$154 Cheap Delta flights Baltimore (BWI) to Ontario (ONT)

View $154 flight on Tue, Nov 4, 2025Opens in a new window

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$154 Cheap Delta flights Baltimore (BWI) to Ontario (ONT)

Prices were available within the past 7 days and start at $154 for one-way flights and $302 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

Delta
Tue, Oct 14 - Tue, Oct 21
BWI
Baltimore
ONT
Ontario
$302 Roundtrip, found 2 hours ago
$302
Roundtrip
found 2 hours ago
Select Delta flight, departing Tue, Oct 14 from Baltimore to Ontario, returning Tue, Oct 21, priced at $302 found 2 hours ago
Delta
Tue, Aug 12 - Tue, Aug 19
BWI
Baltimore
ONT
Ontario
$307 Roundtrip, just found
$307
Roundtrip
just found
Select Delta flight, departing Tue, Aug 12 from Baltimore to Ontario, returning Tue, Aug 19, priced at $307 just found
Flights from Baltimore (BWI) to Ontario (ONT)
Origin airport
Baltimore Washington Intl. Thurgood Marshall
Destination airport
Los Angeles - Ontario Intl.
Airlines serving
Alaska Airlines, American Airlines, Delta, Frontier Airlines, Hawaiian Airlines, Southwest Airlines, United
Popular airline
Southwest Airlines
Distance
2277 mi
Average flight time
4 hours 1 min

Frequently asked questions

How much is a Delta Air Lines flight from Baltimore Washington Intl. Thurgood Marshall Airport (BWI) to Los Angeles - Ontario Intl. Airport (ONT)?
You'll discover budget-friendly return Delta Air Lines flights from $302 from BWI to ONT by filtering your results from "Price (lowest to highest)" on Expedia. Or look for bargains from $154 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 BWI to ONT with Delta Air Lines?
Browse for one-way or round-trip flights to Ontario in January or April. You could find a cheap fare with Delta Air Lines during these quieter months.
What is the cheapest time to book flights from Baltimore Washington Intl. Thurgood Marshall Airport (BWI) to Los Angeles - Ontario Intl. Airport (ONT) with Delta Air Lines?
Look for cheap Delta Air Lines flights from Baltimore Washington Intl. Thurgood Marshall Airport (BWI) to Los Angeles - Ontario Intl. Airport (ONT) one to three months before your departure day. Travelers who book domestic flights 34 to 86 days in advance can save 25% compared to those who book just 6 to 12 days ahead. No matter the fare type and itinerary, the best day to book a domestic flight is usually Sunday and the most expensive day is typically Monday. Passengers who book on a Sunday can save 6% on average compared to those who book their travel on a Monday.**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 Baltimore Washington Intl. Thurgood Marshall Airport (BWI) to Los Angeles - Ontario Intl. Airport (ONT)?
Fill in your dates, press search and tick the "Nonstop" filter on Expedia to find any direct flights from BWI to ONT with Delta Air Lines or other airlines.
What is the earliest Delta Air Lines flight from BWI to ONT?
Browse Delta Air Lines's earliest flights from BWI to ONT by using our "Morning" and "Early Morning" filters. Not only will you get to where you're going 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?
Delta Air Lines flights from Baltimore Washington Intl. Thurgood Marshall Airport (BWI) to Ontario touch down at Los Angeles - Ontario Intl. Airport (ONT). This is the main gateway to this city.
Why fly with Delta Air Lines from BWI to ONT?
Delta Air Lines makes flying from BWI to ONT enjoyable with a rewarding loyalty program and an excellent in-flight experience. You could even start collecting points with Delta SkyMiles. Be sure to join Expedia's free One Key™ rewards program to earn OneKeyCash™*, which can be redeemed on 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 Baltimore Washington Intl. Thurgood Marshall Airport (BWI) to Los Angeles - Ontario Intl. Airport (ONT)?
Depending on the type of fare you purchased, a fee is typically charged if you cancel or reschedule your flight more than 24 hours after it's been confirmed. To secure flexible fares, select our "No cancel fee" or "Changes included" filter when searching for flights. For more details on modifying or canceling your reservation, visit "Trips," select your flight and tick "Manage Booking."

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