ONT - BWI

$100 Find Cheap Flights from Ontario to Baltimore

This is the cheapest one-way flight price found by a KAYAK user in the last 72 hours by searching for a flight from Ontario to Baltimore departing on 3/4. Fares are subject to change and may not be available on all flights or dates of travel. Click the price to replicate the search for this deal.
1 adult
1 adult, Economy, 0 bags

KAYAK searches hundreds of travel sites at once for deals on flights to Baltimore

 
These are the airlines KAYAK users have selected most often from within our search results in flight searches from Ontario to Baltimore.
These are the airlines KAYAK users have selected most often from within our search results in flight searches from Ontario to Baltimore.
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Everything you should know

Cheapest round-trip
$201
Overall average: $512
Frontier
Thu 1/29Mon 2/2
ONT - BWI • 1 stop
Cheapest non-stop
$383
Southwest
Wed 3/11Wed 3/18
ONT - BWI • Non-stop
Our travelers' advice
AI-powered summary based on content written by travel experts. AI can make mistakes.
ONT's streamlined security ensures quick departures.
BWI provides easy access to Baltimore via light rail.
Expert advice
Expert advice
Expert advice
Expert advice
When to book
4 weeks
in advance
Our data shows that travelers who book at least 4 weeks in advance save around 27% compared to booking last minute.
Insights
Insights
Insights
Insights
When to travel
May
Cheapest • 19% price drop
May
Most popular
Good to know
Good to know
+1
+1
Good to know
Good to know
+1
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KAYAK searches 100s of sites at once to find you the best travel deals.
We hope you love your trip to Baltimore!
Flight Deals
Booking Insights
Expert advice
Flight Deals

Cheap Flights from Ontario to Baltimore (ONT-BWI)

 
Here are some of the best deals found on KAYAK recently from the most popular airlines for round-trip flights from Ontario to Baltimore that are departing in the next months. While these flights were available on KAYAK in the last 72 hours, prices and availability are subject to change and deals may expire.
Discover the best prices for you by selecting your travel dates on KAYAK.

Recent round-trip flight deals from Ontario to Baltimore

Thu, Jan 29 - Mon, Feb 2
Frontier Logo
2:06 pm - 10:43 am
ONT
-
BWI
17h 37m1 stop
Frontier Logo
6:00 am - 12:20 am
BWI
-
ONT
21h 20m2 stops
$201Frontier
Thu, Jan 29 - Wed, Feb 4
Frontier Logo
2:06 pm - 10:43 am
ONT
-
BWI
17h 37m1 stop
Frontier Logo
7:10 am - 2:27 pm
BWI
-
ONT
34h 17m2 stops
$218Frontier
Thu, Feb 5 - Wed, Feb 11
Frontier Logo
2:06 pm - 10:43 am
ONT
-
BWI
17h 37m1 stop
Frontier Logo
6:00 am - 9:34 am
BWI
-
ONT
30h 34m2 stops
$223Frontier
Mon, Feb 9 - Fri, Feb 13
Frontier Logo
8:05 pm - 5:13 pm
ONT
-
BWI
18h 08m2 stops
Frontier Logo
7:50 pm - 7:26 am
BWI
-
ONT
14h 36m1 stop
$224Frontier
Tue, Feb 3 - Sun, Feb 8
Multiple Airlines Logo
3:07 pm - 10:31 am
ONT
-
BWI
16h 24m2 stops
Multiple Airlines Logo
7:58 pm - 12:43 pm
BWI
-
ONT
19h 45m1 stop
$235Multiple Airlines
Tue, Feb 3 - Sun, Feb 8
Multiple Airlines Logo
11:53 am - 6:14 pm
ONT
-
BWI
27h 21m1 stop
Multiple Airlines Logo
7:58 pm - 12:43 pm
BWI
-
ONT
19h 45m1 stop
$245Multiple Airlines
Thu, Jan 22 - Sun, Jan 25
Multiple Airlines Logo
2:06 pm - 10:26 am
ONT
-
BWI
17h 20m2 stops
Multiple Airlines Logo
11:43 am - 2:27 pm
BWI
-
ONT
29h 44m1 stop
$252Multiple Airlines
Wed, Feb 11 - Wed, Feb 25
United Airlines Logo
1:24 pm - 11:15 pm
ONT
-
BWI
6h 51m1 stop
United Airlines Logo
4:09 pm - 8:50 pm
BWI
-
ONT
7h 41m1 stop
$257United Airlines
Fri, Feb 20 - Mon, Feb 23
Multiple Airlines Logo
1:18 pm - 10:27 am
ONT
-
BWI
18h 09m1 stop
Multiple Airlines Logo
6:08 pm - 9:34 pm
BWI
-
ONT
30h 26m2 stops
$259Multiple Airlines
Thu, Feb 5 - Thu, Feb 12
Multiple Airlines Logo
4:03 pm - 6:14 pm
ONT
-
BWI
23h 11m1 stop
Multiple Airlines Logo
10:57 am - 12:23 pm
BWI
-
ONT
28h 26m1 stop
$260Multiple Airlines
Booking Insights

