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Washington, D.C.

$92+ 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 1/24. Fares are subject to change and may not be available on all flights or dates of travel.
ONT — WAS
oct. 15 — oct. 221
mié. 10/15
mié. 10/22
1 adult, Economy
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Cheapflights Tip: The best prices from Ontario to Washington, D.C. are usually found in May or August, booked 25 days in advance, depart on a Wednesday or Thursday and return on a Tuesday

Cheap 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 septiembre 15, 2025.

Round-trip from

$176
(Frontier)

One-way from

$92
(American Airlines)

Popular in

November

Cheapest in

May

Average price

$314

Good round-trip deal

$383 or less

Good one-way deal

$167 or less
From Ontario to Washington, D.C. (WAS)
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One-way flight from Ontario to Washington, D.C. (WAS)
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Highest demand for flights based on searches. 15% potential increase in price ($63 potential increase over avg. RT price).
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Cheapest flight prices on average. 2% potential price decrease ($9 potential savings vs. average RT price).
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Average for round-trip flights in September 2025
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Price to beat on a round-trip flight from Ontario to Washington, D.C. (WAS).
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Price to beat on a one-way flight from Ontario to Washington, D.C. (WAS).
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Find 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 septiembre 15, 2025.

This Frontier deal was found by Cheapflights users on 9/15. 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.
vie. 11/148:24 amONT - BWI
1 stop7h 16mFrontier
dom. 11/169:59 pmBWI - ONT
1 stop11h 58mFrontier
Deal found 9/15$176
This United Airlines deal was found by Cheapflights users on 9/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
sáb. 10/185:05 amONT - BWI
1 stop7h 08mUnited Airlines
sáb. 10/254:21 pmBWI - ONT
1 stop7h 03mUnited Airlines
Deal found 9/15$185
This American Airlines deal was found by Cheapflights users on 9/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
sáb. 10/2510:09 amONT - BWI
2 stops11h 24mAmerican Airlines
mar. 10/289:30 amBWI - ONT
2 stops12h 05mAmerican Airlines
Deal found 9/14$195
This Booking.com deal was found by Cheapflights users on 9/14. 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.
jue. 10/2310:30 amONT - BWI
1 stop28h 14mFrontier
dom. 11/29:59 pmBWI - ONT
1 stop12h 30mFrontier
Deal found 9/14$205
This Booking.com deal was found by Cheapflights users on 9/14. 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.
dom. 10/58:59 pmONT - BWI
1 stop17h 43mFrontier
dom. 10/129:42 pmBWI - ONT
1 stop13h 07mFrontier
Deal found 9/14$209
This Booking.com deal was found by Cheapflights users on 9/15. 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.
jue. 10/23:43 pmONT - BWI
1 stop22h 59mFrontier
dom. 10/56:27 pmBWI - ONT
1 stop16h 26mFrontier
Deal found 9/15$217
This Booking.com deal was found by Cheapflights users on 9/15. 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.
mié. 9/248:59 pmONT - DCA
1 stop12h 11mFrontier
sáb. 9/271:00 pmDCA - ONT
1 stop9h 54mFrontier
Deal found 9/15$225
This Booking.com deal was found by Cheapflights users on 9/14. 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.
jue. 9/258:59 pmONT - BWI
1 stop17h 43mFrontier
vie. 10/36:27 pmBWI - ONT
1 stop28h 27mFrontier
Deal found 9/14$226
This Frontier deal was found by Cheapflights users on 9/14. 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.
jue. 11/137:22 amONT - BWI
2 stops13h 45mFrontier
lun. 11/174:30 pmBWI - ONT
2 stops10h 20mFrontier
Deal found 9/14$228
This Booking.com deal was found by Cheapflights users on 9/15. 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.
mié. 9/248:59 pmONT - DCA
1 stop22h 00mFrontier
vie. 9/266:00 pmDCA - ONT
1 stop28h 54mFrontier
Deal found 9/15$230
This Booking.com deal was found by Cheapflights users on 9/14. 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.
jue. 9/258:59 pmONT - DCA
1 stop12h 11mFrontier
lun. 9/296:00 pmDCA - ONT
1 stop28h 54mFrontier
Deal found 9/14$231
This Cheapflightsfares deal was found by Cheapflights users on 9/14. 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 Cheapflightsfares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
vie. 10/246:53 amONT - DCA
1 stop7h 06mFrontier
mar. 10/286:31 pmDCA - ONT
1 stop8h 19mFrontier
Deal found 9/14$232

