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$66+ Cheap flights from Ontario to Baltimore (ONT - BWI)

This is the cheapest one-way flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 1/22. Fares are subject to change and may not be available on all flights or dates of travel.
ONT — BWI
Nov 21 — Nov 281
Fri 11/21
Fri 11/28
1 adult, Economy
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Cheapflights Tip: The best prices from Ontario to Baltimore/Washington are usually found in May or September, booked 70 days in advance, depart on a Thursday or Tuesday and return on a Friday

Find flight deals from Ontario to Baltimore

Cheapest flights from Ontario to Baltimore
Explore the most affordable flight options available from Ontario to Baltimore. Find the lowest fares from popular airlines and budget airlines, with prices last updated on October 22, 2025.

This American Airlines deal was found by Cheapflights users on 10/20. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 12/410:34 pmONT - BWI
1 stop8h 40mAmerican Airlines
Tue 12/96:00 amBWI - ONT
2 stops13h 02mAmerican Airlines
Deal found 10/20$154
This Kiwi.com deal was found by Cheapflights users on 10/20. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 12/52:05 pmONT - BWI
1 stop16h 12mMultiple Airlines
Mon 12/88:39 pmBWI - ONT
1 stop17h 48mMultiple Airlines
Deal found 10/20$176
This Kiwi.com deal was found by Cheapflights users on 10/20. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 12/36:15 amONT - BWI
2 stops14h 01mMultiple Airlines
Mon 12/88:39 pmBWI - ONT
1 stop17h 48mMultiple Airlines
Deal found 10/20$178
This Kiwi.com deal was found by Cheapflights users on 10/20. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 12/52:05 pmONT - BWI
1 stop16h 12mMultiple Airlines
Sun 12/711:14 amBWI - ONT
1 stop32h 09mMultiple Airlines
Deal found 10/20$185
This Kiwi.com deal was found by Cheapflights users on 10/20. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 11/86:53 amONT - BWI
2 stops10h 38mMultiple Airlines
Wed 11/126:24 pmBWI - ONT
1 stop27h 25mMultiple Airlines
Deal found 10/20$186
This Kiwi.com deal was found by Cheapflights users on 10/20. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 12/36:15 amONT - BWI
2 stops14h 01mMultiple Airlines
Sun 12/711:14 amBWI - ONT
1 stop32h 09mMultiple Airlines
Deal found 10/20$187
This Kiwi.com deal was found by Cheapflights users on 10/20. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 12/52:05 pmONT - BWI
1 stop16h 12mMultiple Airlines
Wed 12/108:00 amBWI - ONT
2 stops37h 35mMultiple Airlines
Deal found 10/20$190
This Kiwi.com deal was found by Cheapflights users on 10/20. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 12/42:59 pmONT - BWI
2 stops27h 38mFrontier
Mon 12/88:39 pmBWI - ONT
1 stop17h 48mFrontier
Deal found 10/20$191
This Kiwi.com deal was found by Cheapflights users on 10/19. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 11/118:45 amONT - BWI
2 stops30h 44mFrontier
Sat 11/153:05 pmBWI - ONT
1 stop18h 22mFrontier
Deal found 10/19$193
This Kiwi.com deal was found by Cheapflights users on 10/20. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 11/131:46 pmONT - BWI
1 stop17h 38mMultiple Airlines
Sun 11/166:24 pmBWI - ONT
1 stop27h 25mMultiple Airlines
Deal found 10/20$194
This Kiwi.com deal was found by Cheapflights users on 10/20. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 12/52:05 pmONT - BWI
1 stop16h 12mMultiple Airlines
Tue 12/98:00 amBWI - ONT
2 stops16h 17mMultiple Airlines
Deal found 10/20$197

Cheap flight deals from Ontario to Baltimore

Discover tips and strategies to find the most affordable flight options for your journey from Ontario (ONT) to Baltimore (BWI). Learn about various techniques such as flexible date searches, comparing prices across and setting up price alerts. Use these methods to find the cheapest flights available for your travel needs. Data last updated October 22, 2025.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$154
(American Airlines)

One-way from

$66
(Kiwi.com)

Popular in

November

Cheapest in

May

Average price

$461
Provider with most accurate pricing for Ontario-Baltimore/Washington flight deals.
Search Deals
Provider most trusted by Cheapflights users for Ontario-Baltimore/Washington flights.
Search Deals
From Ontario to Baltimore/Washington
Search Deals
One-way flight from Ontario to Baltimore/Washington
Search Deals
Highest demand for flights based on searches. 4% potential increase in price ($24 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 1% potential price decrease ($6 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in October 2025
Search Deals

Cheapflights Fare Finder

 
Customize your flight search to find flights from Ontario to Baltimore that fit within your specific budget. Explore options based on user searches and filter the results based on your desired price range. Find flights that match your budget for a cost-effective journey. Over the last 7 days, Cheapflights users made 2,558,603 searches. Data last updated October 22, 2025.
Use the filters below to find and compare flights from Ontario to Baltimore that are best for you.

