$139 Cheap Delta flights Washington (DCA) to Ontario (ONT)

View $139 flight on Wed, Dec 3, 2025Opens in a new window

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$139 Cheap Delta flights Washington (DCA) to Ontario (ONT)

Prices were available within the past 7 days and start at $139 for one-way flights and $276 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

Delta
Tue, Oct 14 - Tue, Oct 21
DCA
Washington
ONT
Ontario
$276 Roundtrip, found 1 day ago
$276
Roundtrip
found 1 day ago
Select Delta flight, departing Tue, Oct 14 from Washington to Ontario, returning Tue, Oct 21, priced at $276 found 1 day ago
Delta
Tue, Oct 7 - Sat, Oct 11
DCA
Washington
ONT
Ontario
$280 Roundtrip, found 2 days ago
$280
Roundtrip
found 2 days ago
Select Delta flight, departing Tue, Oct 7 from Washington to Ontario, returning Sat, Oct 11, priced at $280 found 2 days ago
Delta
Tue, Oct 14 - Tue, Oct 21
DCA
Washington
ONT
Ontario
$282 Roundtrip, found 1 day ago
$282
Roundtrip
found 1 day ago
Select Delta flight, departing Tue, Oct 14 from Washington to Ontario, returning Tue, Oct 21, priced at $282 found 1 day ago
Delta
Tue, Nov 4 - Tue, Nov 11
DCA
Washington
ONT
Ontario
$299 Roundtrip, found 13 hours ago
$299
Roundtrip
found 13 hours ago
Select Delta flight, departing Tue, Nov 4 from Washington to Ontario, returning Tue, Nov 11, priced at $299 found 13 hours ago
Delta
Wed, Oct 8 - Sat, Nov 8
DCA
Washington
ONT
Ontario
$312 Roundtrip, found 12 hours ago
$312
Roundtrip
found 12 hours ago
Select Delta flight, departing Wed, Oct 8 from Washington to Ontario, returning Sat, Nov 8, priced at $312 found 12 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, JetBlue Airways, Southwest Airlines, United
Popular airline
American Airlines
Distance
2258 mi

Frequently asked questions

How much is a Delta Air Lines flight from Ronald Reagan Washington National Airport (DCA) to Los Angeles - Ontario Intl. Airport (ONT)?
Use the "Price (lowest to highest)" filter on Expedia to search for cheap Delta Air Lines return flights from $276 from DCA to ONT. Affordable one-way tickets from $139 are also available.**These prices were available on Expedia within the past 7 days, for flights departing within the next year. Prices and availability are subject to change. Additional terms apply.
What is the cheapest month to fly from DCA to ONT with Delta Air Lines?
Delta Air Lines flights to Ontario are often more affordable in the low-season months of January and April. Whether you're in search of a return or one-way ticket, you could find a better deal then.
What is the cheapest time to book flights from Ronald Reagan Washington National Airport (DCA) to Los Angeles - Ontario Intl. Airport (ONT) with Delta Air Lines?
Start searching one to three months ahead of your departure date to get cheap fares on Delta Air Lines flights from Ronald Reagan Washington National Airport (DCA) to Los Angeles - Ontario Intl. Airport (ONT). You can save 25% by booking your domestic flight 34 to 86 days in advance compared to last-minute reservations made 6 to 12 days out. You could also cut costs by buying your fare on a Sunday, as it's 6% cheaper on average than a Monday, the most expensive day to book.* Get your timing right, and you can enjoy significant savings on domestic trips.*Ideal booking window recommendation is based on average round-trip ticket prices for January through November for 2024. Best day of the week to book recommendation is based on average round-trip ticket prices for January through October 2024. All data sourced from ARC's global airline sales database.
Does Delta Air Lines fly nonstop from Ronald Reagan Washington National Airport (DCA) to Los Angeles - Ontario Intl. Airport (ONT)?
To find out if there's a direct trip from DCA to ONT with Delta Air Lines or any other airlines, check the "Nonstop" box when browsing for tickets.
What is the earliest Delta Air Lines flight from DCA to ONT?
Find Delta Air Lines's earliest flights from DCA to ONT by using our "Morning" and "Early Morning" filters. Not only will you get to your destination sooner, early departures also experience 20% fewer cancellations.**Most reliable time of the day recommendation is based on January through August 2024 flight status data sourced from OAG's global flight data platform.
What airports does Delta Air Lines fly into in Ontario?
Catch a Delta Air Lines flight from Ronald Reagan Washington National Airport (DCA) to Ontario, and you'll most likely arrive at Los Angeles - Ontario Intl. Airport (ONT). This is the airline's primary hub in this destination.
Why fly with Delta Air Lines from DCA to ONT?
With a rewarding loyalty program and an excellent in-flight experience, Delta Air Lines is a popular option for many travelers flying from DCA to ONT. Plus, if you're a Delta SkyMiles and One Key™ member booking with Expedia, you could earn OneKeyCash™* on eligible flights on top of your airline miles, which you can put toward future trips.*OneKeyCash™ disclaimer - OneKeyCash™ is not redeemable for cash and can only be used on Expedia, Hotels.com and Vrbo.
Can I change or cancel my Delta Air Lines flight from Ronald Reagan Washington National Airport (DCA) to Los Angeles - Ontario Intl. Airport (ONT)?
It's usually possible to modify or cancel your flight, although there may be a charge if you booked more than 24 hours ago. Need flexible options? Use our "Changes included" or "No cancel fee" filter to find flights that won't penalize you if you need to revise your plans. To update your itinerary, visit "Trips," select your flight and click on "Manage Booking" for more information.

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