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 septiembre 15, 2025.
Use the filters below to find and compare flights from Ontario to Washington, D.C. that are best for you.

Fly from

Ontario

Fly to

Washington, D.C.

Route

Depart

Return

Price

OntarioWashington, D.C.

ONT - DCA

ONTDCA

Ontario

vie. 10/3

8:59 pm-9:59 pm

1 stop22h 00m

Washington, D.C. Reagan-National

lun. 10/6

7:00 am-8:56 pm

2 stops16h 56m

$239

OntarioBaltimore

ONT - BWI

ONTBWI

Ontario

mar. 11/18

6:00 am-7:21 pm

2 stops10h 21m

Baltimore/Washington

lun. 11/24

5:12 pm-10:31 pm

1 stop8h 19m

$250

OntarioWashington, D.C.

ONT - DCA

ONTDCA

Ontario

jue. 9/18

8:59 pm-9:59 pm

1 stop22h 00m

Washington, D.C. Reagan-National

mar. 9/23

7:00 am-7:54 pm

1 stop15h 54m

$266

OntarioBaltimore

ONT - BWI

ONTBWI

Ontario

vie. 10/10

6:53 am-5:32 pm

1 stop7h 39m

Baltimore/Washington

vie. 10/17

6:17 pm-11:50 pm

1 stop8h 33m

$273

OntarioBaltimore

ONT - BWI

ONTBWI

Ontario

lun. 12/8

10:25 pm-11:12 am

1 stop9h 47m

Baltimore/Washington

jue. 12/11

7:15 am-12:22 pm

1 stop8h 07m

$277

OntarioBaltimore

ONT - BWI

ONTBWI

Ontario

sáb. 11/8

11:36 am-10:09 pm

1 stop7h 33m

Baltimore/Washington

sáb. 11/15

6:00 am-10:40 am

1 stop7h 40m

$277

OntarioWashington, D.C.

ONT - DCA

ONTDCA

Ontario

sáb. 11/8

11:36 am-9:43 pm

1 stop7h 07m

Washington, D.C. Reagan-National

sáb. 11/15

6:00 am-10:40 am

1 stop7h 40m

$277

OntarioWashington, D.C.

ONT - IAD

ONTIAD

Ontario

mié. 11/12

11:46 am-12:54 am

1 stop10h 08m

Washington, D.C. Dulles Intl

mié. 11/19

6:00 am-10:40 am

1 stop7h 40m

$277

OntarioWashington, D.C.

ONT - IAD

ONTIAD

Ontario

vie. 2/20

10:30 pm-9:11 am

1 stop7h 41m

Washington, D.C. Dulles Intl

mar. 2/24

7:15 am-12:34 pm

1 stop8h 19m

$277

OntarioWashington, D.C.

ONT - IAD

ONTIAD

Ontario

mar. 10/14

11:48 am-12:40 am

1 stop9h 52m

Washington, D.C. Dulles Intl

mié. 10/15

7:35 am-5:10 pm

1 stop12h 35m

$277

Flights are sorted by cheapest round-trip flights first.

Deals found on 9/15

Showing 1-10 of 60 results
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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.

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

Use this chart to determine the optimal time to book a round-trip flight from Ontario to Washington, D.C.. Price data was last updated on September 12, 2025.

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 25 days in advance of your trip. Fares are likely to increase a fortnight or so before your departure date.

