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£132 Cheap Flights from Ontario Intl. Airport (ONT) to Baltimore (BWI)

View £132 flight on Mon, 17 Aug 2026Opens in a new window

Popular airlines from Ontario Intl. Airport (ONT) to Baltimore Washington International Airport (BWI)

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Cheap Flights from Ontario Intl. Airport (ONT) to Baltimore (BWI)

Prices were available within the past 7 days and start at £132 for one-way flights and £379 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

Delta
Thu, 10 Sept - Sun, 20 Sept
ONT
Ontario
BWI
Baltimore
£379 Return, found 4 hours ago
£379
Return
found 4 hours ago
Select Delta flight, departing Thu, 10 Sept from Ontario to Baltimore, returning Sun, 20 Sept, priced at £379 found 4 hours ago
Delta
Mon, 7 Sept - Sun, 20 Sept
ONT
Ontario
BWI
Baltimore
£409 Return, found 4 hours ago
£409
Return
found 4 hours ago
Select Delta flight, departing Mon, 7 Sept from Ontario to Baltimore, returning Sun, 20 Sept, priced at £409 found 4 hours ago
Delta
Tue, 18 Aug - Thu, 20 Aug
ONT
Ontario
BWI
Baltimore
£457 Return, found 4 hours ago
£457
Return
found 4 hours ago
Select Delta flight, departing Tue, 18 Aug from Ontario to Baltimore, returning Thu, 20 Aug, priced at £457 found 4 hours ago
Alaska Airlines
Thu, 20 Aug - Wed, 26 Aug
ONT
Ontario
BWI
Baltimore
£513 Return, found 2 days ago
£513
Return
found 2 days ago
Select Alaska Airlines flight, departing Thu, 20 Aug from Ontario to Baltimore, returning Wed, 26 Aug, priced at £513 found 2 days ago
Alaska Airlines
Thu, 20 Aug - Wed, 26 Aug
ONT
Ontario
BWI
Baltimore
£572 Return, found 2 days ago
£572
Return
found 2 days ago
Select Alaska Airlines flight, departing Thu, 20 Aug from Ontario to Baltimore, returning Wed, 26 Aug, priced at £572 found 2 days ago
Alaska Airlines
Tue, 4 Aug - Mon, 10 Aug
ONT
Ontario
BWI
Baltimore
£591 Return, found 4 days ago
£591
Return
found 4 days ago
Select Alaska Airlines flight, departing Tue, 4 Aug from Ontario to Baltimore, returning Mon, 10 Aug, priced at £591 found 4 days ago
Alaska Airlines
Thu, 20 Aug - Wed, 26 Aug
ONT
Ontario
BWI
Baltimore
£616 Return, found 2 days ago
£616
Return
found 2 days ago
Select Alaska Airlines flight, departing Thu, 20 Aug from Ontario to Baltimore, returning Wed, 26 Aug, priced at £616 found 2 days ago
Alaska Airlines
Tue, 4 Aug - Mon, 10 Aug
ONT
Ontario
BWI
Baltimore
£629 Return, found 4 days ago
£629
Return
found 4 days ago
Select Alaska Airlines flight, departing Tue, 4 Aug from Ontario to Baltimore, returning Mon, 10 Aug, priced at £629 found 4 days ago
Alaska Airlines
Tue, 4 Aug - Mon, 10 Aug
ONT
Ontario
BWI
Baltimore
£719 Return, found 4 days ago
£719
Return
found 4 days ago
Select Alaska Airlines flight, departing Tue, 4 Aug from Ontario to Baltimore, returning Mon, 10 Aug, priced at £719 found 4 days ago
Alaska Airlines
Tue, 4 Aug - Mon, 10 Aug
ONT
Ontario
BWI
Baltimore
£757 Return, found 4 days ago
£757
Return
found 4 days ago
Select Alaska Airlines flight, departing Tue, 4 Aug from Ontario to Baltimore, returning Mon, 10 Aug, priced at £757 found 4 days ago