Fly from

Ontario

Fly to

Baltimore

Route

Depart

Return

Price

OntarioBaltimore

ONT - BWI

ONTBWI

Ontario

Fri 12/5

10:25 pm-10:05 am

1 stop8h 40m

Baltimore/Washington

Wed 12/10

1:52 pm-7:39 pm

1 stop8h 47m

$257

OntarioBaltimore

ONT - BWI

ONTBWI

Ontario

Mon 12/8

12:40 pm-6:00 am

2 stops14h 20m

Baltimore/Washington

Tue 12/16

6:00 am-5:07 pm

2 stops14h 07m

$316

OntarioBaltimore

ONT - BWI

ONTBWI

Ontario

Thu 12/25

7:05 am-5:51 pm

1 stop7h 46m

Baltimore/Washington

Wed 1/7

7:00 am-11:38 am

1 stop7h 38m

$327

OntarioBaltimore

ONT - BWI

ONTBWI

Ontario

Sun 1/18

1:00 pm-12:11 am

1 stop8h 11m

Baltimore/Washington

Fri 1/23

7:00 am-11:38 am

1 stop7h 38m

$327

OntarioBaltimore

ONT - BWI

ONTBWI

Ontario

Sun 3/1

10:30 pm-9:15 am

1 stop7h 45m

Baltimore/Washington

Tue 3/3

4:39 pm-9:14 pm

1 stop7h 35m

$329

OntarioBaltimore

ONT - BWI

ONTBWI

Ontario

Sat 11/15

5:49 pm-10:43 am

2 stops13h 54m

Baltimore/Washington

Wed 11/19

4:49 pm-11:04 pm

1 stop9h 15m

$341

OntarioBaltimore

ONT - BWI

ONTBWI

Ontario

Wed 12/3

1:34 pm-11:00 pm

1 stop6h 26m

Baltimore/Washington

Tue 12/9

4:15 pm-8:42 pm

1 stop7h 27m

$343

OntarioBaltimore

ONT - BWI

ONTBWI

Ontario

Tue 11/11

5:49 pm-10:43 am

2 stops13h 54m

Baltimore/Washington

Sat 11/15

7:15 am-5:09 pm

2 stops12h 54m

$345

OntarioBaltimore

ONT - BWI

ONTBWI

Ontario

Sat 11/15

12:16 pm-12:26 am

1 stop9h 10m

Baltimore/Washington

Sun 11/16

7:15 am-12:18 pm

1 stop8h 03m

$367

OntarioBaltimore

ONT - BWI

ONTBWI

Ontario

Wed 11/19

8:00 am-11:16 pm

2 stops36h 16m

$97

Flights are sorted by cheapest round-trip flights first.

Deals found on 10/21

Showing 1-10 of 21 results
1
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Compare providers for flights from Ontario to Baltimore

Provider information is updated monthly. Please note that these providers often have deals for this flight, but the availability may vary on a day-by-day basis on Cheapflights.
Use the table below to compare price accuracy, trust ratings, and cancellation policies for each provider offering flight deals from Ontario to Baltimore in October.
ProviderPrice AccuracyTrust Score*
ExpediaPrice Accuracy2 starsTrust Score*3 stars
FlightHubPrice Accuracy3 starsTrust Score*3 stars
eDreamsPrice Accuracy3 starsTrust Score*3 stars
CheapflightsfaresPrice Accuracy2 starsTrust Score*1 star
PricelinePrice Accuracy1 starTrust Score*3 stars

*The Trust Score is based on feedback from users after their booking experience. It measures overall satisfaction, helping us identify issues like hidden fees, problems during the ticketing process, and the quality of customer service. This score is our best indicator of the provider's quality and reliability.

