$104 Cheap Flights from Washington (DCA) to Ontario (ONT)

View $104 flight on Sat, May 10, 2025Opens in a new window

Popular airlines from Ronald Reagan Washington National Airport (DCA) to Los Angeles - Ontario Intl. Airport (ONT)

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Find available prices by choosing your travel dates.

Cheap Flights from Washington to Ontario (DCA-ONT)

Prices were available within the past 7 days and start at $104 for one-way flights and $183 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

Frontier Airlines
Tue, May 6 - Wed, May 7
DCA
Washington
ONT
Ontario
$183 Roundtrip, found 1 day ago
$183
Roundtrip
found 1 day ago
Select Frontier Airlines flight, departing Tue, May 6 from Washington to Ontario, returning Wed, May 7, priced at $183 found 1 day ago
Frontier Airlines
Tue, May 20 - Sat, May 24
DCA
Washington
ONT
Ontario
$188 Roundtrip, found 8 hours ago
$188
Roundtrip
found 8 hours ago
Select Frontier Airlines flight, departing Tue, May 20 from Washington to Ontario, returning Sat, May 24, priced at $188 found 8 hours ago
Frontier Airlines
Wed, May 7 - Thu, May 8
DCA
Washington
ONT
Ontario
$193 Roundtrip, found 13 hours ago
$193
Roundtrip
found 13 hours ago
Select Frontier Airlines flight, departing Wed, May 7 from Washington to Ontario, returning Thu, May 8, priced at $193 found 13 hours ago
Frontier Airlines
Tue, Apr 29 - Fri, May 2
DCA
Washington
ONT
Ontario
$198 Roundtrip, found 19 hours ago
$198
Roundtrip
found 19 hours ago
Select Frontier Airlines flight, departing Tue, Apr 29 from Washington to Ontario, returning Fri, May 2, priced at $198 found 19 hours ago
Frontier Airlines
Tue, Apr 29 - Wed, Apr 30
DCA
Washington
ONT
Ontario
$203 Roundtrip, found 17 hours ago
$203
Roundtrip
found 17 hours ago
Select Frontier Airlines flight, departing Tue, Apr 29 from Washington to Ontario, returning Wed, Apr 30, priced at $203 found 17 hours ago
Frontier Airlines
Sat, May 10 - Wed, May 21
DCA
Washington
ONT
Ontario
$208 Roundtrip, just found
$208
Roundtrip
just found
Select Frontier Airlines flight, departing Sat, May 10 from Washington to Ontario, returning Wed, May 21, priced at $208 just found
Alaska Airlines
Tue, Jun 3 - Tue, Jun 10
DCA
Washington
ONT
Ontario
$257 Roundtrip, found 13 hours ago
$257
Roundtrip
found 13 hours ago
Select Alaska Airlines flight, departing Tue, Jun 3 from Washington to Ontario, returning Tue, Jun 10, priced at $257 found 13 hours ago
United
Wed, May 28 - Sat, Jun 7
DCA
Washington
ONT
Ontario
$263 Roundtrip, found 1 day ago
$263
Roundtrip
found 1 day ago
Select United flight, departing Wed, May 28 from Washington to Ontario, returning Sat, Jun 7, priced at $263 found 1 day ago
American Airlines
Wed, Jun 4 - Fri, Jun 6
DCA
Washington
ONT
Ontario
$278 Roundtrip, found 3 hours ago
$278
Roundtrip
found 3 hours ago
Select American Airlines flight, departing Wed, Jun 4 from Washington to Ontario, returning Fri, Jun 6, priced at $278 found 3 hours ago
Delta
Tue, Jul 8 - Fri, Jul 11
DCA
Washington
ONT
Ontario
$327 Roundtrip, found 5 hours ago
$327
Roundtrip
found 5 hours ago
Select Delta flight, departing Tue, Jul 8 from Washington to Ontario, returning Fri, Jul 11, priced at $327 found 5 hours ago
Flights from Washington (DCA) to Ontario (ONT)
Origin airport
Ronald Reagan Washington National
Destination airport
Los Angeles - Ontario Intl.
Airlines serving
Alaska Airlines, American Airlines, Delta, Frontier Airlines, Hawaiian Airlines, JetBlue Airways, Southwest Airlines, United
Roundtrip price
$182
Distance
2258 mi

Washington to Ontario Flights

The cheapest times to fly from Washington to Ontario

On average, Thursday can be the cheapest time to fly, according to data from the Airlines Reporting Corporation (ARC), one of the world's biggest databases for global airline sales. The data reveals that you could save up to 16% by flying on a Thursday—the cheapest day to travel on average—instead of a Sunday—the most expensive. Some of the most affordable flights from Washington to Ontario are during the month of May. You can find some of the cheapest flights from Washington to Ontario with Expedia's search tool and vast selection of airlines.

