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Ontario

$102+ Cheap flights from Washington, D.C. (WAS) 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 4/16. Fares are subject to change and may not be available on all flights or dates of travel.
WAS — ONT
Mar 30 — Apr 61
Sun 3/30
Sun 4/6
1 adult, Economy
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Cheapflights Tip: The best prices from Washington, D.C. to Ontario are usually found in August or October, booked 78 days in advance, depart on a Tuesday or Saturday and return on a Wednesday

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

Discover tips and strategies to find the most affordable flight options for your journey from Washington, D.C. (WAS) to Ontario (ONT). 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 25, 2025.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$276
(Delta)

One-way from

$102
(American Airlines)

Popular in

June

Cheapest in

August

Average price

$426

Good round-trip deal

$488 or less
Provider with most accurate pricing for Washington, D.C. (WAS)-Ontario flight deals.
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Provider most trusted by Cheapflights users for Washington, D.C. (WAS)-Ontario flights.
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From Washington, D.C. (WAS) to Ontario
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One-way flight from Washington, D.C. (WAS) to Ontario
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Highest demand for flights based on searches. 2% potential increase in price ($10 potential increase over avg. RT price).
Search Deals
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 March 2025
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Price to beat on a round-trip flight from Washington, D.C. (WAS) to Ontario.
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Find flight deals from Washington, D.C. to Ontario

Cheapest flights from Washington, D.C. to Ontario
Explore the most affordable flight options available from Washington, D.C. to Ontario. Find the lowest fares from popular airlines and budget airlines, with prices last updated on March 25, 2025.

This Delta 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 4/266:30 amBWI - ONT
1 stop7h 27mDelta
Sat 5/312:07 pmONT - BWI
1 stop6h 49mDelta
Deal found 3/24$276
This Frontier 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 4/312:05 pmBWI - ONT
1 stop8h 08mFrontier
Sun 4/612:59 amONT - BWI
1 stop7h 28mFrontier
Deal found 3/24$278
This Frontier 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 4/17:00 amDCA - ONT
1 stop10h 27mFrontier
Tue 5/612:59 amONT - DCA
1 stop8h 08mFrontier
Deal found 3/24$278
This CheapOair 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 5/128:01 amIAD - ONT
1 stop8h 15mFrontier
Fri 5/1610:17 pmONT - IAD
1 stop29h 14mFrontier
Deal found 3/24$280
This United Airlines deal was found by Cheapflights users on 3/23. 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.
Sat 5/246:37 amBWI - ONT
1 stop8h 37mUnited Airlines
Tue 5/276:32 pmONT - BWI
1 stop7h 48mUnited Airlines
Deal found 3/23$306
This Alaska Airlines 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 Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 5/37:06 amBWI - ONT
1 stop11h 26mAlaska Airlines
Wed 5/74:29 pmONT - BWI
1 stop10h 17mAlaska Airlines
Deal found 3/24$311
This American Airlines 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 5/63:29 pmBWI - ONT
1 stop9h 29mAmerican Airlines
Wed 5/1412:41 pmONT - BWI
1 stop7h 40mAmerican Airlines
Deal found 3/24$312
This American Airlines 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 5/175:02 amIAD - ONT
2 stops11h 50mAmerican Airlines
Sat 5/2412:41 pmONT - IAD
1 stop7h 16mAmerican Airlines
Deal found 3/25$322
This Travelocity 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 Travelocity is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 5/16:30 amIAD - ONT
1 stop12h 02mMultiple Airlines
Mon 5/52:28 pmONT - IAD
1 stop13h 03mMultiple Airlines
Deal found 3/24$323
This Delta 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 4/266:00 amDCA - ONT
1 stop7h 57mDelta
Sat 5/312:07 pmONT - DCA
1 stop7h 31mDelta
Deal found 3/24$326
This Alaska Airlines 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 Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/306:30 amIAD - ONT
1 stop12h 02mAlaska Airlines
Mon 5/56:24 pmONT - IAD
1 stop10h 19mAlaska Airlines
Deal found 3/25$326
This Delta 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/97:35 amIAD - ONT
1 stop7h 51mDelta
Wed 4/161:20 pmONT - IAD
1 stop7h 11mDelta
Deal found 3/24$327

Cheapflights Fare Finder

Customize your flight search to find flights from Washington, D.C. to Ontario 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 25, 2025.
Use the filters below to find and compare flights from Washington, D.C. to Ontario that are best for you.

Fly from

Washington, D.C.

