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Washington, D.C.

$116+ Cheap flights from Ontario (ONT) to Washington, D.C. (WAS)

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 8/11. Fares are subject to change and may not be available on all flights or dates of travel.
ONT — WAS
Jul 29 — Aug 51
Wed 7/29
Wed 8/5
1 adult, Economy
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Find cheap flights from Ontario to Washington, D.C. with Cheapflights

1. Tell us where you want to go

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Cheap flight deals from Ontario to Washington, D.C.

Cheapest flights from Ontario to Washington, D.C.
Explore the most affordable flight options available from Ontario to Washington, D.C.. Find the lowest fares from popular airlines and budget airlines, with prices last updated on June 29, 2026.

This Expedia deal was found by Cheapflights users on 6/24. 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.
Wed 8/129:36 am
ONT
-
BWI
1 stop7h 58m
Frontier
Tue 8/181:24 pm
BWI
-
ONT
1 stop8h 37m
Frontier
Deal found 6/24$240
This Expedia deal was found by Cheapflights users on 6/24. 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.
Mon 7/209:32 am
ONT
-
BWI
1 stop8h 04m
Frontier
Wed 7/224:44 pm
BWI
-
ONT
1 stop17h 48m
Frontier
Deal found 6/24$242
This Frontier deal was found by Cheapflights users on 6/26. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 8/179:36 am
ONT
-
BWI
1 stop7h 58m
Frontier
Tue 8/251:24 pm
BWI
-
ONT
1 stop8h 37m
Frontier
Deal found 6/26$244
This Frontier deal was found by Cheapflights users on 6/24. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 8/79:36 am
ONT
-
BWI
1 stop8h 03m
Frontier
Wed 8/191:24 pm
BWI
-
ONT
1 stop8h 37m
Frontier
Deal found 6/24$246
This Frontier deal was found by Cheapflights users on 6/29. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 8/169:36 am
ONT
-
BWI
1 stop7h 58m
Frontier
Wed 8/191:24 pm
BWI
-
ONT
1 stop8h 37m
Frontier
Deal found 6/29$247
This Booking.com deal was found by Cheapflights users on 6/24. 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.
Wed 8/59:36 am
ONT
-
BWI
1 stop7h 58m
Frontier
Mon 8/104:44 pm
BWI
-
ONT
1 stop17h 48m
Frontier
Deal found 6/24$248
This Booking.com deal was found by Cheapflights users on 6/28. 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.
Mon 8/179:36 am
ONT
-
BWI
1 stop7h 58m
Frontier
Thu 8/201:24 pm
BWI
-
ONT
1 stop21h 08m
Frontier
Deal found 6/28$249
This Booking.com deal was found by Cheapflights users on 6/25. 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.
Sat 7/259:32 am
ONT
-
BWI
1 stop8h 04m
Frontier
Mon 7/274:44 pm
BWI
-
ONT
1 stop17h 48m
Frontier
Deal found 6/25$250
This Gotogate deal was found by Cheapflights users on 6/24. 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 Gotogate is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 8/69:36 am
ONT
-
BWI
1 stop7h 58m
Frontier
Fri 8/144:44 pm
BWI
-
ONT
1 stop17h 48m
Frontier
Deal found 6/24$251
This CheapOair deal was found by Cheapflights users on 6/24. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 7/279:32 am
ONT
-
BWI
1 stop8h 04m
Frontier
Thu 7/304:44 pm
BWI
-
ONT
1 stop17h 48m
Frontier
Deal found 6/24$252
This Mytrip deal was found by Cheapflights users on 6/26. 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 Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 8/149:36 am
ONT
-
BWI
1 stop7h 58m
Frontier
Thu 8/201:24 pm
BWI
-
ONT
1 stop21h 08m
Frontier
Deal found 6/26$253
This CheapOair deal was found by Cheapflights users on 6/24. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 7/116:00 am
ONT
-
DCA
1 stop7h 59m
Frontier
Sat 7/186:00 pm
DCA
-
ONT
1 stop19h 04m
Frontier
Deal found 6/24$315

Find flight deals from Ontario to Washington, D.C.

