed 10/147:02 am -

1 stop9h 14m

Deal found 9/2

$176

Mon 9/216:00 am -

1 stop8h 22m

Deal found 8/31

$178

Wed 9/306:00 am -

1 stop28h 04m

Deal found 8/31

$181

Wed 9/236:00 am -

1 stop13h 59m

Deal found 8/30

$184

Thu 10/17:50 am -

2 stops18h 57m

Deal found 9/1

$186

Fri 10/97:13 pm -

1 stop7h 39m

Deal found 8/31

$191

Wed 10/219:06 pm -

2 stops16h 23m

Deal found 9/1

$193

Sun 9/206:00 am -

1 stop8h 22m

Deal found 8/30

$194

Fri 10/912:30 pm -

1 stop9h 38m

Deal found 8/31

$197

Thu 11/261:09 pm -

1 stop9h 27m

Deal found 9/2

$198

Find flight deals from Dulles Intl to Ontario

Most accurate provider	FlightHub 3 stars
Most trusted provider	FlightHub 3 stars
Round-trip from	$252 (Frontier)
One-way from	$173 (Kiwi.com)
Popular in	April
Cheapest in	October
Average price	$350

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. 28% potential increase in price ($192 potential increase over avg. RT price).

Search Deals

Cheapest flight prices on average. 9% potential price decrease ($41 potential savings vs. average RT price).

Search Deals

Average for round-trip flights in September 2026

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

Cheapest round-trip

Washington, D.C.Ontario

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

IADONT

Washington, D.C. Dulles Intl

Wed 10/14

7:02 am-1:16 pm

1 stop9h 14m

Ontario

Wed 10/28

11:13 am-11:59 pm

1 stop9h 46m

$351

Washington, D.C.Ontario

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

IADONT

Washington, D.C. Dulles Intl

Thu 10/15

6:00 am-11:06 am

1 stop8h 06m

Ontario

Mon 10/19

11:08 pm-9:19 am

1 stop7h 11m

$351

Washington, D.C.Ontario

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

IADONT

Washington, D.C. Dulles Intl

Sat 9/26

7:00 am-2:16 pm

1 stop10h 16m

Ontario

Wed 10/7

11:13 am-11:59 pm

1 stop9h 46m

$351

Washington, D.C.Ontario

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

IADONT

Washington, D.C. Dulles Intl

Thu 10/15

6:00 am-11:06 am

1 stop8h 06m

Ontario

Wed 10/28

1:35 pm-11:35 pm

1 stop7h 00m

$401

Washington, D.C.Ontario

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

IADONT

Washington, D.C. Dulles Intl

Fri 10/23

5:33 pm-11:42 pm

1 stop9h 09m

Ontario

Mon 10/26

2:13 pm-5:40 am

1 stop12h 27m

$401

Washington, D.C.Ontario

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

IADONT

Washington, D.C. Dulles Intl

Fri 10/30

7:02 am-1:16 pm

1 stop9h 14m

Ontario

Tue 11/3

4:09 pm-5:44 am

1 stop10h 35m

$401

Washington, D.C.Ontario

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

IADONT

Washington, D.C. Dulles Intl

Mon 11/23

7:00 am-3:05 pm

1 stop11h 05m

Ontario

Fri 12/4

12:00 pm-11:59 pm

1 stop8h 59m

$406

Quickest round-trip

Washington, D.C.Ontario

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

IADONT

Washington, D.C. Dulles Intl

Sat 11/7

4:10 pm-8:51 pm

1 stop7h 41m

Ontario

Wed 11/11

1:29 pm-11:15 pm

1 stop6h 46m

$461

Washington, D.C.Ontario

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

IADONT

Washington, D.C. Dulles Intl

Mon 11/23

6:00 am-11:08 am

1 stop8h 08m

Ontario

Thu 11/26

7:00 am-7:54 pm

1 stop9h 54m

$475

Washington, D.C.Ontario

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

IADONT

Washington, D.C. Dulles Intl

Thu 10/22

7:02 am-1:16 pm

1 stop9h 14m

Ontario

Sun 10/25

5:45 pm-11:59 pm

2 stops27h 14m

$502

Flights are sorted by cheapest round-trip flights first.

Deals found on 8/29

Showing 1-10 of 23 resultsSorted by cheapest first

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 September.

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

IAD-ONT

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

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

Currently, October is the cheapest month in which you can book a flight from Washington, D.C. Dulles Intl Airport to Ontario (average of $320). Flying from Washington, D.C. Dulles Intl Airport to Ontario in April is currently the most expensive (average of $917). 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 Washington, D.C. Dulles Intl Airport to Ontario?

Airfare is below average for this route at the moment.

