BOI - STL

$111 Find Cheap Flights from Boise to St. Louis - Compare and Save

This is the cheapest one-way flight price found by a KAYAK user in the last 72 hours by searching for a flight from Boise to St. Louis departing on 8/20. 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

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Everything you should know

Cheapest round-trip
$260
Typical prices: $278-$506
Frontier
Thu 9/10Wed 9/16
BOI - STL • 1 stop
Cheapest one-way
$111
Typical prices: $143-$274
Frontier
Thu 8/20
BOI - STL • 1 stop
Top airlines
Cheapest • from $260 (round-trip)
Best reviews • 8.0 score
Airline reviews
Airline reviews
+1
+1
Airline reviews
Airline reviews
+1
Nonstop flights
Not available
There are currently no direct flights between Boise and St. Louis. You'll need at least 1 connection.
Insights
Insights
Insights
Insights
Top layover airports
Cheapest • Avg $372 (round-trip)
Shortest trip • 5h 06m (one-way)
Insights
Insights
Insights
Insights
When to travel
Cheapest • 100% price drop
Most popular
Good to know
Good to know
+1
+1
Good to know
Good to know
+1
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We hope you love your trip to St. Louis!
Flight Deals
Booking Insights
Flight Deals

Cheap Flights from Boise to St. Louis (BOI-STL)

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

Thu, Sep 10 - Wed, Sep 16
Frontier Logo
2:50 pm - 11:17 am
BOI
-
STL
19h 27m
1 stop
Frontier Logo
12:17 pm - 1:55 pm
STL
-
BOI
26h 38m
1 stop
$260Frontier
Fri, Sep 11 - Wed, Sep 16
Frontier Logo
2:50 pm - 11:32 am
BOI
-
STL
19h 42m
1 stop
Frontier Logo
12:17 pm - 1:55 pm
STL
-
BOI
26h 38m
1 stop
$281Frontier
Mon, Oct 5 - Wed, Oct 7
Frontier Logo
2:50 pm - 11:32 am
BOI
-
STL
19h 42m
1 stop
Frontier Logo
12:17 pm - 2:57 pm
STL
-
BOI
27h 40m
1 stop
$291Frontier
Tue, Nov 10 - Thu, Nov 19
Delta Logo
10:37 am - 11:23 pm
BOI
-
STL
11h 46m
2 stops
Delta Logo
7:10 am - 6:37 pm
STL
-
BOI
12h 27m
2 stops
$323Delta
Sun, Nov 8 - Wed, Nov 18
Delta Logo
6:45 am - 5:44 pm
BOI
-
STL
9h 59m
2 stops
Delta Logo
2:20 pm - 10:26 pm
STL
-
BOI
9h 06m
2 stops
$364Delta
Tue, Nov 10 - Thu, Nov 19
Southwest Logo
1:10 pm - 6:35 pm
BOI
-
STL
4h 25m
1 stop
Southwest Logo
6:35 am - 11:00 am
STL
-
BOI
5h 25m
1 stop
$369Southwest
Mon, Nov 9 - Thu, Nov 19
Southwest Logo
3:55 pm - 10:25 pm
BOI
-
STL
5h 30m
1 stop
Southwest Logo
6:00 am - 12:00 pm
STL
-
BOI
7h 00m
1 stop
$369Southwest
Thu, Sep 10 - Tue, Sep 15
United Airlines Logo
2:41 pm - 11:31 pm
BOI
-
STL
7h 50m
1 stop
United Airlines Logo
4:40 pm - 9:45 pm
STL
-
BOI
6h 05m
1 stop
$369United Airlines
Sat, Sep 12 - Mon, Sep 28
Delta Logo
2:50 pm - 11:16 pm
BOI
-
STL
7h 26m
1 stop
Delta Logo
5:47 pm - 11:59 pm
STL
-
BOI
7h 12m
1 stop
$369Delta
Mon, Oct 5 - Wed, Oct 7
United Airlines Logo
5:30 pm - 11:44 pm
BOI
-
STL
5h 14m
1 stop
United Airlines Logo
5:10 am - 1:03 pm
STL
-
BOI
8h 53m
2 stops
$425United Airlines
Booking Insights

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

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

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

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

Flight prices are below average for this route right now.

Flights to St. Louis from Boise usually cost between $414 and $676 in September.
The lowest price found in the past 5 days was $260 on Frontier (Sep 10-Sep 16).