The best time to book a flight from Washington to Ontario

Sunday is one of the best days to book for cheap flights from Washington to Ontario: Tickets reserved on a Sunday cost between 6% and 13% less than those reserved on a Friday, according to ARC data. The data also suggests booking early can also lead to cheaper airfares. You could save 24% by buying your tickets for domestic flights at least a month in advance and 10% by booking international flights 2 months in advance.

How to find cheap round-trip tickets from Washington to Ontario

Being flexible with your dates and using Expedia's Price Drop Protection and Price Tracking features are some of the best ways of finding a cheap ticket from Washington to Ontario in 2025. You can also book with separate airlines for your outbound and return journeys, from $104 one-way. Expedia also offers Price Drop Protection, so if the cost of your airfare goes down after booking, you'll receive a credit for the difference*. This is available for a small fee, and is free to One Key Gold and Platinum tier members.

Expedia's Price Tracking feature means you can stay on top of airfares without manually checking every day. It sends you automated price alerts for cheap Washington to Ontario flights and uses historical data to indicate when the best time to book is. Download Expedia's free app to activate this handy tool in a few easy taps.

You could also save big by booking one of Expedia's vacation packages. Bundling together your Washington to Ontario airfare with your accommodations and car rental is often cheaper than booking everything separately. There’s also One Key, Expedia's generous rewards program. Join for free and you could earn One Key cash on most bookings to save on future adventures.

*Terms apply.

Disclaimer: ARC The statistics are based on average round-trip ticket prices between January and August 2023. The percentages you see are averages.

Frequently asked questions

How much does a flight from Ronald Reagan Washington National Airport (DCA) to Los Angeles - Ontario Intl. Airport (ONT) cost?
Discover the latest flight deals from DCA to ONT by entering your preferred travel dates and searching on Expedia. Easily compare prices by departure date if you have flexibility with your schedule and use handy filters to explore prices for your preferred journey. As a member of One Key™, our free loyalty program, you can use Price Tracking to watch fares and receive notifications if prices go up or down.
What is the cheapest month to fly from DCA to ONT?
The cheapest flights from DCA to ONT are usually during off-peak season, when demand is lower. To save money, avoid flying during public holidays, school breaks and major local events.
What is the cheapest airline that flies from DCA to ONT?
Use the filter tool on Expedia to compare airlines and find the cheapest carrier that’ll take you from DCA to ONT. Sort your results by “Price (lowest to highest)” to snap up a great deal.
How many flights per day from Ronald Reagan Washington National Airport (DCA) to Los Angeles - Ontario Intl. Airport (ONT)?
Nonstop flights from Ronald Reagan Washington National Airport (DCA) to Los Angeles - Ontario Intl. Airport (ONT) aren’t available daily, so you’ll need to take a flight with a layover. Explore your options with our filter tool. Enter your dates and pick either “1 Stop” or “2+ Stops.”
What day of the week has the most flights from DCA to ONT?
You’ll typically find Tuesday the quietest day for flights, while Fridays are often the busiest.* However this can change from season to season and during public holidays or peak travel times.*Busiest/quietest day to travel is based on Expedia flight demand through January to December 2024.
What is the best time to fly from Ronald Reagan Washington National Airport (DCA) to Los Angeles - Ontario Intl. Airport (ONT)?
Opt for a flight from Ronald Reagan Washington National Airport (DCA) to Los Angeles - Ontario Intl. Airport (ONT) that leaves before 3 PM to reduce the likelihood of delays. Departures after this time are on average 22% more likely to be canceled.**Most reliable time of the day and month to travel recommendation is based on January through August 2024 flight status data sourced from OAG’s global flight data platform.
What airports do you fly into for Ontario from Ronald Reagan Washington National Airport (DCA)?
Los Angeles Intl. Airport (LAX) is the only airport in Ontario with direct flights from Ronald Reagan Washington National Airport (DCA). Check out the available options and find affordable fares on Expedia.
Is it cheaper to buy a plane ticket from Ronald Reagan Washington National Airport (DCA) to Los Angeles - Ontario Intl. Airport (ONT) last-minute?
Holding off until right before your break to book a flight from DCA to ONT generally means paying more. While you might find some last-minute deals, they aren’t always guaranteed. Keep your travel schedule open for a better chance of snagging a bargain.
Is it cheaper to book a DCA to ONT flight and hotel package?
You’ll generally save money by booking a DCA to ONT flight and hotel package compared to booking separately. In fact, travelers could save hundreds of dollars by bundling with Expedia. And it’s simple to manage everything in one convenient place. After choosing your ideal accommodations and flights, consider other add-ons like tours, activities and car rentals.
Can I cancel or change the date of my flight from Ronald Reagan Washington National Airport (DCA) to Los Angeles - Ontario Intl. Airport (ONT)?
If you reserved your DCA to ONT flight within the last 24 hours, you may be able to cancel or modify it without any fees. Depending on the airline and the type of fare you purchased, additional charges may apply for changes after that time. Airline policies and contact information can be found in your itinerary or confirmation email. Or, visit our Customer Service portal for more information.

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*Available to One Key members.