Washington, D.C. Dulles Intl Airport to Ontario flights typically cost between $273 and $444 in September.
The cheapest round-trip price found within the last 5 days was $252 on Frontier (Sep 30-Oct 7).

Reviews of airlines servicing Ontario

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

4,198 reviews

Reviews

1 / 20

10.0

Excellent

Walter,May 2026

LAS - BUR

Short but excellent flight. Everyone was friendly and professional it was a great flight!

Southwest

8.0

Very good

4,198 reviews

Southwest

8.0

Very good

4,198 reviews

Reviews

1 / 20

10.0

Excellent

Walter,May 2026

LAS - BUR

Short but excellent flight. Everyone was friendly and professional it was a great flight!

Delta

7.8

Good

8,549 reviews

Southwest

8.0

Very good

4,198 reviews

Reviews

1 / 20

10.0

Excellent

Walter,May 2026

LAS - BUR

Short but excellent flight. Everyone was friendly and professional it was a great flight!

United Airlines

7.4

Good

10,159 reviews

Southwest

8.0

Very good

4,198 reviews

Reviews

1 / 20

10.0

Excellent

Walter,May 2026

LAS - BUR

Short but excellent flight. Everyone was friendly and professional it was a great flight!

American Airlines

7.1

Good

12,029 reviews

Southwest

8.0

Very good

4,198 reviews

Reviews

1 / 20

10.0

Excellent

Walter,May 2026

LAS - BUR

Short but excellent flight. Everyone was friendly and professional it was a great flight!

Frontier

5.6

Fair

2,627 reviews

Southwest

8.0

Very good

4,198 reviews

Reviews

1 / 20

10.0

Excellent

Walter,May 2026

LAS - BUR

Short but excellent flight. Everyone was friendly and professional it was a great flight!

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 $351, Alaska Airlines can have you in Ontario from Washington, D.C. Dulles Intl Airport in 8h 06m. 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 $185 on this airline. Additional options worth looking into are Delta and United Airlines, starting at $213 and $269 round-trip. Frontier is priced at 60% 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 $84. However, be on the lookout for offers from Southwest and Delta, 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, October is the cheapest month in which you can book a flight from Washington, D.C. Dulles Intl Airport to Ontario (average of $320). Flying from Washington, D.C. Dulles Intl Airport to Ontario in April is currently the most expensive (average of $917). 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.

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Baltimore to San Luis Obispo flights

Top 5 airlines flying from Dulles Intl to Ontario

Airline	Cheapest	Average	Flexibility	On-time
Frontier	Cheapest$185	Average$414	FlexibilityNo cancel fee	On-time62%
Delta	Cheapest$213	Average$397	FlexibilityNo cancel fee	On-timeN/A
United Airlines	Cheapest$269	Average$475	FlexibilityNo cancel fee	On-time69%
Southwest	Cheapest$291	Average$417	FlexibilityNo cancel fee	On-time63%
American Airlines	Cheapest$350	Average$445	FlexibilityNo cancel fee	On-time71%

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$173+ 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 9/27. 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 September 3, 2026.

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 September 3, 2026.

Best flights from Dulles Intl to OntarioDiscover 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 September 3, 2026.

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 September 3, 2026.

Last-minute flights from Dulles Intl to OntarioDiscover last-minute flight deals from Dulles Intl to Ontario. Data last updated September 3, 2026 and is based on user searches.

Discover last-minute flight deals from Dulles Intl to Ontario. Data last updated September 3, 2026 and is based on user searches.

One-way flights from Dulles Intl to OntarioSearch for one-way flight options from Dulles Intl to Ontario. Find affordable one-way fares based on user searches. Data last updated September 3, 2026.

Search for one-way flight options from Dulles Intl to Ontario. Find affordable one-way fares based on user searches. Data last updated September 3, 2026.

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

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

Compare providers for flights from Dulles Intl to Ontario

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 Dulles Intl to Ontario in September.

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.

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

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

Airfare is below average for this route at the moment.

Washington, D.C. Dulles Intl Airport to Ontario flights typically cost between $273 and $444 in September.The cheapest round-trip price found within the last 5 days was $252 on Frontier (Sep 30-Oct 7).

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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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Other flights to Ontario

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Dulles Intl and Ontario flights

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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 September 3, 2026.

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 September 3, 2026.

Last-minute flights from Dulles Intl to Ontario
Discover last-minute flight deals from Dulles Intl to Ontario. Data last updated September 3, 2026 and is based on user searches.

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 September 3, 2026.

Washington, D.C. Dulles Intl Airport to Ontario flights typically cost between $273 and $444 in September.
The cheapest round-trip price found within the last 5 days was $252 on Frontier (Sep 30-Oct 7).