  • Most accurate provider: When it comes to deals on Ontario-Baltimore flights, users find the pricing of FlightHub to be most consistent on Cheapflights vs. FlightHub Users can find the same prices on Ontario-Baltimore flight deals on Cheapflights vs. FlightHub >95% of the time. Price accuracy is based on data collected from Ontario-Baltimore flight searches over the past month and is updated monthly.
  • Most trusted provider: When it comes to deals on Ontario-Baltimore flights, Cheapflights users trust FlightHub the most. FlightHub has received a user feedback score of 3 out of 3 stars (3 being the best), meaning they have been trusted the most by Cheapflights users looking for Ontario-Baltimore flight deals. Provider user feedback score is based on Cheapflights searches over the past month and is updated monthly.

Best time to book a flight from Ontario to Baltimore

Have a flexible travel schedule? Discover the best time to fly to Baltimore from Ontario with our price prediction graph.
Estimated round-trip price
Rates are based on past data. Find the cheapest month and day to book your flight based on your travel requirements, then search for cheap deals.

Cheapflights Insights

Everything you need to know about your flight from Ontario to Baltimore

How far ahead should I book a flight from Ontario to Baltimore?

Use this chart to determine the optimal time to book a round-trip flight from Ontario to Baltimore. Price data was last updated on October 17, 2025.

The best time to book flights from Ontario to Baltimore is 70 days before your desired departure date. The cost of your flight will likely increase significantly if you book two weeks in advance of your flight.

What is the cheapest month to book a flight from Ontario to Baltimore?

Currently, August is the cheapest month in which you can book a flight from Ontario to Baltimore (average of $93). Flying from Ontario to Baltimore in December is currently the most expensive (average of $165). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

What is the cheapest time of day to fly from ONT to BWI?

Find hourly flight availability from Ontario to Baltimore. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated October 22, 2025.

One of the essential ways to save on airfare from Ontario to Baltimore is to remain as flexible as possible. Flights that are in the afternoon tend to be the most expensive. A flight in the morning could potentially save you up to 16% on airfare.

What is the cheapest day to fly from Ontario to Baltimore?

Use this chart to determine the cheapest time to fly round-trip from Ontario to Baltimore. Price data was last updated on October 19, 2025.

Travelers seeking maximum savings on their Ontario to Baltimore flight should consider departing on Tuesday afternoons when fares are most often at their lowest. Thursday afternoons flights should be avoided if possible as fares are typically the most expensive at this time.

Reviews of airlines servicing Baltimore

Get insights into the airlines that provide service to Baltimore. Read reviews, discover amenities, and learn about the overall travel experience offered by airlines. Use this information to make informed decisions when choosing an airline for your flight to Baltimore. Reviews last updated October 22, 2025.
Read reviews from past customers who have flown Southwest, Delta, and United Airlines from Ontario to Baltimore. Users can see the overall rating for each airline as well as how each is rated in terms of entertainment options, comfort, food, crew/service, and boarding process.
Southwest
8.0
Very good
4,237 reviews

Boarding

8.1

Crew

8.6

Entertainment

7.5

Overall

8.0

Comfort

8.0

Food

7.0

Reviews

1 / 20
8.0
Excellent

Walter,Aug 2025

OAK - SAN

Dozens of flights and I've never seen a row's beverages forgotten. I even went back and asked the attendant to check on them and nothing. I really hope it didn't have something to do with the Black mother with her kid in the row. Otherwise it was a typical Southwest flight, rapid boarding, tolerable leg room.
Southwest
8.0
Very good
4,237 reviews
Southwest
8.0
Very good
4,237 reviews

Boarding

8.1

Crew

8.6

Entertainment

7.5

Overall

8.0

Comfort

8.0

Food

7.0

Reviews

1 / 20
8.0
Excellent

Walter,Aug 2025

OAK - SAN

Dozens of flights and I've never seen a row's beverages forgotten. I even went back and asked the attendant to check on them and nothing. I really hope it didn't have something to do with the Black mother with her kid in the row. Otherwise it was a typical Southwest flight, rapid boarding, tolerable leg room.
Delta
7.9
Good
7,981 reviews
Southwest
8.0
Very good
4,237 reviews

Boarding

8.1

Crew

8.6

Entertainment

7.5

Overall

8.0

Comfort

8.0

Food

7.0

Reviews

1 / 20
8.0
Excellent

Walter,Aug 2025

OAK - SAN

Dozens of flights and I've never seen a row's beverages forgotten. I even went back and asked the attendant to check on them and nothing. I really hope it didn't have something to do with the Black mother with her kid in the row. Otherwise it was a typical Southwest flight, rapid boarding, tolerable leg room.
United Airlines
7.4
Good
8,990 reviews
Southwest
8.0
Very good
4,237 reviews

