$160 Cheap Delta flights Ontario (ONT) to Washington (IAD)

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$160 Cheap Delta flights Ontario (ONT) to Washington (IAD)

Prices were available within the past 7 days and start at $160 for one-way flights and $291 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

Delta
Tue, Feb 17 - Fri, Feb 20
ONT
Ontario
IAD
Washington
$291 Roundtrip, found 1 day ago
$291
Roundtrip
found 1 day ago
Select Delta flight, departing Tue, Feb 17 from Ontario to Washington, returning Fri, Feb 20, priced at $291 found 1 day ago
Delta
Thu, Jan 8 - Mon, Jan 12
ONT
Ontario
IAD
Washington
$307 Roundtrip, found 1 hour ago
$307
Roundtrip
found 1 hour ago
Select Delta flight, departing Thu, Jan 8 from Ontario to Washington, returning Mon, Jan 12, priced at $307 found 1 hour ago
Delta
Wed, Feb 11 - Wed, Feb 18
ONT
Ontario
IAD
Washington
$313 Roundtrip, found 3 days ago
$313
Roundtrip
found 3 days ago
Select Delta flight, departing Wed, Feb 11 from Ontario to Washington, returning Wed, Feb 18, priced at $313 found 3 days ago
Delta
Wed, Dec 17 - Tue, Jan 6
ONT
Ontario
IAD
Washington
$327 Roundtrip, found 7 hours ago
$327
Roundtrip
found 7 hours ago
Select Delta flight, departing Wed, Dec 17 from Ontario to Washington, returning Tue, Jan 6, priced at $327 found 7 hours ago
Delta
Wed, Dec 17 - Mon, Jan 5
ONT
Ontario
IAD
Washington
$347 Roundtrip, found 7 hours ago
$347
Roundtrip
found 7 hours ago
Select Delta flight, departing Wed, Dec 17 from Ontario to Washington, returning Mon, Jan 5, priced at $347 found 7 hours ago
Delta
Wed, Jan 28 - Sun, Feb 1
ONT
Ontario
IAD
Washington
$355 Roundtrip, found 2 hours ago
$355
Roundtrip
found 2 hours ago
Select Delta flight, departing Wed, Jan 28 from Ontario to Washington, returning Sun, Feb 1, priced at $355 found 2 hours ago
Delta
Fri, Jan 9 - Sun, Jan 11
ONT
Ontario
IAD
Washington
$362 Roundtrip, found 1 hour ago
$362
Roundtrip
found 1 hour ago
Select Delta flight, departing Fri, Jan 9 from Ontario to Washington, returning Sun, Jan 11, priced at $362 found 1 hour ago
Delta
Sun, Jan 11 - Tue, Jan 13
ONT
Ontario
IAD
Washington
$367 Roundtrip, found 1 hour ago
$367
Roundtrip
found 1 hour ago
Select Delta flight, departing Sun, Jan 11 from Ontario to Washington, returning Tue, Jan 13, priced at $367 found 1 hour ago
Delta
Mon, Jan 5 - Wed, Jan 14
ONT
Ontario
IAD
Washington
$376 Roundtrip, found 1 hour ago
$376
Roundtrip
found 1 hour ago
Select Delta flight, departing Mon, Jan 5 from Ontario to Washington, returning Wed, Jan 14, priced at $376 found 1 hour ago
Flights from Ontario (ONT) to Washington (IAD)
Origin airport
Los Angeles - Ontario Intl.
Destination airport
Washington Dulles Intl.
Airlines serving
Alaska Airlines, American Airlines, Delta, Frontier Airlines, Southwest Airlines, United
Popular airline
American Airlines
Distance
2236 mi

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Frequently asked questions

How much is a Delta Air Lines flight from Los Angeles - Ontario Intl. Airport (ONT) to Washington Dulles Intl. Airport (IAD)?
You'll discover cheap return Delta Air Lines flights from $291 from ONT to IAD by filtering your results from "Price (lowest to highest)" on Expedia. Or look for deals from $160 for a one-way trip.**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 ONT to IAD with Delta Air Lines?
Browse for return or one-way flights to Washington in January or February. You could find an affordable fare with Delta Air Lines during these off-season months.
What is the cheapest time to book flights from Los Angeles - Ontario Intl. Airport (ONT) to Washington Dulles Intl. Airport (IAD) with Delta Air Lines?
For cheap Delta Air Lines fares from Los Angeles - Ontario Intl. Airport (ONT) to Washington Dulles Intl. Airport (IAD), start searching one to three months before your planned departure. Securing domestic flights 34 to 86 days in advance could save you 25% compared to booking just 6 to 12 days ahead. The day you book can also impact how much you pay. Sunday is typically the cheapest, while Monday is often the most expensive for domestic flights. You can save 6% on average by booking your trip on a Sunday.**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 Los Angeles - Ontario Intl. Airport (ONT) to Washington Dulles Intl. Airport (IAD)?
Use our "Nonstop" filter when searching for direct Delta Air Lines flights from ONT to IAD. It's also an easy way to compare other airlines servicing the same nonstop journey.
What is the earliest Delta Air Lines flight from ONT to IAD?
To find the earliest departure from ONT to IAD with Delta Air Lines, sort your results by "Morning" and "Early Morning." Booking an early flight usually means cancellations are less likely.**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 Washington?
Hop on a Delta Air Lines flight from Los Angeles - Ontario Intl. Airport (ONT) to Washington, and you'll most likely land at Washington Dulles Intl. Airport (IAD). This is the airline's main hub here.
Why fly with Delta Air Lines from ONT to IAD?
With a rewarding loyalty program and an excellent in-flight experience, Delta Air Lines is a top choice for many passengers flying from ONT to IAD. Plus, if you're a Delta SkyMiles and One Key™ member booking through Expedia, you could earn OneKeyCash™* on eligible flights on top of your airline miles, which can go toward future travel.*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 Los Angeles - Ontario Intl. Airport (ONT) to Washington Dulles Intl. Airport (IAD)?
Depending on your fare type, a fee may apply if you modify or cancel your flight more than 24 hours after confirmation. To secure flexible plane tickets, select our "Changes included" and "No cancel fee" boxes while searching for flights. For additional information on canceling or modifying your reservation, visit "Trips," select your flight and click on "Manage Booking."

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