STL - BWI

$70 Find Cheap Flights from St. Louis 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 St. Louis to Baltimore departing on 8/4. 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 St. Louis to Baltimore, as well as popular online travel agencies
These are the airlines KAYAK users have selected most often from within our search results in flight searches from St. Louis to Baltimore, as well as popular online travel agencies
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Everything you should know

Cheapest round-trip
$138
Typical prices: $470-$239
Frontier
Tue 8/4Wed 8/12
STL - BWI • 1 stop
Cheapest non-stop
$251
Typical prices: $529-$301
Southwest
Tue 8/4Wed 8/12
STL - BWI • Non-stop
Nonstop flights
You can fly direct with Southwest. Average duration is 2h 03m
Direct flights
Direct flights
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Direct flights
Direct flights
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Top layover airports
Cheapest • Avg $224 (round-trip)
Shortest trip • 4h 27m (one-way)
Insights
Insights
Insights
Insights
When to book
in advance
Our data shows that travelers who book at least 4 weeks in advance save around 30% compared to booking last minute.
Insights
Insights
Insights
Insights
When to travel
Cheapest • 29% price drop
Most popular
Good to know
Good to know
+1
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Good to know
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Flight Deals
Booking Insights
Expert advice
Flight Deals

Cheap Flights from St. Louis to Baltimore (STL-BWI)

 
Here are some of the best deals found on KAYAK recently from the most popular airlines for round-trip flights from St. Louis 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 St. Louis to Baltimore

Tue, Aug 4 - Wed, Aug 12
Frontier Logo
6:34 pm - 7:26 am
STL
-
BWI
11h 52m
1 stop
Frontier Logo
9:37 pm - 5:37 pm
BWI
-
STL
21h 00m
1 stop
$138Frontier
Tue, Jul 14 - Tue, Jul 21
Frontier Logo
6:34 pm - 7:26 am
STL
-
BWI
11h 52m
1 stop
Frontier Logo
6:35 am - 5:37 pm
BWI
-
STL
12h 02m
1 stop
$144Frontier
Tue, Sep 22 - Tue, Sep 29
Frontier Logo
10:35 am - 6:36 pm
STL
-
BWI
7h 01m
1 stop
Frontier Logo
7:31 pm - 9:40 am
BWI
-
STL
15h 09m
1 stop
$145Frontier
Mon, Aug 17 - Wed, Aug 19
Frontier Logo
4:57 pm - 7:45 am
STL
-
BWI
13h 48m
1 stop
Frontier Logo
9:32 pm - 5:30 pm
BWI
-
STL
20h 58m
1 stop
$147Frontier
Fri, Jul 3 - Tue, Aug 11
Frontier Logo
5:06 pm - 4:26 pm
STL
-
BWI
22h 20m
1 stop
Frontier Logo
8:25 am - 5:37 pm
BWI
-
STL
10h 12m
1 stop
$153Frontier
Tue, Sep 22 - Wed, Sep 30
Frontier Logo
10:35 am - 6:36 pm
STL
-
BWI
7h 01m
1 stop
Frontier Logo
9:20 pm - 9:40 am
BWI
-
STL
13h 20m
1 stop
$157Frontier
Fri, Jul 3 - Wed, Aug 12
Frontier Logo
5:06 pm - 4:26 pm
STL
-
BWI
22h 20m
1 stop
Frontier Logo
9:37 pm - 5:37 pm
BWI
-
STL
21h 00m
1 stop
$158Frontier
Sat, Aug 8 - Tue, Aug 11
Frontier Logo
4:57 pm - 11:17 pm
STL
-
BWI
5h 20m
1 stop
Frontier Logo
8:25 am - 5:37 pm
BWI
-
STL
10h 12m
1 stop
$159Frontier
Fri, Aug 7 - Tue, Aug 11
Frontier Logo
4:57 pm - 7:26 am
STL
-
BWI
13h 29m
1 stop
Frontier Logo
8:25 am - 5:37 pm
BWI
-
STL
10h 12m
1 stop
$162Frontier
Mon, Aug 3 - Thu, Aug 6
Frontier Logo
4:57 pm - 7:26 am
STL
-
BWI
13h 29m
1 stop
Frontier Logo
6:35 am - 5:37 pm
BWI
-
STL
12h 02m
1 stop
$163Frontier
Booking Insights

KAYAK's insights & trends for St. Louis to Baltimore flights

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

How much is a round-trip flight from St. Louis to Baltimore?

This analysis is based on the cheapest round-trip price found on KAYAK in the last 12 months by searching for a flight from St. Louis to Baltimore departing in August.

What’s the cheapest day of the week to fly from St. Louis to Baltimore?