Discover tips and strategies to find the most affordable flight options for your journey from Ontario (ONT) to Washington, D.C. (WAS). 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 June 29, 2026.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$240
(Expedia)

One-way from

$116
(Trip.com)

Popular in

December

Cheapest in

September

Average price

$527

Good round-trip deal

$497 or less

Good one-way deal

$193 or less
Provider with most accurate pricing for Ontario-Washington, D.C. (WAS) flight deals.
Search Deals
Provider most trusted by Cheapflights users for Ontario-Washington, D.C. (WAS) flights.
Search Deals
From Ontario to Washington, D.C. (WAS)
Search Deals
One-way flight from Ontario to Washington, D.C. (WAS)
Search Deals
Highest demand for flights based on searches. 10% potential increase in price ($48 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 5% potential price decrease ($20 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in June 2026
Search Deals
Price to beat on a round-trip flight from Ontario to Washington, D.C. (WAS).
Search Deals
Price to beat on a one-way flight from Ontario to Washington, D.C. (WAS).
Search Deals

Cheapflights Fare Finder

 
Customize your flight search to find flights from Ontario to Washington, D.C. 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 June 29, 2026.
Use the filters below to find and compare flights from Ontario to Washington, D.C. that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

Cheapest round-trip

OntarioBaltimore

ONT - BWI

ONTBWI

Ontario

Tue 8/4

4:45 pm-6:35 am

2 stops10h 50m

Baltimore/Washington

Tue 8/11

5:40 pm-10:05 pm

1 stop7h 25m

$312

OntarioWashington, D.C.

ONT - IAD

ONTIAD

Ontario

Mon 7/20

10:00 pm-9:26 am

1 stop8h 26m

Washington, D.C. Dulles Intl

Sun 8/23

7:00 am-12:16 pm

1 stop8h 16m

$366

OntarioWashington, D.C.

ONT - DCA

ONTDCA

Ontario

Fri 9/25

7:00 am-5:08 pm

1 stop7h 08m

Washington, D.C. Reagan-National

Mon 9/28

5:10 pm-10:49 pm

1 stop8h 39m

$382

OntarioWashington, D.C.

ONT - IAD

ONTIAD

Ontario

Sun 8/16

10:00 pm-9:20 am

1 stop8h 20m

Washington, D.C. Dulles Intl

Sat 9/12

7:00 am-12:14 pm

1 stop8h 14m

$419

OntarioWashington, D.C.

ONT - IAD

ONTIAD

Ontario

Thu 8/13

1:06 pm-11:39 pm

1 stop7h 33m

Washington, D.C. Dulles Intl

Thu 8/20

3:03 pm-9:52 pm

1 stop9h 49m

$420

OntarioWashington, D.C.

ONT - IAD

ONTIAD

Ontario

Thu 8/6

1:18 pm-12:45 am

1 stop8h 27m

Washington, D.C. Dulles Intl

Tue 8/25

4:15 pm-8:53 pm

1 stop7h 38m

$449

OntarioWashington, D.C.

ONT - DCA

ONTDCA

Ontario

Tue 8/4

8:30 am-8:55 pm

2 stops9h 25m

Washington, D.C. Reagan-National

Wed 8/19

6:40 pm-7:25 am

2 stops15h 45m

$453

OntarioBaltimore

ONT - BWI

ONTBWI

Ontario

Thu 8/13

7:13 pm-11:45 am

2 stops13h 32m

Baltimore/Washington

Thu 8/20

3:04 pm-9:59 pm

1 stop9h 55m

$454

OntarioWashington, D.C.

ONT - DCA

ONTDCA

Ontario

Wed 9/23

7:00 am-6:09 pm

1 stop8h 09m

Washington, D.C. Reagan-National

Mon 9/28

12:57 pm-10:59 pm

2 stops13h 02m

$454

OntarioWashington, D.C.