Frequently asked questions

How much does a flight from Ontario Intl. Airport (ONT) to Baltimore, MD (BWI-Baltimore Washington Intl. Thurgood Marshall) cost?
You can find cheap one-way flights from £132 and cheap return flights from £379 ONT to BWI with Expedia. One-way flights typically cost between £204 and £450. Flight prices vary based on the month and day of the week you want to travel, as well as the airline and how far in advance you book your ticket. Filter your search on Expedia by "Price (lowest to highest)" to see the cheapest fares first, and use the Price Tracking tool to receive alerts when ONT to BWI ticket fares go up or down.
What is the cheapest month to fly from Ontario Intl. Airport (ONT) to Baltimore, MD (BWI-Baltimore Washington Intl. Thurgood Marshall)?
September is typically the cheapest month to fly from Ontario Intl. Airport (ONT) to Baltimore, MD (BWI-Baltimore Washington Intl. Thurgood Marshall), with average return fares around £298. September often sees lower prices as the summer travel rush ends and before the holiday season begins, leading to reduced demand. Other cheap months to fly from Ontario Intl. Airport (ONT) to Baltimore, MD (BWI-Baltimore Washington Intl. Thurgood Marshall) include February and August.
Which airlines fly direct from Ontario Intl. Airport (ONT) to Baltimore, MD (BWI-Baltimore Washington Intl. Thurgood Marshall)?
Only one airline offers direct flights from Ontario Intl. Airport (ONT) to Baltimore, MD (BWI-Baltimore Washington Intl. Thurgood Marshall). Southwest Airlines operates 7 direct flights from ONT to BWI every week.
How do I find cheap flights from Ontario Intl. Airport (ONT) to Baltimore, MD (BWI)?
To find a cheap flight from Ontario Intl. Airport (ONT) to Baltimore, MD (BWI), be flexible with your dates. Traveling outside of peak vacation months and booking a mid-week flight can help you save. Early morning and late night flights are often more affordable, too. Expedia allows you to compare flight times, airlines and routes all in one place to find low fares. You can also set up Price Tracking and receive alerts when fares go up or down.
What is the best time to fly from Ontario Intl. Airport (ONT) to Baltimore, MD (BWI-Baltimore Washington Intl. Thurgood Marshall)?
The cheapest months to fly from Ontario Intl. Airport (ONT) to Baltimore Washington Intl. Thurgood Marshall (BWI) are typically September and August, with average return flights around £298. These months can offer a good balance of more affordable fares before the busy holiday season and still pleasant weather for travel.
What is the earliest flight from Ontario Intl. Airport (ONT) to Baltimore, MD (BWI-Baltimore Washington Intl. Thurgood Marshall)?
The earliest flight from Ontario Intl. Airport (ONT) to Baltimore, MD (BWI-Baltimore Washington Intl. Thurgood Marshall) typically departs around 12:55 AM. This service is operated by American Airlines and is a seasonal service, active only in September. An early departure like this can be really handy if you want to maximise your time at your destination. To compare early flights on Expedia, select the "Early Morning" and "Morning" filters in your search.
How long does it take to fly from Ontario Intl. Airport (ONT) to Baltimore, MD (BWI-Baltimore Washington Intl. Thurgood Marshall)?
When flying from Ontario Intl. Airport (ONT) to Baltimore, MD (BWI-Baltimore Washington Intl. Thurgood Marshall), you'll cover a distance of approximately 3,664 kilometers. A non-stop flight typically takes around 4 hours 48 minutes. If you opt for a flight with one stop, your journey will usually be longer, taking about 7 hours 18 minutes. Flights with two or more stops will extend your travel time further, typically to around 12 hours 48 minutes. Keep in mind that actual flight times can vary due to factors like wind patterns and air traffic.
Can you fly business or first class from Ontario Intl. Airport (ONT) to Baltimore, MD (BWI)?
Select the "Business class" and "First class" filters when looking for Ontario Intl. Airport (ONT) to Baltimore, MD (BWI) flights on Expedia. This is the easiest way to compare prices, routes and flight times for your trip.
How do I earn miles on a Ontario Intl. Airport (ONT) to Baltimore, MD (BWI-Baltimore Washington Intl. Thurgood Marshall) flight with Expedia?
It's easy to earn miles on a Ontario Intl. Airport (ONT) to Baltimore, MD (BWI-Baltimore Washington Intl. Thurgood Marshall) flight when you book with Expedia. Before you confirm your booking, simply select your frequent flyer program and enter your program number. As a member of One Key™, you can also earn OneKeyCash™* on top of your airline miles when you book with Expedia.*Excludes taxes and fees. OneKeyCash is not redeemable for cash and can only be used on Expedia and other participating brands.
What airports do you fly into for Baltimore, MD (BWI) from Ontario Intl. Airport (ONT)?
If you're planning to travel to Baltimore from Los Angeles - Ontario Intl. (ONT), you can fly directly into Baltimore Washington Intl. Thurgood Marshall (BWI). Some flights may connect through major hubs like Denver Intl. (DEN), Midway Intl. (MDW), or Harry Reid International Airport (LAS) before reaching Baltimore. Compare routes and airports on Expedia to find the best flight options for your travel plans.
Is it cheaper to buy a plane ticket from Ontario Intl. Airport (ONT) to Baltimore, MD (BWI-Baltimore Washington Intl. Thurgood Marshall) at the last minute?
Typically, booking a last minute flight from Ontario Intl. Airport (ONT) to Baltimore, MD (BWI-Baltimore Washington Intl. Thurgood Marshall) will be more expensive than booking in advance. As the departure date approaches, there are usually fewer seats available which can drive up the cost. However, if there's some wiggle room with your travel dates and times, you could bag a cheap last-minute fare.
Is it cheaper to book a Ontario Intl. Airport (ONT) to Baltimore, MD (BWI-Baltimore Washington Intl. Thurgood Marshall) flight and hotel package?
Securing a Ontario Intl. Airport (ONT) to Baltimore, MD (BWI-Baltimore Washington Intl. Thurgood Marshall) flight and hotel package is usually cheaper than booking separately. With Expedia, you can enjoy the ease of organizing your travels all in one place. Select from our extensive range of stays and then add flights, activities and car rentals to your booking. Bundle everything together, and you could save hundreds of dollars.
Can I cancel or change the date of my flight from Ontario Intl. Airport (ONT) to Baltimore, MD (BWI)?
If you booked your Ontario Intl. Airport (ONT) to Baltimore, MD (BWI) flight within the last 24 hours, you may be able to modify or cancel it without any fees. Depending on the airline and the type of ticket you have, additional charges may apply for changes beyond this timeframe. Airline policies and contact information can be found in your itinerary or confirmation email. Or, head to our Customer Service portal if you'd like more information.

