£202 Cheap Flights from Ontario Intl. Airport (ONT) to Baltimore (BWI)

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Popular airlines from Los Angeles - 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 £202 for one-way flights and for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

Frequently asked questions

What is the cheapest month to fly from Ontario, CA (ONT-Los Angeles - Ontario Intl.) to Baltimore, MD (BWI-Baltimore Washington Intl. Thurgood Marshall)?
September is typically the cheapest month to fly from Ontario, CA (ONT-Los Angeles - Ontario Intl.) to Baltimore, MD (BWI-Baltimore Washington Intl. Thurgood Marshall), with average return fares of approximately £553. This is about 14% lower than the average price throughout the year. 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, CA (ONT-Los Angeles - Ontario Intl.) to Baltimore, MD (BWI-Baltimore Washington Intl. Thurgood Marshall) include February and August.
Which airlines fly direct from Ontario, CA (ONT-Los Angeles - Ontario Intl.) to Baltimore, MD (BWI-Baltimore Washington Intl. Thurgood Marshall)?
Enter ONT to BWI and your travel dates, then apply the 'Nonstop' filter to see only direct flights.
How do I find cheap flights from Ontario, CA (ONT-Los Angeles - Ontario Intl.) to Baltimore, MD (BWI-Baltimore Washington Intl. Thurgood Marshall)?
To find a cheap flight from Ontario, CA (ONT-Los Angeles - Ontario Intl.) to Baltimore, MD (BWI-Baltimore Washington Intl. Thurgood Marshall), 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 airline to fly with from Ontario, CA (ONT-Los Angeles - Ontario Intl.) to Baltimore, MD (BWI-Baltimore Washington Intl. Thurgood Marshall)?
The best airline to fly with from Ontario, CA (ONT-Los Angeles - Ontario Intl.) to Baltimore, MD (BWI-Baltimore Washington Intl. Thurgood Marshall) will differ from traveller to traveller. If you like to fly early, WN offers early morning flights. If price is the most important factor, WN typically offers the lowest fares. WN offers the most daily flights from Ontario, CA (ONT-Los Angeles - Ontario Intl.) to Baltimore, MD (BWI-Baltimore Washington Intl. Thurgood Marshall), which is brilliant if flexibility is what you value most. The best carrier for this journey could also be the one you have a loyalty membership with, as flying with that airline or another airline within the same alliance could help you collect points or enjoy lounge access.
What is the best time to fly from Ontario, CA (ONT-Los Angeles - Ontario Intl.) to Baltimore, MD (BWI-Baltimore Washington Intl. Thurgood Marshall)?
Based on booking data from the past year, the cheapest months to fly from Ontario, CA (ONT-Los Angeles - Ontario Intl.) to Baltimore, MD (BWI-Baltimore Washington Intl. Thurgood Marshall) are typically September and August, with average return flights costing around £553. These months can be a great time to find more affordable fares, allowing you to save on your trip.
How many flights per day from Ontario, CA (ONT-Los Angeles - Ontario Intl.) to Baltimore, MD (BWI-Baltimore Washington Intl. Thurgood Marshall)?
There are approximately 48 connecting flights per day from Ontario, CA (ONT-Los Angeles - Ontario Intl.) to Baltimore, MD (BWI-Baltimore Washington Intl. Thurgood Marshall). Some common connection points include Portland Intl. (PDX), Seattle - Tacoma Intl. (SEA), and Sky Harbor Intl. (PHX).
What is the earliest flight from Ontario, CA (ONT-Los Angeles - Ontario Intl.) to Baltimore, MD (BWI-Baltimore Washington Intl. Thurgood Marshall)?
The earliest flight from Ontario, CA (ONT-Los Angeles - Ontario Intl.) to Baltimore, MD (BWI-Baltimore Washington Intl. Thurgood Marshall) typically departs at approximately 12:55 AM local time. This service is operated by American Airlines and is a seasonal service active in September. An early departure like this can help maximise your time at your destination. To compare early flights on Expedia, select the "Early Morning" and "Morning" filters in your search.
What day of the week has the most flights from Ontario, CA (ONT-Los Angeles - Ontario Intl.) to Baltimore, MD (BWI-Baltimore Washington Intl. Thurgood Marshall)?
If you're flying from Ontario, CA (ONT-Los Angeles - Ontario Intl.) to Baltimore, MD (BWI-Baltimore Washington Intl. Thurgood Marshall), you'll typically find the most flights on a Friday, with around 43 flights available. This gives you plenty of options to choose from. Major airlines on this route include Southwest Airlines, Alaska Airlines, and United Airlines. Flight schedules are fairly consistent throughout the week, so you'll have a good selection of flights no matter which day you choose.
What are the most popular departure times for flights from Ontario, CA (ONT-Los Angeles - Ontario Intl.) to Baltimore, MD (BWI-Baltimore Washington Intl. Thurgood Marshall)?
The most popular departure times for flights from Los Angeles - Ontario Intl. (ONT) to Baltimore Washington Intl. Thurgood Marshall (BWI) are in the early morning, from 6am to 9am. Approximately 27% of passengers prefer this time window. Many major carriers, including Southwest Airlines and United Airlines, offer flights during this window. These times work well because you can get an early start to your travel day and arrive at your destination with plenty of time.
How long does it take to fly from Ontario, CA (ONT-Los Angeles - Ontario Intl.) to Baltimore, MD (BWI-Baltimore Washington Intl. Thurgood Marshall)?
A nonstop flight from ONT to BWI typically takes around 4 hours 50 minutes, covering approximately 2,277 miles. Connecting flights on this route usually add 2 hours 30 minutes to your travel time. Keep in mind that actual flight times can vary due to wind patterns, weather, and air traffic.
Can you fly business or first class from Ontario, CA (ONT-Los Angeles - Ontario Intl.) to Baltimore, MD (BWI-Baltimore Washington Intl. Thurgood Marshall)?
Select the "Business class" and "First class" filters when looking for ONT to 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, CA (ONT-Los Angeles - Ontario Intl.) to Baltimore, MD (BWI-Baltimore Washington Intl. Thurgood Marshall) flight with Expedia?
It's easy to earn miles on a Ontario, CA (ONT-Los Angeles - Ontario Intl.) 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 from Los Angeles - Ontario Intl. (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), San Francisco Intl. (SFO), Sky Harbor Intl. (PHX) 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, CA (ONT-Los Angeles - Ontario Intl.) to Baltimore, MD (BWI-Baltimore Washington Intl. Thurgood Marshall) at the last minute?
Typically, booking a last minute flight from Ontario, CA (ONT-Los Angeles - Ontario Intl.) 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, CA (ONT-Los Angeles - Ontario Intl.) to Baltimore, MD (BWI-Baltimore Washington Intl. Thurgood Marshall) flight and hotel package?
Securing a Ontario, CA (ONT-Los Angeles - Ontario Intl.) 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, CA (ONT-Los Angeles - Ontario Intl.) to Baltimore, MD (BWI-Baltimore Washington Intl. Thurgood Marshall)?
If you booked your Ontario, CA (ONT-Los Angeles - Ontario Intl.) to Baltimore, MD (BWI-Baltimore Washington Intl. Thurgood Marshall) 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
Distance
3643 km
Average flight time
4 hours 45 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 and range up to .  

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 , 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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