ONT - IAD

ONTIAD

Ontario

Fri 9/25

1:52 pm-1:13 am

1 stop8h 21m

Washington, D.C. Dulles Intl

Mon 9/28

3:02 pm-9:59 pm

1 stop9h 57m

$465

Flights are sorted by cheapest round-trip flights first.

Deals found on 6/28

Showing 1-10 of 60 resultsSorted by cheapest first
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Compare providers for flights from Ontario to Washington, D.C.

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 Washington, D.C. in June.
ProviderPrice AccuracyTrust Score*
ExpediaPrice Accuracy1 starTrust Score*3 stars
FlightHubPrice Accuracy3 starsTrust Score*3 stars
MytripPrice Accuracy2 starsTrust Score*3 stars
JustAirTicketPrice 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 Ontario-Washington, D.C. 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. flight deals on Cheapflights vs. FlightHub >95% of the time. Price accuracy is based on data collected from Ontario-Washington, D.C. flight searches over the past month and is updated monthly.
  • Most trusted provider: When it comes to deals on Ontario-Washington, D.C. 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. 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 Washington, D.C.

Have a flexible travel schedule? Discover the best time to fly to Washington, D.C. 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.

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

Currently, July is the cheapest month in which you can book a flight from Ontario to Washington, D.C. (average of $68). Flying from Ontario to Washington, D.C. in February is currently the most expensive (average of $221). 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 WAS?

Find hourly flight availability from Ontario to Washington, D.C.. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated June 29, 2026.

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

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

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

The price you pay for your flight from Ontario to Washington, D.C. 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.

Reviews of airlines servicing Washington, D.C.

Get insights into the airlines that provide service to Washington, D.C.. 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 Washington, D.C.. Reviews last updated June 29, 2026.
Read through reviews of airlines operating flights from Ontario to Washington, D.C., such as Southwest,Delta, andUnited Airlines. Reviews also offer insight into each airline's entertainment options, comfort, food, crew/service, and boarding process.
Southwest
7.9
Good
4,246 reviews

Boarding

8.1

Entertainment

7.5

Crew

8.6

Food

7.0

Overall

7.9

Comfort

8.0

Reviews

1 / 20
8.0
Excellent

La Tracimeldamarcos,Jun 2026

LAX - SLC

The second flight was not as comfortable as the first as we had to change planes to what seemed to be a slightly older aircraft. The seats weren’t as comfortable as the other plane. But it wasn’t bad.
Southwest
7.9
Good
4,246 reviews
Southwest
7.9
Good
4,246 reviews

Boarding

8.1

Entertainment

7.5

Crew

8.6

Food

7.0

Overall

7.9

Comfort

8.0

Reviews

1 / 20
8.0
Excellent

La Tracimeldamarcos,Jun 2026

LAX - SLC

The second flight was not as comfortable as the first as we had to change planes to what seemed to be a slightly older aircraft. The seats weren’t as comfortable as the other plane. But it wasn’t bad.
Delta
7.8
Good
8,449 reviews
Southwest
7.9
Good
4,246 reviews

Boarding

8.1

Entertainment

7.5

Crew

8.6

Food

7.0

Overall

7.9

Comfort

8.0

Reviews

1 / 20
8.0
Excellent

La Tracimeldamarcos,Jun 2026

LAX - SLC

The second flight was not as comfortable as the first as we had to change planes to what seemed to be a slightly older aircraft. The seats weren’t as comfortable as the other plane. But it wasn’t bad.
United Airlines
7.4
Good
9,894 reviews
Southwest
7.9
Good
4,246 reviews

Boarding

8.1

Entertainment

7.5

Crew

8.6

Food

7.0

Overall

7.9

Comfort

8.0

Reviews

1 / 20
8.0
Excellent

La Tracimeldamarcos,Jun 2026

LAX - SLC

The second flight was not as comfortable as the first as we had to change planes to what seemed to be a slightly older aircraft. The seats weren’t as comfortable as the other plane. But it wasn’t bad.
American Airlines
7.1
Good
11,768 reviews
Southwest
7.9
Good
4,246 reviews