KAYAK's insights & trends for Ontario to Baltimore flights

Get data-powered insights and trends into flights from Ontario to Baltimore to help you find the cheapest flights, the best time to fly and much more.

What’s the cheapest day of the week to fly from Ontario to Baltimore?

The average price of all round-trip flights from Ontario to Baltimore clicked on KAYAK for each day over the last 12 months.

Your flight ticket price will generally be cheaper if you fly to Baltimore on a Thursday and more expensive on a Sunday. On your return trip to Ontario, you should consider flying back on a Saturday, and avoid Sundays for better deals.

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

To calculate monthly average prices, KAYAK takes all prices for each month over the last year for round-trip flights from Ontario to Baltimore, removes the top 0.1% to account for outliers, and then takes the median of all values for each month.

The cheapest month for flights from Ontario to Baltimore is May, where tickets cost $361 (return) on average. On the other hand, the most expensive months are January and July, where the average cost of round-trip tickets is $512 and $500 respectively.

Can I save money by flying with a layover from Ontario to Baltimore?

The average round-trip price for all non-stop flights, flights with one layover, and flights with two layovers for the route found by users searching on KAYAK in the last 2 weeks.

Yes, flying with a layover may cost you more time, but you can also save money on the route, with a 1 stop layover the cheapest option at $473 on average.

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

To calculate weekly average prices, KAYAK takes all prices for each week before departure over the last year for round-trip flights from Ontario to Baltimore, removes the top 0.1% to account for outliers, and then takes the average of all the values for each week.

To get a below average price on the flight from Ontario to Baltimore, you should book around 4 weeks before departure, which saves you about 27% compared to booking last minute. For the absolute cheapest price, our data suggests you should book 26 weeks before departure.

Expert advice

Expert advice for your flight from Ontario to Baltimore

 
AI-powered summary based on content written by travel experts. AI can make mistakes.
KAYAK teamed up with top travel experts to share the best tips for your journey.
Airports
ONT

ONT offers streamlined security with average wait times of 6-15 minutes, making it ideal for a stress-free departure.

BWI

BWI offers easy access to downtown Baltimore via light rail, located just outside the terminal.

Our travel experts
Jennifer Simonson

Jennifer Simonson

Expert on ONT

Jennifer Simonson

Jennifer Simonson

Jennifer Simonson is driven by her lifelong commitment to exploring the globe. Her insatiable curiosity had led her to immerse herself into diverse locations like Oklahoma City and Pismo. Her hotel recommendations are the result of the myriad hotels she's stayed at across her travels. Along her journey, she cherishes engaging conversations with locals, indulging in the finest ice cream, trying her hand at surfing, and embarking on nature-filled hikes.

Read more
Harriet Baskas

Harriet Baskas

Expert on BWI

Harriet Baskas

Harriet Baskas

Harriet is an award-winning journalist who is happiest in an airport or an unusual museum. Her stories about airports, air travel, and the business of travel have appeared on NBC News, CNBC, USA TODAY, The Points Guy and other outlets. She is the creator of the StuckatTheAirport.com blog and the author of nine books. When not out on the road or exploring the latest airport amenities, she’s home in Seattle getting ready for the next adventure.

