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Washington, D.C.

$65+ 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 4/14. Fares are subject to change and may not be available on all flights or dates of travel.
ONT — WAS
Apr 27 — May 41
Mon 4/27
Mon 5/4
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

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

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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 March 28, 2026.

This Trip.com deal was found by Cheapflights users on 3/26. 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 Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 4/1412:59 am
ONT
-
DCA
1 stop13h 00m
Frontier
Sat 4/186:00 pm
DCA
-
ONT
1 stop8h 55m
Frontier
Deal found 3/26$148
This Trip.com deal was found by Cheapflights users on 3/24. 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 Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 4/1312:59 am
ONT
-
DCA
1 stop9h 01m
Frontier
Thu 4/168:00 am
DCA
-
ONT
1 stop26h 31m
Frontier
Deal found 3/24$155
This CheapOair deal was found by Cheapflights users on 3/27. 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.
Fri 5/18:26 am
ONT
-
BWI
1 stop8h 43m
Frontier
Tue 5/54:29 pm
BWI
-
ONT
1 stop18h 06m
Frontier
Deal found 3/27$160
This Frontier deal was found by Cheapflights users on 3/27. 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 5/112:59 am
ONT
-
DCA
1 stop9h 01m
Frontier
Sat 5/91:59 pm
DCA
-
ONT
1 stop12h 50m
Frontier
Deal found 3/27$160
This Booking.com deal was found by Cheapflights users on 3/27. 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 4/1512:59 am
ONT
-
DCA
1 stop9h 00m
Frontier
Sat 4/256:00 pm
DCA
-
ONT
1 stop8h 55m
Frontier
Deal found 3/27$161
This Booking.com deal was found by Cheapflights users on 3/27. 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 5/68:06 pm
ONT
-
BWI
1 stop21h 17m
Frontier
Wed 5/135:17 pm
BWI
-
ONT
1 stop17h 18m
Frontier
Deal found 3/27$162
This Orbitz deal was found by Cheapflights users on 3/25. 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 Orbitz is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 5/18:26 am
ONT
-
BWI
1 stop8h 43m
Frontier
Mon 5/412:15 pm
BWI
-
ONT
1 stop22h 20m
Frontier
Deal found 3/25$166
This Booking.com deal was found by Cheapflights users on 3/25. 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.
Wed 4/2212:59 am
ONT
-
DCA
1 stop9h 00m
Frontier
Sun 4/266:00 pm
DCA
-
ONT
1 stop16h 31m
Frontier
Deal found 3/25$167
This Kiwi.com deal was found by Cheapflights users on 3/26. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 4/1412:59 am
ONT
-
DCA
1 stop13h 00m
Frontier
Tue 4/217:59 am
DCA
-
ONT
1 stop18h 56m
Frontier
Deal found 3/26$170
This CheapOair deal was found by Cheapflights users on 3/27. 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.
Fri 4/175:33 pm
ONT
-
DCA
1 stop16h 26m
Frontier
Sat 4/256:00 pm
DCA
-
ONT
1 stop8h 55m
Frontier
Deal found 3/27$171
This Booking.com deal was found by Cheapflights users on 3/25. 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.
Thu 5/78:06 pm
ONT
-
BWI
1 stop21h 17m
Frontier
Sat 5/95:34 pm
BWI
-
ONT
1 stop17h 01m
Frontier
Deal found 3/25$172
This Booking.com deal was found by Cheapflights users on 3/26. 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 Booking.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 4/3012:59 am
ONT
-
DCA
1 stop18h 00m
Frontier
Mon 5/46:00 pm
DCA
-
ONT
1 stop19h 05m
Frontier
Deal found 3/26$172

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 March 28, 2026.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$148
(Trip.com)

One-way from

$65
(Trip.com)

Popular in

December

Cheapest in

January

Average price

$373

Good round-trip deal

$377 or less

Good one-way deal

$189 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. 17% potential increase in price ($76 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 6% potential price decrease ($23 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in March 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 March 28, 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 4/28

12:49 pm-12:38 am

1 stop8h 49m

Baltimore/Washington

Tue 5/5

6:00 am-11:36 am

1 stop8h 36m

$311

OntarioWashington, D.C.