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

When flying from St. Louis to Baltimore, you should consider leaving on a Tuesday and avoid Mondays if you are looking for the best rates. For your return to St. Louis, you’ll find the best rates on Wednesdays and the most expensive ones on Mondays.

What is the cheapest month to fly from St. Louis to Baltimore?

To calculate monthly average prices, KAYAK takes all prices for each month over the last year for round-trip flights from St. Louis 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 St. Louis to Baltimore is September, where tickets cost $284 (return) on average. On the other hand, the most expensive months are February and June, where the average cost of round-trip tickets is $493 and $491 respectively.

Can I save money by flying with a layover from St. Louis 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.

No, with an average price for the route of $445, prices are generally cheapest when you fly direct.

How far in advance should I book a flight from St. Louis 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 St. Louis 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 St. Louis to Baltimore, you should book around 4 weeks before departure, which saves you about 30% compared to booking last minute. For the absolute cheapest price, our data suggests you should book 21 weeks before departure.

Expert advice

Expert advice for your flight from St. Louis 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.
Our travel experts
Harriet Baskas

Harriet Baskas

Expert on BWI

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.

Yulia Denisyuk

Yulia Denisyuk

Expert on STL

Yulia is a freelance journalist who’s dispatched from 90+ countries. Her work focuses on cultures, adventure trips and air travel, appearing in NatGeo, NYT, CNTraveler, and more. For past assignments, she’s stayed with nomads in Mongolia and learned the art of Imigongo in Rwanda. She’s based in Chicago; in winter she often questions that decision.

Good to know

Low seasonJanuary
Cheapest flight$70
Best time to beat the crowds but there is an average 2% increase in price.
Most popular time to fly and prices are also 5% lower on average.
Flight from St. Louis to Baltimore

When to book flights from St. Louis to Baltimore

Are your dates flexible? Find out the best times to travel from St. Louis 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 St. Louis to Baltimore

  • What is the cheapest flight from St. Louis to Baltimore?

    In the last 5 days, the lowest price for a flight from St. Louis to Baltimore was $70 for a one-way ticket and $138 for a round-trip.

  • Do I need a passport to fly between St. Louis and Baltimore?

    A passport is not required to fly from St. Louis to Baltimore.

  • Which airports will I be using when flying from St. Louis to Baltimore?

    When flying out of St. Louis you will be using Lambert-St Louis. You will be landing at Baltimore, also known as Baltimore/Washington.

  • Which airlines offer Wi-Fi service onboard planes from St. Louis to Baltimore?

    American Airlines, Delta, and JetBlue offer inflight Wi-Fi service on the St. Louis to Baltimore flight route.

  • Which aircraft models fly most regularly from St. Louis to Baltimore?

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

  • Which airline alliances offer flights from St. Louis to Baltimore?

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

  • On which days can I fly direct from St. Louis to Baltimore?

    There are nonstop flights from St. Louis to Baltimore on a daily basis.

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

    The two airlines most popular with KAYAK users for flights from St. Louis to Baltimore are Southwest and Delta. With an average price for the route of $425 and an overall rating of 7.9, Southwest is the most popular choice. Delta is also a great choice for the route, with an average price of $297 and an overall rating of 7.9.

  • How does KAYAK find such low prices on flights from St. Louis 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 St. Louis to Baltimore.

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

    KAYAK’s flight Price Forecast tool uses historical data to determine whether the price for a flight to Baltimore from St. Louis 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 St. Louis 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 St. Louis with another airline. Booking your flights between St. Louis 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 St. Louis 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 St. Louis 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 St. Louis to Baltimore

  • Looking for a cheap flight? 25% of our users found flights on this route for $222 or less one-way and $403 or less round-trip.

Prefer to fly direct from St. Louis to Baltimore?

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

Direct departures

Lambert-St Louis 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 Lambert-St Louis

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 4 airlines serving from St. Louis to Baltimore

 
See real verified KAYAK customer reviews for airlines flying from St. Louis 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 St. Louis 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.
7.9
SouthwestOverall score based on 4235 reviews
7.5Entertainment
8.0Comfort
8.1Boarding
8.6Crew
7.0Food
Airline reviews

Flight coming out of Buffalo was delayed, so we had to be rescheduled on another flight from Baltimore to Phoenix which means we had a long layover and got home 3.5 hours late. Shuttle to parking stopped at 10pm, so we had to pay for an Uber to the parking lot and got charged an extra day of parking since it was after midnight. Not the best experience. Long day!