Read more

Good to know

Low seasonJanuary
Cheapest flight$100
Best time to beat the crowds but there is an average 15% increase in price.
Most popular time to fly and prices are also 19% lower on average.
Flight from Ontario to Baltimore

When to book flights from Ontario to Baltimore

Are your dates flexible? Find out the best times to travel from Ontario to Baltimore based on our flight data from the last year. Discover the cheapest month and even day to fly.
Estimated round-trip price
KAYAK looks at all historical flight data for each date to provide a predicted price for one-way trips or round-trips with a duration up to 40 days. While we try to provide actual minimum prices for each date, some prices are predictions and actual prices may differ.

FAQs for booking flights from Ontario to Baltimore

  • What is the cheapest flight from Ontario to Baltimore?

    In the last 3 days, the lowest price for a flight from Ontario to Baltimore was $100 for a one-way ticket and $201 for a round-trip.

  • Do I need a passport to fly between Ontario and Baltimore?

    No, a passport isn't needed to fly from Ontario to Baltimore. However, local authorities might ask for an official ID.

  • Which airports will I be using when flying from Ontario to Baltimore?

    Ontario airport is called Ontario and the only airport in Baltimore is Baltimore/Washington.

  • Which airlines offer Wi-Fi service onboard planes from Ontario to Baltimore?

    JetBlue, Delta, Hawaiian Airlines, American Airlines, and Alaska Airlines offer inflight Wi-Fi service on the Ontario to Baltimore flight route.

  • Which aircraft models fly most regularly from Ontario to Baltimore?

    The Boeing 737 MAX 8 is the aircraft model that flies most regularly on the Ontario to Baltimore flight route.

  • Which airline alliances offer flights from Ontario to Baltimore?

    SkyTeam, Star Alliance, and oneworld are the airline alliances operating flights between Ontario and Baltimore, with SkyTeam being the most commonly used for this route.

  • Which is the best airline for flights from Ontario to Baltimore, Southwest or Delta?

    The two airlines most popular with KAYAK users for flights from Ontario to Baltimore are Southwest and Delta. With an average price for the route of $469 and an overall rating of 8.0, Southwest is the most popular choice. Delta is also a great choice for the route, with an average price of $427 and an overall rating of 7.9.

  • How does KAYAK find such low prices on flights from Ontario to Baltimore?

    KAYAK is a travel search engine. That means we look across the web to find the best prices we can find for our users. With over 2 billion flight queries processed yearly, we are able to display a variety of prices and options on flights from Ontario to Baltimore.

  • How does KAYAK's flight Price Forecast tool help me choose the right time to buy my flight ticket from Ontario to Baltimore?

    KAYAK’s flight Price Forecast tool uses historical data to determine whether the price for a flight to Baltimore from Ontario is likely to change within 7 days, so travelers know whether to wait or book now.

  • What is the Hacker Fare option on flights from Ontario to Baltimore?

    Hacker Fares allow you to combine one-way tickets in order to save you money over a traditional round-trip ticket. You could then fly to Baltimore with an airline and back to Ontario with another airline. Booking your flights between Ontario and BWI can sometimes prove cheaper using this method.

  • What is KAYAK's "flexible dates" feature and why should I care when looking for a flight from Ontario to Baltimore?

    Sometimes travel dates aren't set in stone. If your preferred travel dates have some wiggle room, flexible dates will show you all the options when flying to Baltimore from Ontario up to 3 days before/after your preferred dates. You can then pick the flights that suit you best.

KAYAK’s top tips for finding a cheap flight from Ontario to Baltimore

  • Looking for a cheap flight? 25% of our users found flights on this route for $238 or less one-way and $406 or less round-trip.

Prefer to fly direct from Ontario to Baltimore?

 
Direct data is based off flight results for the next 60 days. Find direct flights from all airlines flying direct from Ontario to Baltimore/Washington.
Find which airlines fly direct from Ontario Airport to Baltimore/Washington Airport, which days they fly and book direct flights.