ONT - IAD

ONTIAD

Ontario

Tue 5/5

10:39 am-12:09 am

1 stop10h 30m

Washington, D.C. Dulles Intl

Tue 5/12

7:10 am-2:32 pm

1 stop10h 22m

$322

OntarioBaltimore

ONT - BWI

ONTBWI

Ontario

Thu 4/23

5:05 pm-6:00 am

1 stop9h 55m

Baltimore/Washington

Tue 4/28

6:00 am-11:36 am

1 stop8h 36m

$344

OntarioWashington, D.C.

ONT - IAD

ONTIAD

Ontario

Tue 4/28

11:53 am-11:55 pm

1 stop9h 02m

Washington, D.C. Dulles Intl

Mon 5/4

7:00 am-1:39 pm

1 stop9h 39m

$344

OntarioWashington, D.C.

ONT - DCA

ONTDCA

Ontario

Sat 4/25

6:00 am-8:33 pm

2 stops11h 33m

Washington, D.C. Reagan-National

Tue 4/28

2:34 pm-11:44 pm

2 stops12h 10m

$354

OntarioBaltimore

ONT - BWI

ONTBWI

Ontario

Wed 4/22

3:26 pm-5:44 am

1 stop11h 18m

Baltimore/Washington

Sat 4/25

7:04 am-2:32 pm

1 stop10h 28m

$397

OntarioWashington, D.C.

ONT - IAD

ONTIAD

Ontario

Tue 4/21

6:00 am-6:11 pm

1 stop9h 11m

Washington, D.C. Dulles Intl

Tue 4/28

7:10 am-2:32 pm

1 stop10h 22m

$400

OntarioWashington, D.C.

ONT - DCA

ONTDCA

Ontario

Thu 4/16

12:49 pm-11:41 pm

1 stop7h 52m

Washington, D.C. Reagan-National

Mon 4/20

9:40 am-9:00 pm

2 stops14h 20m

$404

OntarioBaltimore

ONT - BWI

ONTBWI

Ontario

Thu 5/28

11:55 am-11:55 pm

2 stops9h 00m

Baltimore/Washington

Thu 6/4

6:05 am-11:20 am

2 stops8h 15m

$411

OntarioWashington, D.C.

ONT - DCA

ONTDCA

Ontario

Tue 5/5

10:15 pm-9:09 am

1 stop7h 54m

Washington, D.C. Reagan-National

Sat 7/4

12:17 pm-6:25 pm

1 stop9h 08m

$417

Flights are sorted by cheapest round-trip flights first.

Deals found on 3/26

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 March.
ProviderPrice AccuracyTrust Score*
ExpediaPrice Accuracy1 starTrust Score*3 stars
FlightHubPrice Accuracy3 starsTrust 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. 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, August is the cheapest month in which you can book a flight from Ontario to Washington, D.C. (average of $93). Flying from Ontario to Washington, D.C. in March is currently the most expensive (average of $195). 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 March 28, 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.?

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

Share of 1-stop round-trip flights from Ontario to Washington, D.C. chosen by Cheapflights users in the past 12 months, using the same layover each way.

Denver (DEN) – chosen by Cheapflights users on 80% of 1-stop itineraries from Ontario to Washington, D.C. on Cheapflights.

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

Average round-trip fare for 1-stop flights from Ontario to Washington, D.C., chosen by Cheapflights users in the past 12 months, with the same layover each way.

Denver (DEN) is the most affordable 1-stop option, with an average round-trip price of $380.

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

Shortest average travel time for 1-stop one-way flights from Ontario to Washington, D.C., based on itineraries clicked by Cheapflights users over the past 12 months, grouped by layover airport.

Flights via Denver (DEN) have the shortest average one-way travel time for 1-stop routes: 8h 01m.

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

Average layover duration for 1-stop one-way flights from Ontario to Washington, D.C., chosen by Cheapflights users in the last 12 months, grouped by stopover airport.

Flights via Denver (DEN) offer the fastest connection on this route, with an average layover time of 2h 23m.