Fly to

Ontario

Route

Depart

Return

Price

BaltimoreOntario

BWI - ONT

BWIONT

Baltimore/Washington

Sat 4/26

6:30 am-10:57 am

1 stop7h 27m

Ontario

Sat 5/3

12:07 pm-9:56 pm

1 stop6h 49m

$276

BaltimoreOntario

BWI - ONT

BWIONT

Baltimore/Washington

Fri 4/4

8:50 pm-7:39 am

1 stop13h 49m

Ontario

Sun 5/11

12:59 am-5:22 pm

1 stop13h 23m

$278

Washington, D.C.Ontario

IAD - ONT

IADONT

Washington, D.C. Dulles Intl

Mon 5/12

8:01 am-1:16 pm

1 stop8h 15m

Ontario

Fri 5/16

10:17 pm-6:31 am

1 stop29h 14m

$280

Washington, D.C.Ontario

DCA - ONT

DCAONT

Washington, D.C. Reagan-National

Sat 4/5

1:03 pm-5:57 pm

1 stop7h 54m

Ontario

Tue 4/8

3:17 pm-12:04 pm

1 stop17h 47m

$290

BaltimoreOntario

BWI - ONT

BWIONT

Baltimore/Washington

Sat 5/24

6:37 am-12:14 pm

1 stop8h 37m

Ontario

Tue 5/27

6:32 pm-5:20 am

1 stop7h 48m

$306

BaltimoreOntario

BWI - ONT

BWIONT

Baltimore/Washington

Sat 5/3

7:06 am-3:32 pm

1 stop11h 26m

Ontario

Wed 5/7

4:29 pm-5:46 am

1 stop10h 17m

$311

BaltimoreOntario

BWI - ONT

BWIONT

Baltimore/Washington

Tue 5/6

3:29 pm-9:58 pm

1 stop9h 29m

Ontario

Wed 5/14

12:41 pm-11:21 pm

1 stop7h 40m

$312

Washington, D.C.Ontario

IAD - ONT

IADONT

Washington, D.C. Dulles Intl

Sat 5/17

5:02 am-1:52 pm

2 stops11h 50m

Ontario

Sat 5/24

12:41 pm-10:57 pm

1 stop7h 16m

$322

Washington, D.C.Ontario

IAD - ONT

IADONT

Washington, D.C. Dulles Intl

Thu 5/1

6:30 am-3:32 pm

1 stop12h 02m

Ontario

Mon 5/5

2:28 pm-6:31 am

1 stop13h 03m

$323

Washington, D.C.Ontario

DCA - ONT

DCAONT

Washington, D.C. Reagan-National

Sat 4/26

6:00 am-10:57 am

1 stop7h 57m

Ontario

Sat 5/3

12:07 pm-10:38 pm

1 stop7h 31m

$326

Flights are sorted by cheapest round-trip flights first.

Deals found on 3/23

Showing 1-10 of 45 results
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Compare providers for flights from Washington, D.C. 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 Washington, D.C. to Ontario in March.
ProviderPrice AccuracyTrust Score*
ExpediaPrice Accuracy1 starTrust Score*3 stars
FlightHubPrice Accuracy3 starsTrust Score*3 stars
eDreamsPrice Accuracy3 starsTrust Score*3 stars
MytripPrice Accuracy3 starsTrust Score*3 stars
Kiwi.comPrice Accuracy3 starsTrust Score*2 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.-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.-Ontario flight deals on Cheapflights vs. FlightHub >95% of the time. Price accuracy is based on data collected from Washington, D.C.-Ontario flight searches over the past month and is updated monthly.
  • Most trusted provider: When it comes to deals on Washington, D.C.-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.-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 Washington, D.C. to Ontario

Have a flexible travel schedule? Discover the best time to fly to Ontario from Washington, D.C. with our price prediction graph.
Estimated round-trip price
Rates are based on past data. Find the cheapest month and day to book your flight based on your travel requirements, then search for cheap deals.

Cheapflights Insights

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

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

Use this chart to determine the optimal time to book a round-trip flight from Washington, D.C. to Ontario. Price data was last updated on March 21, 2025.

The best time to book flights from Washington, D.C. to Ontario is 77 days before your desired departure date. The cost of your flight will likely increase significantly if you book two weeks in advance of your flight.

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

Currently, August is the cheapest month in which you can book a flight from Washington, D.C. to Ontario (average of $246). Flying from Washington, D.C. to Ontario in March is currently the most expensive (average of $324). 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 WAS to ONT?

Find hourly flight availability from Washington, D.C. to Ontario. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated March 25, 2025.

It’s typically best to fly out from Washington, D.C. to Ontario in the afternoon. Doing so could potentially save you 16% on the flight price compared to flying in the evening, which is usually more expensive.

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

Use this chart to determine the cheapest time to fly round-trip from Washington, D.C. to Ontario. Price data was last updated on December 16, 2024.

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

Rainfall in Ontario by month

Plan your trip to Ontario by taking into account the average rainfall totals by month.

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.

Temperature in Ontario by month

Plan your trip to Ontario by taking into account the average temperature totals by month.

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).