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

To calculate monthly average prices, KAYAK takes all prices for each month over the last year for round-trip flights from Boise to St. Louis, 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 Boise to St. Louis is February, where tickets cost $0 (return) on average. On the other hand, the most expensive months are March and November, where the average cost of round-trip tickets is $609 and $572 respectively.

Good to know

Low season

October

Cheapest flight

$111
Best time to beat the crowds with an average 18% drop in price.
Most popular time to fly with an average 13% increase in price.
Flight from Boise to St. Louis

When to book flights from Boise to St. Louis

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

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

    In the last 5 days, the lowest price for a flight from Boise to St. Louis was $111 for a one-way ticket and $260 for a round-trip.

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

    No

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

    When flying out of Boise you will be using Boise Air Term. Gowen Fld. You will be landing at St. Louis, also known as Lambert-St Louis.

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

    We unfortunately don’t have that data for this specific route.

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

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

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

    The two airlines most popular with KAYAK users for flights from Boise to St. Louis are Southwest and Delta. With an average price for the route of $502 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 $444 and an overall rating of 7.8.

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

    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 Boise to St. Louis.

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

    KAYAK’s flight Price Forecast tool uses historical data to determine whether the price for a flight to St. Louis from Boise 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 Boise to St. Louis?

    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 St. Louis with an airline and back to Boise with another airline. Booking your flights between Boise and STL 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 Boise to St. Louis?

    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 St. Louis from Boise up to 3 days before/after your preferred dates. You can then pick the flights that suit you best.

Reviews of the top 3 airlines serving from Boise to St. Louis

 
See real verified KAYAK customer reviews for airlines flying from Boise to St. Louis. 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 Boise to St. Louis? 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 4229 reviews
7.0Food
7.5Entertainment
8.6Crew
8.1Boarding
8.0Comfort
Airline reviews

I have roller bag with food and medication told me I couldn't bring on my 2nd flight today. 15 years flying with SW never an issue with that bag.

2.0 MediocreStuart, Mar 2026
HOU - STL
Read more Southwest reviews

I have roller bag with food and medication told me I couldn't bring on my 2nd flight today. 15 years flying with SW never an issue with that bag.

I have not flown Southwest in awhile and had a very pleasant experience. From ticketing to boarding to the flight. The flight left on time and landed ahead of schedule. It won't be so long next time!!

Everything went smoothly and we even arrived a little bit early.

Boarded on time but once we were ready for take off, the crew determined that, although every seat was taken, somehow someone was on the wrong flight. Delay, delay delay, announcements and ended up with one person checking EVERY ID against their passenger Manifest only to figure out it was a "clerical error." We departed 54 minutes late causing me to run in the St. Louis Airport to make my connection and lose the priority boarding spot I had paid for. Unnecessary delay.

Southwest's seats are the least comfortable I have ever sat in.

For my birthday trip this was my second time ever flying, this trip was the best.

Crew was great flight was great baggage claim was a failure. It took over 1 hour for bags to arrive. Poor communication poor effort when I spoke to the supervisor about the delay

Everything was great except the food. The pretzels are really crappy.

I had a front row middle. I am not a big person and I barely fit in between that seat! No place to put my arms, even though the guys on each side were not taking over the arm rests. It felt like a frontier flight (if that tells you everything )

Overall is was a pretty good flight. However we were 15 mins late taking off and no one told us anything. We were all in our seats just sitting there for 15mins and all the sudden the pilot stayed we are leaving now. I think they should have at least said something after our take off time passed. Everyone was wondering what was going on. I will say the pilot did increase the speed of the plane so we arrived in time. So we weren't late.

We departed early and made up time in the air allowing us to arrive 30 minutes early. Capt was incredibly genuine and thanked every passenger for flying with Delta. Completely humble and professional!

This flight was a first class choice and left much to be desired. Seat backs on seats were falling apart and torn. Seats actually didn't come to a "full & upright position". Pull out table was sprung. Not any significant leg room. All in all we were on an obviously older plane and felt overcharged for what we received as first class.

The boarding process needs to be refined. Sometimes the gate crew calls out the zones and then flip to showing the.zones boarding on the gate monitor display. So, unless you are huddled around the gate lanes watching the monitor, you could miss your boarding zone. Suggest the zones be announced each time a new zone is allowed to board.