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 March 28, 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
8.0
Very good
4,333 reviews

Comfort

8.0

Overall

8.0

Boarding

8.1

Entertainment

7.5

Food

7.0

Crew

8.6

Reviews

1 / 20
10.0
Excellent

William Drew,Nov 2025

SJC - HNL

Flight crew was amazing! Usually they're very good on Southwest, but this crew went above and beyond. I have never ever seen so many rounds of drink service on a flight before.
Southwest
8.0
Very good
4,333 reviews
Southwest
8.0
Very good
4,333 reviews

Comfort

8.0

Overall

8.0

Boarding

8.1

Entertainment

7.5

Food

7.0

Crew

8.6

Reviews

1 / 20
10.0
Excellent

William Drew,Nov 2025

SJC - HNL

Flight crew was amazing! Usually they're very good on Southwest, but this crew went above and beyond. I have never ever seen so many rounds of drink service on a flight before.
Delta
7.9
Good
8,356 reviews
Southwest
8.0
Very good
4,333 reviews

Comfort

8.0

Overall

8.0

Boarding

8.1

Entertainment

7.5

Food

7.0

Crew

8.6

Reviews

1 / 20
10.0
Excellent

William Drew,Nov 2025

SJC - HNL

Flight crew was amazing! Usually they're very good on Southwest, but this crew went above and beyond. I have never ever seen so many rounds of drink service on a flight before.
United Airlines
7.4
Good
9,499 reviews
Southwest
8.0
Very good
4,333 reviews

Comfort

8.0

Overall

8.0

Boarding

8.1

Entertainment

7.5

Food

7.0

Crew

8.6

Reviews

1 / 20
10.0
Excellent

William Drew,Nov 2025

SJC - HNL

Flight crew was amazing! Usually they're very good on Southwest, but this crew went above and beyond. I have never ever seen so many rounds of drink service on a flight before.
American Airlines
7.1
Good
11,520 reviews
Southwest
8.0
Very good
4,333 reviews

Comfort

8.0

Overall

8.0

Boarding

8.1

Entertainment

7.5

Food

7.0

Crew

8.6

Reviews

1 / 20
10.0
Excellent

William Drew,Nov 2025

SJC - HNL

Flight crew was amazing! Usually they're very good on Southwest, but this crew went above and beyond. I have never ever seen so many rounds of drink service on a flight before.
Frontier
5.7
Fair
3,013 reviews
Southwest
8.0
Very good
4,333 reviews

Comfort

8.0

Overall

8.0

Boarding

8.1

Entertainment

7.5

Food

7.0

Crew

8.6

Reviews

1 / 20
10.0
Excellent

William Drew,Nov 2025

SJC - HNL

Flight crew was amazing! Usually they're very good on Southwest, but this crew went above and beyond. I have never ever seen so many rounds of drink service on a flight before.

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 6 different airlines.

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

    Departing from Ontario to Washington, D.C. will take you 8h 49m. Ontario and Washington, D.C. are separated by a distance of 2276 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 54% 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 $71. Users have also found prices from $129 and $138 on Southwest and American Airlines, 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. Reagan-National, Ontario - Washington, D.C. Dulles Intl or Ontario - Baltimore/Washington 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, August is the cheapest month in which you can book a flight from Ontario to Washington, D.C. (average of $93). Flying from Ontario to Washington, D.C. in March is currently the most expensive (average of $195). 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
Woodbridge
Tysons
Owings Mills
Arlington
Springfield
Silver Spring
Herndon
Hyattsville
Hanover
Laurel
Rockville
Upper Marlboro
Fredericksburg
Largo
Bowie
Clinton
Towson
College Park
Cordova

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 6 airlines flying from Ontario to Washington, D.C.

Discover the top 6 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 March 28, 2026.
AirlineCheapestAverageFlexibilityOn-time
Spirit AirlinesCheapest$72Average$234FlexibilityNo cancel feeOn-time65%
FrontierCheapest$136Average$272FlexibilityNo cancel feeOn-time62%
DeltaCheapest$172Average$403FlexibilityNo cancel feeOn-timeN/A
United AirlinesCheapest$226Average$440FlexibilityNo cancel feeOn-time69%
American AirlinesCheapest$256Average$475FlexibilityNo cancel feeOn-time71%
SouthwestCheapest$258Average$458FlexibilityNo cancel feeOn-time63%

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