2.0 MediocreDawn, Jun 2026
BUF - BWI
Read more Southwest reviews

Flight coming out of Buffalo was delayed, so we had to be rescheduled on another flight from Baltimore to Phoenix which means we had a long layover and got home 3.5 hours late. Shuttle to parking stopped at 10pm, so we had to pay for an Uber to the parking lot and got charged an extra day of parking since it was after midnight. Not the best experience. Long day!

Terrible all around. Left prior review detailing massive delay/cancellation to then rebook travel. Topping on the cake was lost luggage even after travel to ultimate destination was secured on a new plane(s).

The flight was okay. The pilots did an amazing job and kept us updated on the flight. The flight attendants were okay. They found time to be chatty with each other rather than focus on the guests. One of the attendants was a little less warm when asking about my bag I had on my lap that I was using during latter part of the mid- flight. Mind you, it was not the departure descent. I’m respectful to each and every attendant, it was the tone in her voice reminding me to place my carryon bag on the floor. I hope to have a better experience next time.

I am very please with the service received from Southwest. Although there was a refuel stop in Fl before we got the Baltimore. The service and kindness of the staff was excellent.

Southwest continues to do less for more money. Flight attendants used to be fun and friendly. But now it’s like they don’t even see you. Such a shame.

I liked it better when you were truer to your roots Am paying more for less fun

We had a 5 hour delay on the tarmac in Baltimore

Long layover between flights to Long Island from BWI - need better coordination between flights

Snacks are always pretzels. Why can't you also offer peanuts ?

The last 3 flights between BWI and BDL canceled the beverage service mid- way. Just say up front that the fight is too short. Thanks!

Be on time? When not on time a circling for over an hour offer more than 1 bag of chips to the passengers? It was a 7 hour flight by the time we got done.

Five hour delays every hour, I wish it were all at once

Flight delayed four separate times. I’m now one hour hours late to landing.

worst flight ever from Delta, it got delayed and kept on delaying..

Should never have had to go to Detroit from Orlando back to Tennessee!

Got rerouted from a straight flight from Orlando to Atlanta to Knoxville to a flight from Orlando to Detroit to Knoxville! Seriously!! Flight delay out of Detroit! Long day for what should have been a pretty easy travel day!

Two delays on two separate planes with parts they could not easily find and replace.

Checkin was good, fllight ws good. Onlly complaint is lack of foot on 6 hour flight from Seattle to Boston. Snacks were flimsy - chips and cookies. could have offered something more substantial for such a long flight. I know you can buy food in airport but for the price you pay for a ticket, they should step up for the passengers.

Only beverages were offered to first class and I thought the flight attendant could have also served the Delta Comfort as well instead of sitting down and staring at her phone and walking past all of us to the back of the plane to charge her phone more. There was a complete lack of turbulence and was safe enough for flights attendant to walk around in the front of the plane, collect trash and serve a few people water and turn off the seat belt light. Also didn’t enforce people putting their seats into the upright position and allowed two passengers to remain reclined during landing. They seemed out to lunch completely. Usually my experience on Delta is much better.

Long story short, it was one of the better flight experiences I've had in some time when compared with other airlines.

Flight was delayed by 6 hours... the level of incompetence was truly astounding. I won't be flying American Airlines again. I don't care if AA is direct and there is a layover with another airline, I'll take the layover.

Leave on time. We waited on the plane for hour hours and it was hot and smelly

Two hours delay, probably one hour because they didn’t bring catering and they had to bring water in board. There a change of aircraft. But delays galore at CLT so it must be a CLT and/or AA operation issue. The 1 hr additional delays because nobody could bring 2 packs of water sooner is probably the best example of this airline operates

Flight was delayed 5 hours. Initial reason for delay was 'maintenance' - which makes sense. Then, the additional 2 hours continued to say it was maintenance - when I know EWR had a 2 hour delay. AA did not say that. Additionally, when boarding, there was only one agent at the counter for a long time - until another came to help. After boarding, we had to wait another 45 minutes due to 'no catering'. So while we waited for catering, AA continued to board additional passengers - which seemed odd - and raised questions about what really was going on. I sat in First Class. During the flight, the flight crew allowed a significant number of non-First Class passengers to use the front bathroom - which created a very crowded environment in First Class which was uncomfortable. This also delayed First Class passengers from using the bathroom. Overall, horrible experience.

The Charleston, WV airport was cute. Very good staff and small enough to feel comfortable. The plane had more leg room than bigger planes. Much more comfortable.

Another uncoordinated American experience. Always surprises me at DFW for them of all places. Have to take this flight as there are no other good time options. We knew from the start that something was wrong, but the pilot wouldn't tell us. I just watched my Kayak app grow the delay by 10 minutes as it went to 3.5 hours. They were uncoordinated with maintenance (as maintenance, when finally arriving, knew within 15 minutes the plane wasn't going. No 'sorry' or 'this is what is going on' comment. The pilot seemed unfazed / didn't care about the process we were going through.

