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 5/12. 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
Travelers love KAYAK
41,299,237 searches in the past 7 days on KAYAK

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Everything you should know

Cheapest round-trip
$145
Overall average: $307
Frontier
Tue 5/12Tue 5/19
STL - BWI • 1 stop
Cheapest non-stop
$343
Typical prices: $217-$467
Southwest
Sat 4/18Tue 4/21
STL - BWI • Non-stop
Advice from real travelers
AI-powered summary based on content written by travel experts. AI can make mistakes.
Avoid peak hours at STL for faster baggage claim.
Use the light rail from BWI to reach downtown Baltimore.
Expert advice
Expert advice
Expert advice
Expert advice
Nonstop flights
You can fly direct with Southwest. Average duration is 2h 00m
Direct flights
Direct flights
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Direct flights
Direct flights
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Top layover airports
Cheapest • Avg $230 (round-trip)
Shortest trip • 3h 30m (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 44% compared to booking last minute.
Insights
Insights
Insights
Insights
When to travel
Cheapest • 34% price drop
Most popular
Good to know
Good to know
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Start a new search
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 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, May 12 - Tue, May 19
Frontier Logo
6:33 pm - 7:43 am
STL
-
BWI
12h 10m
1 stop
Frontier Logo
9:25 pm - 8:55 am
BWI
-
STL
12h 30m
1 stop
$145Frontier
Wed, May 13 - Tue, May 19
Frontier Logo
5:27 pm - 7:43 am
STL
-
BWI
13h 16m
1 stop
Frontier Logo
9:25 pm - 8:55 am
BWI
-
STL
12h 30m
1 stop
$155Frontier
Mon, May 11 - Tue, May 19
Frontier Logo
5:27 pm - 7:43 am
STL
-
BWI
13h 16m
1 stop
Frontier Logo
9:25 pm - 8:55 am
BWI
-
STL
12h 30m
1 stop
$159Frontier
Mon, Apr 20 - Wed, Apr 29
Frontier Logo
8:23 pm - 11:22 am
STL
-
BWI
13h 59m
1 stop
Frontier Logo
5:49 pm - 10:26 am
BWI
-
STL
17h 37m
1 stop
$169Frontier
Wed, Apr 15 - Wed, Apr 22
Frontier Logo
8:23 pm - 8:02 am
STL
-
BWI
10h 39m
1 stop
Frontier Logo
5:49 pm - 10:30 am
BWI
-
STL
17h 41m
1 stop
$174Frontier
Fri, May 15 - Tue, May 19
Frontier Logo
5:27 pm - 7:43 am
STL
-
BWI
13h 16m
1 stop
Frontier Logo
9:25 pm - 8:55 am
BWI
-
STL
12h 30m
1 stop
$178Frontier
Wed, Apr 15 - Sat, Apr 18
Frontier Logo
8:23 pm - 8:02 am
STL
-
BWI
10h 39m
1 stop
Frontier Logo
5:45 pm - 11:19 pm
BWI
-
STL
6h 34m
1 stop
$180Frontier
Tue, May 5 - Mon, May 11
Frontier Logo
6:41 pm - 10:57 pm
STL
-
BWI
27h 16m
1 stop
Frontier Logo
9:25 pm - 5:33 pm
BWI
-
STL
21h 08m
1 stop
$181Frontier
Wed, Apr 15 - Wed, Apr 22
Frontier Logo
8:23 pm - 8:02 am
STL
-
BWI
10h 39m
1 stop
Frontier Logo
5:49 pm - 10:30 am
BWI
-
STL
17h 41m
1 stop
$186Frontier
Wed, Apr 22 - Tue, Apr 28
Frontier Logo
8:23 pm - 8:02 am
STL
-
BWI
10h 39m
1 stop
Frontier Logo
5:49 pm - 6:50 am
BWI
-
STL
14h 01m
1 stop
$190Frontier
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.

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 Sundays 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 Sundays.

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 $239 (return) on average. On the other hand, the most expensive months are February and March, where the average cost of round-trip tickets is $493 and $422 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 $298, 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 44% compared to booking last minute. For the absolute cheapest price, our data suggests you should book 11 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 12% increase in price.
Most popular time to fly and prices are also 15% 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 3 days, the lowest price for a flight from St. Louis to Baltimore was $70 for a one-way ticket and $145 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 $388 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 $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 $234 or less one-way and $383 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.
8.0
SouthwestOverall score based on 4320 reviews
8.0Comfort
8.1Boarding
8.6Crew
7.5Entertainment
7.0Food
Airline reviews

We had a 5 hour delay on the tarmac in Baltimore

2.0 MediocreDavid, Mar 2026
ALB - BWI
Read more Southwest reviews

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

I elected to pay for the upgrades and found very little difference

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!

Only downside was the legroom and seat width, which is always a problem unless I spend more for a premium seat.

I was assigned seat 7E, yet my boarding was Group 5, which caused me to have to put my luggage in the back of the plance above `19 or 20 aisle, as passengers who had boarded earlier took the overhead bins in the front. SW needs to monitor bin space and ensure that bin space above the seat are aligned to those sitting near their seats. Also the seating assignments needs to align with group number. Maybe board those last first and so on? Having said the ALL the passengers on the plane were gracious enough to allow me and other passengers in this dilema to retrieve our luggage and helped us along the way. I always love the flight staff, as always their fantastic and I can't rave about them enough!

WIFI was great. My selection for seating is an aisle, but during my trip, I never had an aisle seat. If we can get that corrected, I will be thrilled.