Travel information

Origin airport
Ontario Intl. Airport
Destination airport
Baltimore Washington Intl. Thurgood Marshall
Return price
£379
Distance
3643 km
Average flight time
4 hours 50 mins

Book with confidence

Compare flights from Ontario Intl. Airport to Baltimore easily and book with confidence

For travelling on business or for pleasure, Expedia makes it easy to book your flights from Ontario Intl. Airport to Baltimore. Operating between them flights per day, 20 airlines cover the route. And fly direct, getting you to Baltimore Washington Intl. Thurgood Marshall in just hours. If you have a preferred carrier, use our advanced search tool to find the right flight from Ontario Intl. Airport to Baltimore Washington Intl. Thurgood Marshall.  

To make things even better, in the advanced search, you can also choose to fly economy, premium economy, business or first class, select your maximum number of stops, and pick your preferred departure and arrival time. You can also opt for refundable and direct flights. 

Grab a great deal on your flight from Ontario Intl. Airport (ONT) to Baltimore Washington Intl. Thurgood Marshall (BWI)

The easiest way to view the best deals on flights from Ontario Intl. Airport to Baltimore today is to enter your travel dates and hit search. From here, you can sort your results by price to see the cheapest flights first. Right now, return flights from Ontario Intl. Airport to Baltimore Washington Intl. Thurgood Marshall start at just £379 and range up to £757.  

To find an even better deal, try  

  • being flexible on your dates – midweek flights can be cheaper
  • looking for other airports near Ontario Intl. Airport and Baltimore
  • booking your flight during September, the cheapest month on this route
  • varying your flight times – early morning and late at night are sometimes cheaper 

Why you should book your Ontario Intl. Airport to Baltimore flight with Expedia!

We cater for all flight types, cabin classes and airlines. So whether you’re booking flights from Ontario Intl. Airport to Baltimore Washington Intl. Thurgood Marshall for a budget break or a business trip with a bit of pleasure thrown in, we make it easy to secure the seat that’s right for you.  

Thanks to our supersized inventory that offers great choice all in one place, you know you’ll get a great deal with Expedia. Especially if you bundle your flight together with your hotel, you will unlock amazing savings. For added peace of mind, you can choose flexible bookings or filter to find refundable options, so you won’t pay a fee to change your flight.  

Compare flights from Ontario Intl. Airport to Baltimore easily and book with confidence

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