Direct departures

Ontario to Baltimore/Washington

Monday

Southwest

Southwest

Tuesday

Southwest

Southwest

Wednesday

Southwest

Southwest

Thursday

Southwest

Southwest

Friday

Southwest

Southwest

Saturday

Southwest

Southwest

Sunday

Southwest

Southwest

See more direct flights

Direct returns

Baltimore/Washington to Ontario

Monday

Southwest

Southwest

Tuesday

Southwest

Southwest

Wednesday

Southwest

Southwest

Thursday

Southwest

Southwest

Friday

Southwest

Southwest

Saturday

Southwest

Southwest

Sunday

Southwest

Southwest

See more direct flights

Reviews of the top 5 airlines serving from Ontario to Baltimore

 
See real verified KAYAK customer reviews for airlines flying from Ontario to Baltimore. Airline scores are aggregated from all reviews left by passengers on KAYAK after flying with an airline. KAYAK doesn’t show reviews that are older than 5 years. Learn how KAYAK collects reviews.
Need help choosing which airline to fly with from Ontario to Baltimore? KAYAK airline reviews give an overall score for each airline based on loads of factors, including comfort, boarding, in-flight entertainment and more, to make your decision easier. See airline scores according to verified KAYAK customer reviews.
8.0
SouthwestOverall score based on 4250 reviews
8.6Crew
7.5Entertainment
8.1Boarding
7.0Food
8.0Comfort
Airline reviews

Never went on board this flight. Kayak uses Underpricer (which is a scam business) as it's "customer service provider". This customer service is a classic bait and switch "service". I Got caught in the UnderPricer Bait and switch scam. 14 hours on the phone with people from India with heavy accents and upselling me to useless products. The original sell was a flight on spirit. Then they contact me later, an say after they have my money that the flight is no good as is is only one seat for a party of two. I am still in dispute to get my money back. Went to Spirit direct and had a beautiful vacation. I should never have used Kayak and their rip off artists UnderPricer.

2.0 MediocreAnonymous, Jan 2026
SJU - BWI
Read more Southwest reviews

Never went on board this flight. Kayak uses Underpricer (which is a scam business) as it's "customer service provider". This customer service is a classic bait and switch "service". I Got caught in the UnderPricer Bait and switch scam. 14 hours on the phone with people from India with heavy accents and upselling me to useless products. The original sell was a flight on spirit. Then they contact me later, an say after they have my money that the flight is no good as is is only one seat for a party of two. I am still in dispute to get my money back. Went to Spirit direct and had a beautiful vacation. I should never have used Kayak and their rip off artists UnderPricer.

The boarding and seat assignment system no longer works for me, but I know it is being replaced. Otherwise, I am good with the overall experience.

The lead steward kept singing about "San Francisco" and hotel California---more annoying than humorous....needs work. Flight was smooth and on time.

San Diego airport is brand new, spacious, airy and very smooth checkin at SW baggage drop.

Crew could have been friendlier, maybe I'm spoiled by SW crews. In flight wifi was good. Would be nice to have more food offerings on a 4 plus hour flight

Ever since Southwest starting charging for bags, passengers don't want to pay to check their bags, so the gate agents have to beg people to check their roller bags now because there's "not enough space". This was a terrible business move by Southwest.

All was good. I just had a hard time getting connected to the WiFi/internet during the flight

Sacrament staff are always polite and helpful. Airport is easy to maneuver and boarding is straightforward.

Great flight. Outstanding Service. Southwest was able to put us on a direct flight to Denver when the connection could have been affected by a later arrival to Baltimore. The direct flight was less expensive that the flight with the connection in Baltimore.

As always, the entire Southwest experience was wonderful, from online booking to flight to baggage retrieval. Very grateful.

DTW line is too long. The flights from DTW to BWI are always delayed for unknown reasons.

The flight was delayed for about 2 hrs. Other than it, it was good.

I am extremely disappointed that delta internal pilot manuals now refer to the Gulf of Mexico as the “gulf of America”. You can bow down to the Orange turd on your own. I will never fly delta again

No lunch on a x-country flight scheduled for 10:50 am departure, arrived 5+ hrs later. That requires a black box label before you pay for the tickets. Worst, when I checked in online, it's specifically said that lunch was served on his flight for economy Plus passengers.