Boarding

8.1

Crew

8.6

Entertainment

7.5

Overall

8.0

Comfort

8.0

Food

7.0

Reviews

1 / 20
8.0
Excellent

Walter,Aug 2025

OAK - SAN

Dozens of flights and I've never seen a row's beverages forgotten. I even went back and asked the attendant to check on them and nothing. I really hope it didn't have something to do with the Black mother with her kid in the row. Otherwise it was a typical Southwest flight, rapid boarding, tolerable leg room.
American Airlines
7.2
Good
11,028 reviews
Southwest
8.0
Very good
4,237 reviews

Boarding

8.1

Crew

8.6

Entertainment

7.5

Overall

8.0

Comfort

8.0

Food

7.0

Reviews

1 / 20
8.0
Excellent

Walter,Aug 2025

OAK - SAN

Dozens of flights and I've never seen a row's beverages forgotten. I even went back and asked the attendant to check on them and nothing. I really hope it didn't have something to do with the Black mother with her kid in the row. Otherwise it was a typical Southwest flight, rapid boarding, tolerable leg room.
Frontier
5.8
Fair
3,129 reviews
Southwest
8.0
Very good
4,237 reviews

Boarding

8.1

Crew

8.6

Entertainment

7.5

Overall

8.0

Comfort

8.0

Food

7.0

Reviews

1 / 20
8.0
Excellent

Walter,Aug 2025

OAK - SAN

Dozens of flights and I've never seen a row's beverages forgotten. I even went back and asked the attendant to check on them and nothing. I really hope it didn't have something to do with the Black mother with her kid in the row. Otherwise it was a typical Southwest flight, rapid boarding, tolerable leg room.

Related info for your journey

Find useful and relevant information for your journey from Ontario to Baltimore. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.

  • How popular is this Ontario to Baltimore flight route?

    This flight path from Ontario to Baltimore/Washington was viewed by 7 users in the past month. Keep an eye out for changes in search interest prior to high and low season.

  • How long is the flight from Ontario to Baltimore?

    Airlines like Delta fly from Ontario to Baltimore in about 8h 40m. The time it takes to get you to your destination can typically vary by up to . The distance from Ontario to Baltimore is about 2276 mi.

  • What are the cheapest airlines flying from Ontario to Baltimore round-trip?

    Our cheapest airline available from Ontario to Baltimore is Spirit Airlines. Our recent data shows that you can find tickets from as low as $98 on this airline. Additional options worth looking into are Frontier and United Airlines, starting at $175 and $256 round-trip. These flights start at 78% lower than the current average price 3 months from now.

  • What are the cheapest flights from Ontario to Baltimore?

    Looking for the cheapest flight from Ontario to Baltimore? While on average our users pay $357, our data indicates the cheapest price to be $159. The most popular route (Ontario - Baltimore/Washington), is priced around $257.

  • Can I find deals for flights from Ontario to Baltimore that include hotel bookings?

    Yes. In addition to deals on Ontario to Baltimore flights, Cheapflights offers vacation packages that include both flights and hotel.

  • How can I find direct flights from Ontario to Baltimore?

    After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from Ontario to Baltimore.

  • Can I find deals for business class flights from Ontario to Baltimore?

    Yes. Cheapflights offers flight deals from Ontario to Baltimore by cabin class. In addition to browsing deals, you can also filter by cabin class on the search results page after making a search.

  • What is the cheapest month to book a flight from Ontario to Baltimore?

    Currently, August is the cheapest month in which you can book a flight from Ontario to Baltimore (average of $93). Flying from Ontario to Baltimore in December is currently the most expensive (average of $165). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

See more FAQs

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Top 6 airlines flying from Ontario to Baltimore

Discover the top 6 airlines that operate flights from Ontario to Baltimore. Compare their services, reliability, and customer satisfaction ratings to choose the airline that best suits your travel preferences and needs. Over the last 7 days, Cheapflights users made 2,558,603 searches. Data last updated October 22, 2025.
AirlineCheapestAverageFlexibilityOn-time
Spirit AirlinesCheapest$98Average$212FlexibilityNo cancel feeOn-time65%
FrontierCheapest$175Average$240FlexibilityNo cancel feeOn-time62%
United AirlinesCheapest$256Average$438FlexibilityNo cancel feeOn-time69%
DeltaCheapest$326Average$446FlexibilityNo cancel feeOn-timeN/A
SouthwestCheapest$337Average$472FlexibilityNo cancel feeOn-time63%
American AirlinesCheapest$346Average$544FlexibilityNo cancel feeOn-time71%

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