This route with Delta always has delays or is cancelled. Aircrafts seem smaller and older. I fly Delta quite a bit - haven’t had issues with the international flights. But this route has always been the troublesome one

My husband is very tall and we generally fly Delta Comfort. We used our companion benefit, and our seats were coach and extremely uncomfortable........ horrid even

I specifically picked out right side aisle seats because my left knee sometimes needs to be stretched. But my experience this trip was that the seats were shuffled and I lost those assigned seats, resulting in me having to sit in a much less desirable position for my comfort.

On 2 different flights the wifi was horrible and there was no drink or snack service.

There was no FREE wi-fi nor entertainment screens at all.

Great, on time departure, friendly and accommodating crew, great leg room, Smith flight

As we lined up to board they gave our plane to a flight going to Newark. So then we got delayed until they could find another plane. Flight crew was ok. I’m assuming since it’s a shorter flight they only offered water and coffee.

Flight was delayed “due to earlier delays of that plane”, so we were nearly three hours late.

Crew was amazing, takeoff wonderful. The bathroom was disgusting from before takeoff the odor made the flight uncomfortable as you could smell the bathroom from the center of the plane where we were sitting. Smelled like raw sewage. My daughter was throwing up as we landed due to the smell and horrible turbulence as we approached Newark.

Delayed - weather wasn't bad at either end. Also sat on tarmac in ORD.

During landing. 2 crew members passed 3 times by my lane and didn't notice that people in front of us had their site to the furthermore reclined... That was uncomfortable and could have been dangerous.

Airport terminal was outdated, flight was on a small jet with no wifi

Essy to get on. The hostess gave very little pop, the plane was late getting in, and we are still waiting for our bags. This sucks. :/

Lately I like the planes have been exceptionally filthy. There’s lines of dust and dirt all across the ceiling in the vents, and the cracks in between the seats are literally full of food. It’s definitely not the quality of service that I was used to with United. I’m also very disappointed with the Wi-Fi! All I wanna do is knock out a few work jobs while I’m trapped in my seat And it spools so bad. They did provide me with a refund, but the process of getting that refund is so complicated. It’s unfortunate.

Excellent flight. Smooth, efficient boarding. Quick flight. Arrived early at STL.

United Airlines was fantastic, however, UnderPricer was a nightmare. I got to the airport 4 hours before my flight. We are moving to New Zealand so had quite a bit of baggage (16 checked items) and so wanted to have plenty of time to get everything taken care of properly. When I went to check in they (United) could only find a ticket for me. The 5 tickets for my children were never officially ticketed. I called Underpricer and they told me it was United's fault and United told me that Underpricer just needs to reissue the tickets, but they refused to. I asked the Underpricer agent to transfer me to his supervisor as I was not getting the help I needed. He told me the supervisor was busy but that he would call me back in 30 minutes. 30 minutes came and went with no phone call. After an hour I called Underpricer back but they would not let me talk to the person I had talked to before, just told me that he was talking with the supervisor and technical support. I called again an hour later, was told the same thing. I tried again later, with only about 30 minutes until my flight was scheduled to leave (meaning I had been at the airport for more than 3 hours with my 5 children trying to get ticketed and board the flight). Also, my husband had moved to New Zealand 3 months prior, I haven't seen him in 3 months, my children hadn't seen their dad in 3 months, we were all extremely eager to get on that flight and get to New Zealand. The situation with the tickets did not get resolved until after it was too late to check our luggage and board our flight. We were devastated. My 11 year old son was in tears at not being able to be on his way to see his dad. Thankfully we were rebooked for the next evening, but that night it felt devastating. We'd been at the airport for 4 hours waiting. My in-laws waited with me and then helped me reload all our baggage and took us home to stay with them for the night. On the newly booked flights we could not sit together - my children were spread throughout the plane. So, even though I had paid extra to select our seats after buying my seats from Underpricer only two of us were able to sit together (thankful that my 11 year old wasn't all by himself, but not happy that my 14 & 16 year old daughters were seated by strangers). I really feel that Underpricer should refund me what I paid for the seating ($120 USD). It was a very frustrating situation and I plan on never using Kayak or Underpricer ever again.

Last minute gate change nearly caused us to miss our flight. Change was not announced or displayed in the main board at the old gate. Terrible communication. When we landed we had to wait 20 minutes because there was another plane at the assigned gate. Not the crew’s fault, but adding 20 minutes to a 45 minute flight sucked.

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

Information on your arrival and departure airports