Departure was delayed more than 1/2 hour while we waited for luggage (only) transfer from another flight/plane. Once approved for takeoff, the flight was excellent.

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.

My flight was canceled on Sunday. Rebooking took three hours. Had to pay for accommodations another night. New flight was delayed for 5 hours, all that was sent was a 12 dollar food voucher, which doesn’t tell you how to use it. Then when we landed we had to sit on the plane for an hour before we could get off.

Miserable. This entire round trip was miserable. I booked evening flights to and from Detroit on consecutive days that should have had me at my destination by 10:30. Instead I arrived after 3am on my flight to Detroit and after midnight on my return. Multiple unforced errors like awaiting bags to get put on the plane for almost an hour in Detroit and a 20 minute delay to pull up to the gate in Atlanta has me rethinking my assumption that delta is the best and most reliable airline

Perhaps when you’re sitting in 1st class and the crew closes the bathroom for the pilots, there could be a notification other than holding your hands up as a blockade when you get there and you’re told the restrooms are closed please turn around … especially at night when visibility is poor and you’re met by a flight attendants with their arms up

First class is comfortable. Enjoyed a movie and was able to relax compared to coach.

Loved flying First Class. Very comfortable. The seat was amazing. Enjoyed a movie and was able to relax so much better than in coach.

We landed and sat on the tarmac for 45 minutes because they only have one gate at the airport and there was another plane running late so we had to wait

The WiFi was not working. That made for a long flight.

Absolutely no communication on why there's a delay and multiple flight time reschedules. I would have canceled the flight and drove back home if I known it was going to be rescheduled 3 or 4 times.

Another late night flight and MORE men belligerently drinking and yelling. I had to move from first to economy because they were so obnoxious and disruptive. Crazy to go from a cozy chair to cardboard when you were supposed to be in first. Delta allows was too much drinking which leads to belligerent behavior.

I was in first class and literally the men behind me were so aggressively loud I moved myself to economy. This has become so common on Delta - people using audio without headphones, and men on 12am / late night flights drinking and yelling to talk to each other which prevents anyone around them from resting. Pretty crazy to have to move from first to economy (poorer service, less comfort...). Wild wild. Looking into other airlines.

The business steward was absolutely amazing! Smiles and kindness! Wish all AA flights are like this one!

As a first class customer, there was no power the entire flight which limited my ability to work. I find this unacceptable. The first 11 rows on the left side of the plan were out. I was only offered the option to charge my phone which was not the issue because my laptop was out of power. I asked if there was anything that can be done for me, and the answer was, "no". I was not offered any type of compensation for this AA problem which caused me unnecessary stress due to inability to address business issues on an already challenging travel day. Flight attendants tried to reset the power once but that was the extent of their support. Very disappointing for the lack of expected services on a flight. Please contact me with customer focused response to this complaint.

Delay after delay with little communication then AA lost my luggage and at airport would not assist just said scan this QR code to track your luggage and submit a claim. However QR code provided did not work so have to go back to airport

After changing the departure gate 5 times making us mo e from one side of the airport to the other and then back the flight was delayed nearly 2 hours. The male flight attendant had a bad attitude with the guest being condescending, disrespectful with people who were already on edge.

Easy boarding. Rows are smaller but that may be an older and bigger me now :)

It would have been nice if American tried to care.

American Airlines did everything they could with the high Spring Break crowd. I was frustrated to be changed from 1st class to a middle seat at the back of the plane. This has happened before, not sure booking 1st class and paying the extra actually works.

I booked 1st class, my flights were changed and I was sitting in the middle at the back of the plane. A far cry from the 1st class I purchased for my flights. I am grateful I arrived on time.

There was no beverage service and the only time I saw a crew member walk through the cabin is when we were preparing to land.

Our flight was delayed 3 times and this is why I am giving such low reviews. Everything else was okay but being in the airport at 4:30pm for my initial flight at 7pm to not leave until after 9:30pm is insane,

More inflight connection. And leg space is horrible. And the paying for baggage I'd ridiculous!!!

My flight was originally from SAT to MCO connecting from MCO to ORD. We got diverted to ATL and than Frontier staff there was sooo un helpful first they said they couldn’t give us any accommodation since our flight first got delayed that cancelled and now it’s 221am and I am still in ATL since they said they need to create a new flight my final destination is ORD and I have been delayed twice and cancelled. With no real help the frontier app didn’t work no email updates over all such a horrible experience

There's no seats that lean back with little leg space i wad uncomfortable the entire flight. Your charges for extra baggage is despicable and costly!!

Remind customers of the need to have passport or new ID for boarding.

Flight was canceled. Most upsetting was message from Kayak, stating that the flight was canceled and click with Kayak for details regarding rebook, refund details. THERE'S NO INFORMATION PROVIDED BY KAYAK EXCEPT THAT FLIGHT IS CANCELED. AND NOW THIS SURVEY TO FIND OUT HOW WAS THE FLIGHT !!!!!!!

The flight never took off and we spent 7 hours at the airport

Gate not determined until I got to the airport - hard to plan the trip to the airport.

Our flight was canceled. I will never use Kayak nor Frontier for travel again. The entire experience was a headache.

Frontier.. nickel and dime add-ons. Flight late, on time, late again, last minute gate change, arrival gate required a shuttle to the terminal. They sure keep you guessing.. if you like a little chaos and airport anxiety, this is the airline for you!

This is my second time flying with Frontier. My current experience was very favorable. The staff from the gate to the plane was friendly, warm and professional. The food options lacked in my opinion. This area needs some attention in my opinion.

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

Information on your arrival and departure airports