Boarding

8.1

Entertainment

7.5

Crew

8.6

Food

7.0

Overall

7.9

Comfort

8.0

Reviews

1 / 20
8.0
Excellent

La Tracimeldamarcos,Jun 2026

LAX - SLC

The second flight was not as comfortable as the first as we had to change planes to what seemed to be a slightly older aircraft. The seats weren’t as comfortable as the other plane. But it wasn’t bad.
Frontier
5.6
Fair
2,854 reviews
Southwest
7.9
Good
4,246 reviews

Boarding

8.1

Entertainment

7.5

Crew

8.6

Food

7.0

Overall

7.9

Comfort

8.0

Reviews

1 / 20
8.0
Excellent

La Tracimeldamarcos,Jun 2026

LAX - SLC

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

Related info for your journey

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

    If you book a flight to Washington, D.C. from Ontario, you will be flying from Ontario, which is the city’s only airport. Ontario (ONT) is located 3.1 mi from the center of Ontario. There are 0 flights from Ontario to Washington, D.C. per day from 5 different airlines.

  • How long is the flight from Ontario to Washington, D.C.?

    Departing from Ontario to Washington, D.C. will take you 7h 08m. Ontario and Washington, D.C. are separated by a distance of 2258 mi. This flight may include one or multiple stops.

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

    Cheapflights users have booked flights from Ontario to Washington, D.C. round-trip from $166. Other airlines that can offer you cheap pricing are Delta, from $172, and United Airlines, from $226. Users have found that Frontier is 57% cheaper than the other options available to this destination.

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

    For one-way options, check prices for Frontier. According to our data, you can fly for as low as $77. Users have also found prices from $128 and $129 on United Airlines and Southwest, respectively.

  • What are the most popular routes from Ontario to Washington, D.C.?

    When deciding which route to take from Ontario to Washington, D.C. consider Ontario - Washington, D.C. Dulles Intl, Ontario - Baltimore/Washington or Ontario - Washington, D.C. Reagan-National as they are the most popular.

  • Can I find deals for flights from Ontario to Washington, D.C. that include hotel bookings?

    Yes. In addition to deals on Ontario to Washington, D.C. flights, Cheapflights offers vacation packages that include both flights and hotel.

  • How can I find direct flights from Ontario to Washington, D.C.?

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

  • Can I find deals for business class flights from Ontario to Washington, D.C.?

    Yes. Cheapflights offers flight deals from Ontario to Washington, D.C. 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.?

    Currently, July is the cheapest month in which you can book a flight from Ontario to Washington, D.C. (average of $68). Flying from Ontario to Washington, D.C. in February is currently the most expensive (average of $221). 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 Washington, D.C.?

Book flights to Washington, D.C. if you plan to visit one of these locations
Alexandria
Arlington
Tysons
Owings Mills
Springfield
Lanham
Reston
Herndon
Rockville
Hyattsville
Falls Church
Fredericksburg
Hanover
Manassas
Silver Spring
Laurel
Clinton
Hunt Valley
Cordova
Woodbridge

Browse thousands of different options on Cheapflights for your next trip

Toggle through the tabs below to find thousands of options on Cheapflights for your next trip.

Top 5 airlines flying from Ontario to Washington, D.C.

Discover the top 5 airlines that operate flights from Ontario to Washington, D.C.. 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 June 29, 2026.
AirlineCheapestAverageFlexibilityOn-time
FrontierCheapest$166Average$291FlexibilityNo cancel feeOn-time62%
DeltaCheapest$172Average$431FlexibilityNo cancel feeOn-timeN/A
United AirlinesCheapest$226Average$469FlexibilityNo cancel feeOn-time69%
American AirlinesCheapest$256Average$544FlexibilityNo cancel feeOn-time71%
SouthwestCheapest$258Average$466FlexibilityNo cancel feeOn-time63%

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