$150 Cheap Flights from Baltimore (BWI) to Ontario (ONT)

View $150 flight on Wed, Aug 13, 2025Opens in a new window

Popular airlines from Baltimore Washington Intl. Airport (BWI) to Los Angeles - Ontario Intl. Airport (ONT)

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Cheap Flights from Baltimore to Ontario (BWI-ONT)

Prices were available within the past 7 days and start at $150 for one-way flights and $179 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

Southwest Airlines
Tue, Sep 23 - Tue, Sep 30
BWI
Baltimore
ONT
Ontario
$179 Roundtrip, found 3 days ago
$179
Roundtrip
found 3 days ago
Select Southwest Airlines flight, departing Tue, Sep 23 from Baltimore to Ontario, returning Tue, Sep 30, priced at $179 found 3 days ago
Southwest Airlines
Tue, Sep 23 - Tue, Sep 30
BWI
Baltimore
ONT
Ontario
$184 Roundtrip, found 3 days ago
$184
Roundtrip
found 3 days ago
Select Southwest Airlines flight, departing Tue, Sep 23 from Baltimore to Ontario, returning Tue, Sep 30, priced at $184 found 3 days ago
Southwest Airlines
Tue, Sep 9 - Sat, Sep 13
BWI
Baltimore
ONT
Ontario
$191 Roundtrip, found 3 days ago
$191
Roundtrip
found 3 days ago
Select Southwest Airlines flight, departing Tue, Sep 9 from Baltimore to Ontario, returning Sat, Sep 13, priced at $191 found 3 days ago
American Airlines
Tue, Sep 23 - Tue, Sep 30
BWI
Baltimore
ONT
Ontario
$194 Roundtrip, found 3 days ago
$194
Roundtrip
found 3 days ago
Select American Airlines flight, departing Tue, Sep 23 from Baltimore to Ontario, returning Tue, Sep 30, priced at $194 found 3 days ago
Southwest Airlines
Sat, Sep 20 - Sat, Sep 27
BWI
Baltimore
ONT
Ontario
$199 Roundtrip, found 4 days ago
$199
Roundtrip
found 4 days ago
Select Southwest Airlines flight, departing Sat, Sep 20 from Baltimore to Ontario, returning Sat, Sep 27, priced at $199 found 4 days ago
Southwest Airlines
Mon, Aug 25 - Mon, Sep 1
BWI
Baltimore
ONT
Ontario
$204 Roundtrip, found 3 days ago
$204
Roundtrip
found 3 days ago
Select Southwest Airlines flight, departing Mon, Aug 25 from Baltimore to Ontario, returning Mon, Sep 1, priced at $204 found 3 days ago
Southwest Airlines
Mon, Aug 25 - Mon, Sep 1
BWI
Baltimore
ONT
Ontario
$206 Roundtrip, found 3 days ago
$206
Roundtrip
found 3 days ago
Select Southwest Airlines flight, departing Mon, Aug 25 from Baltimore to Ontario, returning Mon, Sep 1, priced at $206 found 3 days ago
United
Sat, Aug 30 - Sun, Aug 31
BWI
Baltimore
ONT
Ontario
$224 Roundtrip, found 6 days ago
$224
Roundtrip
found 6 days ago
Select United flight, departing Sat, Aug 30 from Baltimore to Ontario, returning Sun, Aug 31, priced at $224 found 6 days ago
Alaska Airlines
Tue, Sep 23 - Tue, Sep 30
BWI
Baltimore
ONT
Ontario
$264 Roundtrip, found 3 days ago
$264
Roundtrip
found 3 days ago
Select Alaska Airlines flight, departing Tue, Sep 23 from Baltimore to Ontario, returning Tue, Sep 30, priced at $264 found 3 days ago
Frontier Airlines
Wed, Aug 6 - Fri, Aug 8
BWI
Baltimore
ONT
Ontario
$295 Roundtrip, found 2 days ago
$295
Roundtrip
found 2 days ago
Select Frontier Airlines flight, departing Wed, Aug 6 from Baltimore to Ontario, returning Fri, Aug 8, priced at $295 found 2 days ago

Find the cheapest month to fly from Baltimore (BWI) to Ontario (ONT)

October is typically the cheapest month to fly

From $158 - $581 per traveler.

Graph displaying average flight prices per month

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
$178
Distance
2277 mi
Average flight time
3 hours 41 mins

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 September. 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 $150 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?
You can land cheap return flights from Baltimore Washington Intl. Thurgood Marshall Airport (BWI) to Los Angeles - Ontario Intl. Airport (ONT) starting at $152. Book your seat and start your adventure. This information is based on the cheapest price found on Expedia for this return journey departing within the next three months. This airfare is for a Southwest Airlines and Spirit Airlines flight leaving BWI on August 9 2025 and touching down at ONT. The price was last updated on July 13 2025 and has not changed since.
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 $102 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 October 2 2025. Prices were last updated on July 13 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.