The seats. The seat in front of me was awful and when the guy sat down, it flew back and hit my head when I was putting my backpack under the seat, It didn't make for a pleasant experience,

I’ve got 31F seat and window seat . My 2 co passengers was AA crew members and they were very rude attitude and when I was going to use bathroom their gestures was very different and awkward and the guy beside me completely occupied the hand rest and I was really uncomfortable

The gate experience at LAX was abysmal (same for the arrival experience two days prior). Despite the LAX -> SAT schedule of two flights daily, our departure gate was at a smaller hub that we had to be bussed to from Terminal 4. Fortunately, I arrived at LAX extra early and had time to spare, but if I had not known, I might have missed my flight. I looked at the LAX airport map in the AA app and there was no indication of the additional boarding process. Lastly the gate area we were bussed to was crowded with limited food and beverage options. On flight, the fight attendant was hospitable and attentive, the flight was smooth, and AA's free (and working) wifi for AA members were all on the positive side.

It was so much better than expected, Ohare is not such a pleasant experience but American Airlines with the new, clean aeroplane and free Wi-Fi was outstanding and the crew so pleasant and helpful.

There weren't enough employees at check in took awhile to get bags checked. There wasn't a wheel chair for me, I was sent to someone who turns out to work for a different airline, if My flight hadn't been delayed I probably would have missed my flight as it was, by the time I arrived at my gate, they started boarding in about 15 minutes. I don't know who took me to my gate, definitely was not the normal people who take passengers to the gate. I'm guessing she may have been in a management position. I wish I knew her name, she went beyond to help me. With that said everyone was kind, and were doing the best they could. So, I choose to say it was an Adventure, stressful start, but good. In the end went well. The situation was not only difficult for passengers but the employee's.

The staff at the check in counter was so rude. Made you feel Incompetent

Frontier scheduled a 40 minute connection in DEN. What they failed to mention was that they “close the doors” 20 mins prior to departure, which means you only have 20 mins. Not enough time. Possibly against DOT regulations. Filing complaint.

Flight was scheduled at 9:40pm. Got delayed to 10 am, the next day. crazy

The bag check, flight check-in, and onboard experience convinced my wife and me that we will actively go out of our way to avoid flying Frontier Airlines in the future. At bag check, we were informed that check-in could only be completed via the Frontier mobile app. Unfortunately, the app was extremely frustrating—sending us through repetitive, confusing loops that repeatedly forced us to decline add-on services with nearly every click. While most airline apps upsell, this one felt intentionally exhausting. As the process dragged on, we became genuinely concerned that my phone battery would die before check-in could be completed. We approached the bag check staff—who were standing together talking—and explained both our frustration and our predicament. They laughed. Later, my wife described the interaction as “gaslighting,” which felt accurate. We were then informed it would cost $25 per person simply to have our boarding passes printed. From that point forward, the tone of the experience was consistently hostile. The bag check employees were condescending and combative, behaving more like bullies than customer service staff. Unfortunately, that same attitude continued onboard. One flight attendant argued with me when I attempted to stow my backpack in the overhead bin. I explained that we had each paid $75 to check our bags specifically so we would not need to use carry-on space and could have adequate legroom. She demanded to see my ticket, pointed out that it said “no carry-on”—which I acknowledged—and I reiterated that this was precisely why we paid to check our bags. Her response was, “I don’t make the rules.” She then walked away, but not before asking if I “truly wanted to fly back to Chicago today?”—an unnecessary and unmistakable threat. It is also worth noting that despite booking our tickets together in the same transaction, we were not seated together. Upon our return to Chicago—where we could once again sit together—we compared onboard experiences. We both remarked on how unhappy the flight attendants appeared and how each of us was separately asked whether we would like to purchase a beverage. We declined. At no point was water mentioned as an option, leaving us with the clear impression that even water came at a cost—or that complimentary water, if available at all, was deliberately left unmentioned. Overall, the experience was shocking and deeply disappointing, but it was also a profound learning experience—one we will not forget and will not repeat. -Steve

Plane was hot and miserable and the crew was rude!

12 hour delay required getting on and off plane 3 times - would have at least liked to have been offered a snack or drink

They didn’t offer a water, even after I asked

They switched our terminal 3 times and we were delayed for four plus hours!!!

It was an early flight and most people napped/slept and the crew let us which was nice.

Everything you need to know for your flight from St. Louis to Baltimore

Information on your arrival and departure airports