Our flight from SFO to MSP was right on time on 11/15/2025. No delays. As we approached MSP at about 8 pm, we circled in the air until 8:40 pm so I don't call that efficient for MSP. I think the captain should announce the delay and why. (as if we all don't know that we are just circling around the area, slowing down, speeding up, slowing down.) Thank you. Marilyn Fischer

Staff were friendly and happy. Delta could make sure passengers that don't have the app know of changes. Without Kayak I would not have known about the change of gate or the delay. Kayak was faster to notify me.

The flight used a B767 with a very old interior from before 2014. The entertainment system did not work at all during the flight despite attempts to reset the system. It was like they flew this route just to be competitive.

Delayed flight (1hour) plus a long layover after an overnight flight with no backup plane available.

Flight delayed for two and half hours and then canceled altogether due to mechanical issues. No mechanic onsite to fix so had to send one from LAX.

My husband upgraded our seats and I don't know if it was due to the type of planet was or if they didn't upgrade our seats. We were supposed to be in I believe comfort seats and they were just as tight as any other seat- no leg room and we are very tall people but at least it wasn't extremely cold. My husband did put in a complaint about our seating because he paid extra and if we would have known that the space and the tightness would have been the same, we just would have gotten the emergency row emergency row seats that we normally get. We love Delta but both our flights coming home we're not good. Oh I forgot to mention that on our flight to Hawaii our luggage wheels got broke and we had to purse new luggage on vacation then we never had this problem so we didn't know protocol and reported it after we got home only for them to tell is we only had 24hrs to report the damage. Not sure what was going on with Delta this vacation trip.

I’m so sorry, I can’t remember her name, I believe it was Dimpti. She was stellar, also a mature Asian flight attendant, lots of flowers in her hair, just as amazing! But literally the crew was AWESOME . Only downside is there weren’t any charging outlets. Maybe I needed to ask a flight attendant , but it would’ve been nice to have one easily accessible.

I boarded flight UA#1318 at Sacramento International Airport going back to Houston TX. The flight was scheduled at 5:10am. I was able to check in virtually using the United Airlines app. When I entered the airport, there was no one outside assisting with checked bags as it was for Delta Airlines. Immediately upon entering, there was a LONG, EXTREMELY LONG line to the kiosks to get boarding passes. I stand in line to get boarding passes then had to move to ANOTHER EXTREMELY LONG line to get my bags checked in. While standing in this line, we noticed an agent taking customers to 3 at a time to her station to check their bags in. Lucky for me, she called me back, checked my bags for me and I was on my way. I then encountered another long line at the TSA check and to avoid I ending up having to sign up for CLEAR to bypass it. So glad, I did.,...Both of my flights were great with no issues, butthe check in progress at Bush Airport was so much smoother. Check-in at SMF airport needs to be anaylzed and corrected. Do better United, I know you can....thanks

Pushed back only to get deplaned due to a tire damaged by ground crew. They did at least go pretty fast. The bathrooms should be banned under the Geneva convention. No room to even sit straight on the toilet. The under-seat entertainment units block what little leg room there is.

United airlines has the best customer experience from booking to arrival. I always fly United airlines. The mileage program is excellent

Older aircraft, no meal, only food was for purchase. Not impressed United.

Not pleasant trip cross country when the entertainment and WiFi system not working. No entertainment for entirety of route. Staff was rather nonchalant in that they dismissed the problem due to age of plane. It would have been nice to know this up front so I could have come prepared to read or download movies before boarding Coincidentally or not, there was a similar issue with the entertainment system on my previous flight I took on my fist leg of the trip. There are no seat TVs, so you must rely on the app when it works. United can do better. Also, what use it it to pay for boarding group 2 when half of the passengers are in the same line as you?

Premium Plus is a really good idea for longer flights

The flight attendants were great, I joked with one I can’t remember her name, a blond, really sweet. I thought it was run well very professional. This was great i survived Spirit, I know for which I speak.