Reviews of airlines servicing Ontario

Get insights into the airlines that provide service to Ontario. 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 Ontario. Reviews last updated March 25, 2025.
See what other customers who have flown with Alaska Airlines, Southwest and Delta from Washington, D.C. to Ontario have to say. In addition to providing an overall rating, users have also rated airlines in terms of entertainment options, comfort, food, crew/service, and boarding process.
Alaska Airlines
8.0
Very good
9,782 reviews

Boarding

8.2

Crew

8.5

Comfort

7.9

Entertainment

7.1

Food

7.1

Overall

8.0

Reviews

1 / 20
10.0
Excellent

Seleste,Dec 2024

FAT - SAN

The attention and efficiency of the staff and the good handling of the pilot
Alaska Airlines
8.0
Very good
9,782 reviews
Alaska Airlines
8.0
Very good
9,782 reviews

Boarding

8.2

Crew

8.5

Comfort

7.9

Entertainment

7.1

Food

7.1

Overall

8.0

Reviews

1 / 20
10.0
Excellent

Seleste,Dec 2024

FAT - SAN

The attention and efficiency of the staff and the good handling of the pilot
Southwest
8.0
Very good
4,272 reviews
Alaska Airlines
8.0
Very good
9,782 reviews

Boarding

8.2

Crew

8.5

Comfort

7.9

Entertainment

7.1

Food

7.1

Overall

8.0

Reviews

1 / 20
10.0
Excellent

Seleste,Dec 2024

FAT - SAN

The attention and efficiency of the staff and the good handling of the pilot
Delta
8.0
Very good
7,890 reviews
Alaska Airlines
8.0
Very good
9,782 reviews

Boarding

8.2

Crew

8.5

Comfort

7.9

Entertainment

7.1

Food

7.1

Overall

8.0

Reviews

1 / 20
10.0
Excellent

Seleste,Dec 2024

FAT - SAN

The attention and efficiency of the staff and the good handling of the pilot
Hawaiian Airlines
7.9
Good
2,330 reviews
Alaska Airlines
8.0
Very good
9,782 reviews

Boarding

8.2

Crew

8.5

Comfort

7.9

Entertainment

7.1

Food

7.1

Overall

8.0

Reviews

1 / 20
10.0
Excellent

Seleste,Dec 2024

FAT - SAN

The attention and efficiency of the staff and the good handling of the pilot
United Airlines
7.4
Good
8,605 reviews
Alaska Airlines
8.0
Very good
9,782 reviews

Boarding

8.2

Crew

8.5

Comfort

7.9

Entertainment

7.1

Food

7.1

Overall

8.0

Reviews

1 / 20
10.0
Excellent

Seleste,Dec 2024

FAT - SAN

The attention and efficiency of the staff and the good handling of the pilot

Related info for your journey

Find useful and relevant information for your journey from Washington, D.C. to Ontario. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.

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

    Located just 3.1 mi from the city center, Ontario is the airport most travelers will use when flying to Ontario from Washington, D.C.. Booking flights from Washington, D.C. to Ontario (ONT) should be relatively easy as there are 0 daily inbound flights from Washington, D.C. from 5 different airlines.

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

    Cheapflights users have booked flights from Washington, D.C. to Ontario round-trip from $276. Other airlines that can offer you cheap pricing are Frontier, from $278, and United Airlines, from $306. Users have found that Delta is 28% cheaper than the other options available to this destination.

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

    The cheapest airlines for a one-way flight from Washington, D.C. to Ontario are American Airlines ($102), Alaska Airlines ($114), and United Airlines ($117).

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

    The most popular route from Washington, D.C. to Ontario is Washington, D.C. Dulles Intl - Ontario. You may also consider Baltimore/Washington - Ontario or Washington, D.C. Reagan-National - Ontario.

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

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

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

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

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

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

    Currently, August is the cheapest month in which you can book a flight from Washington, D.C. to Ontario (average of $246). Flying from Washington, D.C. to Ontario in March is currently the most expensive (average of $324). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

See more FAQs

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Alternative routes for Washington, D.C. to Ontario

See prices for flight routes from nearby airports that may be better suited for you.
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Top 5 airlines flying from Washington, D.C. to Ontario

Discover the top 5 airlines that operate flights from Washington, D.C. to Ontario. 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 25, 2025.
AirlineCheapestAverageFlexibilityOn-time
FrontierCheapest$150Average$258FlexibilityNo cancel feeOn-time62%
United AirlinesCheapest$195Average$485FlexibilityNo cancel feeOn-time69%
DeltaCheapest$286Average$441FlexibilityNo cancel feeOn-timeN/A
American AirlinesCheapest$286Average$475FlexibilityNo cancel feeOn-time71%
SouthwestCheapest$326Average$528FlexibilityNo cancel feeOn-time63%
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