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

Currently, August is the cheapest month in which you can book a flight from Ontario to Washington, D.C. (average of $292). Flying from Ontario to Washington, D.C. in April is currently the most expensive (average of $337). 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 septiembre 15, 2025.

It’s typically best to fly out from Ontario to Washington, D.C. in the afternoon. Doing so could potentially save you 32% on the flight price compared to flying at noon, which is usually more expensive.

What is the cheapest day to fly from Ontario to Washington, D.C.?

Use this chart to determine the cheapest time to fly round-trip from Ontario to Washington, D.C.. Price data was last updated on September 14, 2025.

Travelers seeking maximum savings on their Ontario to Washington, D.C. flight should consider departing on Wednesday evenings when fares are most often at their lowest. Monday mornings flights should be avoided if possible as fares are typically the most expensive at this time.

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 96% 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 $280.

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: 7h 16m.

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 1h 26m.

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 septiembre 15, 2025.
Read through reviews of airlines operating flights from Ontario to Washington, D.C., such as Southwest, Delta, and United Airlines. Reviews also offer insight into each airline's entertainment options, comfort, food, crew/service, and boarding process.
Southwest
8.0
Very good
4,242 reviews

Food

7.0

Boarding

8.1

Comfort

8.0

Crew

8.6

Overall

8.0

Entertainment

7.5

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
4,242 reviews
Southwest
8.0
Very good
4,242 reviews

Food

7.0

Boarding

8.1

Comfort

8.0

Crew

8.6

Overall

8.0

Entertainment

7.5

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.
Delta
8.0
Very good
7,954 reviews
Southwest
8.0
Very good
4,242 reviews

Food

7.0

Boarding

8.1

Comfort

8.0

Crew

8.6

Overall

8.0

Entertainment

7.5

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.
United Airlines
7.4
Good
8,929 reviews
Southwest
8.0
Very good
4,242 reviews

Food

7.0

Boarding

8.1

Comfort

8.0

Crew

8.6

Overall

8.0

Entertainment

7.5

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.
American Airlines
7.2
Good
10,000 reviews
Southwest
8.0
Very good
4,242 reviews

Food

7.0

Boarding

8.1

Comfort

8.0

Crew

8.6

Overall

8.0

Entertainment

7.5

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.
Frontier
5.8
Fair
3,172 reviews
Southwest
8.0
Very good
4,242 reviews

Food

7.0

Boarding

8.1

Comfort

8.0

Crew

8.6

Overall

8.0

Entertainment

7.5

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.

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 9h 47m. 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 $147. Other airlines that can offer you cheap pricing are United Airlines, from $226, and Southwest, from $258. 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 United Airlines. According to our data, you can fly for as low as $93. Users have also found prices from $130 and $138 on American Airlines and Hawaiian 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. Dulles Intl, Ontario - Washington, D.C. Reagan-National 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 $292). Flying from Ontario to Washington, D.C. in April is currently the most expensive (average of $337). 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
Woodbridge
Alexandria
Arlington
Tysons
Silver Spring
Springfield
Gaithersburg
Fredericksburg
Linthicum Heights
Fairfax
Falls Church
Owings Mills
Manassas
Rockville
Hanover
Oxon Hill
Laurel
Towson
Dundalk
National Harbor

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Alternative routes for Ontario to Washington, D.C.

See prices for flight routes from nearby airports that may be better suited for you.
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Top 6 airlines flying from Ontario to 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 septiembre 15, 2025.
AirlineCheapestAverageFlexibilityOn-time
Spirit AirlinesCheapest$98Average$224FlexibilityNo cancel feeOn-time65%
FrontierCheapest$147Average$270FlexibilityNo cancel feeOn-time62%
United AirlinesCheapest$226Average$464FlexibilityNo cancel feeOn-time69%
SouthwestCheapest$258Average$469FlexibilityNo cancel feeOn-time63%
American AirlinesCheapest$278Average$478FlexibilityNo cancel feeOn-time71%
DeltaCheapest$284Average$425FlexibilityNo cancel feeOn-timeN/A

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