$114 Cheap Flights from Baltimore (BWI) to Ontario (ONT)

View $114 flight on Mon, May 12, 2025Opens in a new window

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Find available prices by choosing your travel dates.

Cheap Flights from Baltimore to Ontario (BWI-ONT)

Prices were available within the past 7 days and start at $114 for one-way flights and $218 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

Frontier Airlines
Mon, May 19 - Sat, Jun 7
BWI
Baltimore
ONT
Ontario
$218 Roundtrip, found 1 day ago
$218
Roundtrip
found 1 day ago
Select Frontier Airlines flight, departing Mon, May 19 from Baltimore to Ontario, returning Sat, Jun 7, priced at $218 found 1 day ago
Frontier Airlines
Fri, May 16 - Mon, May 19
BWI
Baltimore
ONT
Ontario
$228 Roundtrip, found 3 hours ago
$228
Roundtrip
found 3 hours ago
Select Frontier Airlines flight, departing Fri, May 16 from Baltimore to Ontario, returning Mon, May 19, priced at $228 found 3 hours ago
Frontier Airlines
Fri, May 16 - Sat, May 31
BWI
Baltimore
ONT
Ontario
$238 Roundtrip, found 17 hours ago
$238
Roundtrip
found 17 hours ago
Select Frontier Airlines flight, departing Fri, May 16 from Baltimore to Ontario, returning Sat, May 31, priced at $238 found 17 hours ago
Frontier Airlines
Fri, May 16 - Mon, Jun 2
BWI
Baltimore
ONT
Ontario
$248 Roundtrip, found 17 hours ago
$248
Roundtrip
found 17 hours ago
Select Frontier Airlines flight, departing Fri, May 16 from Baltimore to Ontario, returning Mon, Jun 2, priced at $248 found 17 hours ago
Frontier Airlines
Fri, May 23 - Sat, May 31
BWI
Baltimore
ONT
Ontario
$250 Roundtrip, found 5 days ago
$250
Roundtrip
found 5 days ago
Select Frontier Airlines flight, departing Fri, May 23 from Baltimore to Ontario, returning Sat, May 31, priced at $250 found 5 days ago
Frontier Airlines
Fri, May 16 - Sat, May 24
BWI
Baltimore
ONT
Ontario
$258 Roundtrip, found 17 hours ago
$258
Roundtrip
found 17 hours ago
Select Frontier Airlines flight, departing Fri, May 16 from Baltimore to Ontario, returning Sat, May 24, priced at $258 found 17 hours ago
Frontier Airlines
Fri, May 16 - Thu, May 29
BWI
Baltimore
ONT
Ontario
$268 Roundtrip, found 17 hours ago
$268
Roundtrip
found 17 hours ago
Select Frontier Airlines flight, departing Fri, May 16 from Baltimore to Ontario, returning Thu, May 29, priced at $268 found 17 hours ago
Frontier Airlines
Fri, May 9 - Thu, May 22
BWI
Baltimore
ONT
Ontario
$270 Roundtrip, found 20 hours ago
$270
Roundtrip
found 20 hours ago
Select Frontier Airlines flight, departing Fri, May 9 from Baltimore to Ontario, returning Thu, May 22, priced at $270 found 20 hours ago
Frontier Airlines
Mon, Jun 9 - Fri, Jun 13
BWI
Baltimore
ONT
Ontario
$273 Roundtrip, found 4 days ago
$273
Roundtrip
found 4 days ago
Select Frontier Airlines flight, departing Mon, Jun 9 from Baltimore to Ontario, returning Fri, Jun 13, priced at $273 found 4 days ago
Frontier Airlines
Fri, May 16 - Tue, May 20
BWI
Baltimore
ONT
Ontario
$275 Roundtrip, found 16 hours ago
$275
Roundtrip
found 16 hours ago
Select Frontier Airlines flight, departing Fri, May 16 from Baltimore to Ontario, returning Tue, May 20, priced at $275 found 16 hours ago
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
Roundtrip price
$218
Distance
2277 mi

Baltimore to Ontario Flights

The cheapest times to fly from Baltimore 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 Baltimore to Ontario are during the month of May. You can find some of the cheapest flights from Baltimore to Ontario with Expedia's search tool and vast selection of airlines.

 

The best time to book a flight from Baltimore to Ontario

Sunday is one of the best days to book for cheap flights from Baltimore 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 Baltimore 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 Baltimore to Ontario in 2025. You can also book with separate airlines for your outbound and return journeys, from $114 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 Baltimore 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 Baltimore 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 Baltimore Washington Intl. Thurgood Marshall Airport (BWI) to Los Angeles - Ontario Intl. Airport (ONT) cost?
Discover the latest flight deals from BWI 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 BWI to ONT?
The cheapest flights from BWI 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 BWI to ONT?
With prices starting from $169 for a one-way journey from BWI to ONT, Southwest Airlines is currently the cheapest airline operating this route. This fare is based on the lowest price found on Expedia departing within the next three months. The flight takes off from BWI on July 19 2025. Prices were last updated on April 27 2025 and have not changed since.
How many flights per day from Baltimore Washington Intl. Thurgood Marshall Airport (BWI) to Los Angeles - Ontario Intl. Airport (ONT)?
Direct flights from Baltimore Washington Intl. Thurgood Marshall Airport (BWI) 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 Expedia’s filter tool. Enter your dates and click on either “1 Stop” or “2+ Stops.”
What day of the week has the most flights from BWI to ONT?
Usually you’ll find the most flight options available on a Friday. Tuesdays tend to be the quietest.* However, this can vary depending on the airline, season and other factors.*Busiest/quietest day to travel is based on Expedia flight demand through January to December 2024.
What is the best time to fly from Baltimore Washington Intl. Thurgood Marshall Airport (BWI) to Los Angeles - Ontario Intl. Airport (ONT)?
To reach Los Angeles - Ontario Intl. Airport (ONT) on time, book a flight that leaves from Baltimore Washington Intl. Thurgood Marshall Airport (BWI) before 3 PM. The likelihood of cancellations is 22% higher, on average, for departures after this time.**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 Baltimore Washington Intl. Thurgood Marshall Airport (BWI)?
If you’re traveling on a direct flight from Baltimore Washington Intl. Thurgood Marshall Airport (BWI) to Ontario, Los Angeles Intl. Airport (LAX) is the only airport you can land at.
Is it cheaper to buy a plane ticket from Baltimore Washington Intl. Thurgood Marshall Airport (BWI) to Los Angeles - Ontario Intl. Airport (ONT) last-minute?
Waiting until right before your break to book your flight from BWI to ONT often results in higher prices. While you may come across some last-minute deals, they’re not always guaranteed. Be flexible with your itinerary for a better chance of landing a bargain.
Is it cheaper to book a BWI to ONT flight and hotel package?
You’ll generally save money by booking a BWI 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 easy to manage everything in one convenient place. After choosing your preferred accommodations and flights, consider other add-ons like activities, tours and car rentals.
Can I cancel or change the date of my flight from Baltimore Washington Intl. Thurgood Marshall Airport (BWI) to Los Angeles - Ontario Intl. Airport (ONT)?
It’s usually possible to reschedule or cancel your BWI to ONT flight. However, if it’s been more than 24 hours since booking, additional charges may apply. Refer to your airline’s policies in your itinerary to see what changes are allowed and whether any costs are involved. You’ll also find more information on our Customer Service portal.

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*Available to One Key members.