I was in first class. The outlets at my seat did not work. The plane was shabby and run down. I had prepurchsed a day subscription for internet that was not redeemable. I had to repurchase the internet for my flight and then it didn’t work anyway. Quite disappointed in what was supposed to be the launch of a great vacation.

I understand stuff happens, but plane failures are likely due to lack of maintenance. Additionally, air conditioning wasn't working, no snack/drink service, no WiFi. Fortunately, the crew was communicative and light-hearted. United grabbed another plane and we were able to get to our destination.

The flight was on time and arrived early. The crew were friendly and helpful.

Overall experience was great. Flights were almost on time in departing and we arrived at our destination as scheduled. No issues with amenities or flight crew. Everything went well as as expected. Will fly again with American Airlines in the future!

I like that the crew kept us informed but we moved back and forth from gate to gate before the aircraft arrived.

Horrible. Both legs of my flight were delayed more than 6 hours. No compensation, no screens on the plane, and the plane was not clean.

The flight was smooth, the pilot kept us informed about delays and we arrived more of less on time

The flight was flawless and we even arrived between 20 and 25 minutes early!

Always seated jammed in rear of aircraft Admirals Club food at DFW terminal D was absolute worst food experience and I pay $600/year to eat this dried out junk

Mostly good. Flight was crowded but Airline personnel were very friendly & accommodating. It would be good to have savory snacks rather than just sweet Biscoff cookies.

It was a red eye flight, so no meals were provided, but it was fine with snacks. The seats felt cramped and almost too narrow.

Very crowded flight but what can you expect these days?? Crew was accommodating.

It was ok. It was expensive to check 2 bags ($75.00 per bag), and then it took a long time to wait for shuttle to take us from one terminal to the terminal where the plane was taking off at LAX. And all of this for a flight where we had to pay for any food or drink that was not water.

When I wanted to check in 3 hours prior to boarding time, the employees mentioned “a little over an hour delay” so I waited for an hour then I went to go look for food in the terminal and most people from that flight were in the same area looking for food. Finally I decided after food to check to see if it’s anytime closer and now it’s 2 mins until boarding closes?! What are you kidding me? I didn’t receive anything via sms about boarding now nor via email or on the intercom. I luckily made it through, barely, and then there’s no room for my carry on mind you I’m in the very first row so I had to place my purse in one further row back and my carry on sections down. Not sure who pays for better seats to get your stuff placed all over the plane but that was the worst experience I’ve ever had flying with anyone.

Inbound plane was on time and flight departed on time with no issues while boarding.

This airline sucks. They offer low rates then charge you for everything, the app does not work well, the seats are the most uncomfortable. Maintenance issues on the flight, and you still have to sit through their credit card commercials. People are nice enough but does not make up for overall poor experience.

After boarding and un-boarding twice over 6+hours, the flight was canceled.

Cancelled flight after I arrived at airport after 75 min drive and parking. Next flight was 4 days in the future. Had to scramble and buy a much more expensive flight on another carrier.

The Boarding process in Denver was chaotic, and since the line was so long, we were lined up very far from the gate. If there were any announcements from the gate staff, we didn't hear them. The flight attendants were spectacular. The only negative part of the flight was sitting by a 2 1/2 year old who was unruly and unfortunately had parents that matched his behaviors. Also, the restaurants in Denver on the E concourse, they didn't have food (passengers could only order 1 item on the entire menu) or the restaurants had 12-14 people waiting for orders to be prepared and another 6 people waiting to order. If you have a layover in Denver and need to grab food, be prepared to visit the shops with pre-packaged sandwiches, or you can visit another concourse but it may take a while to transit throughout the airport.

I liked the turn-style feature at gate 209B at LAX. Very efficient process. The gate staff also made several, clearly directed announcements so I felt very informed.

The seats were awful, hard plastic covered in sheet vinyl. The airline tries to scam you into paying extra to get seat together when the flight wasn’t full. They were going to separate a family with young children but my wife who had a row to herself gave up her seat so the young mom could be with her young boys. I’m never giving this airline my money again.

It was a short flight so no food or entertainment….

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

Information on your arrival and departure airports