Cheap flights from St. Louis to Helena from $442

This is the cheapest round-trip flight price found by a momondo user in the last 72 hours by searching for a flight from St. Louis to Helena departing on 2/4. Fares may change, and may not be available for all flights or travel dates. Click the price to refresh the search for this deal.
1 adult
0 bags

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Cheap round-trip flights

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Alaska Airlines Logo
2:50 pm - 6:11 pm
STL
-
HLN
28h 21m1 stop
Alaska Airlines Logo
6:48 pm - 1:54 pm
HLN
-
STL
18h 06m1 stop
$442Alaska Airlines
Wed, Feb 4 - Sat, Feb 7
Alaska Airlines Logo
7:04 am - 6:11 pm
STL
-
HLN
12h 07m2 stops
Alaska Airlines Logo
6:48 pm - 1:54 pm
HLN
-
STL
18h 06m1 stop
$529Alaska Airlines
Wed, Feb 4 - Sat, Feb 7
Alaska Airlines Logo
7:04 am - 6:11 pm
STL
-
HLN
12h 07m2 stops
Alaska Airlines Logo
6:48 pm - 7:29 pm
HLN
-
STL
23h 41m2 stops
$534Alaska Airlines
Wed, Feb 4 - Sat, Feb 7

Alaska Airlines flights from St. Louis to Helena

Our best Alaska Airlines deals on St. Louis to Helena flight tickets
Alaska Airlines
Feb 4
STL2:50 pmLambert-St Louis
28h 21m
1 stop
HLN6:11 pmHelena
Feb 7
HLN6:48 pmHelena
18h 06m
1 stop
STL1:54 pmLambert-St Louis
Alaska Airlines
Feb 4
STL7:04 amLambert-St Louis
12h 07m
2 stops
HLN6:11 pmHelena
Feb 7
HLN6:48 pmHelena
18h 06m
1 stop
STL1:54 pmLambert-St Louis
Alaska Airlines
Feb 4
STL7:04 amLambert-St Louis
12h 07m
2 stops
HLN6:11 pmHelena
Feb 7
HLN6:48 pmHelena
23h 41m
2 stops
STL7:29 pmLambert-St Louis

Delta flights from St. Louis to Helena

Our best Delta deals on St. Louis to Helena flight tickets
Delta
Dec 13
STL5:00 pmLambert-St Louis
6h 30m
1 stop
HLN10:30 pmHelena
Dec 15
HLN1:06 pmHelena
9h 23m
2 stops
STL11:29 pmLambert-St Louis
Delta
Dec 13
STL11:19 amLambert-St Louis
12h 11m
2 stops
HLN10:30 pmHelena
Dec 15
HLN5:30 amHelena
10h 19m
2 stops
STL4:49 pmLambert-St Louis

momondo Fare Finder

 
Customize your flight search to find flights from St. Louis to Helena that fit within your specific budget. Explore options based on user searches and filter the results based on your desired price range. Find flights that match your budget for a cost-effective journey. Over the last 7 days, momondo users made 832,500 searches. Data last updated December 11, 2025.
Use the filters below to find and compare flights from St. Louis to Helena that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

St. LouisHelena

STL - HLN

STLHLN

Lambert-St Louis

Wed 2/4

2:50 pm-6:11 pm

1 stop28h 21m

Helena

Sat 2/7

6:48 pm-1:54 pm

1 stop18h 06m

$442

St. LouisHelena

STL - HLN

STLHLN

Lambert-St Louis

Wed 2/4

7:04 am-6:11 pm

2 stops12h 07m

Helena

Sat 2/7

6:48 pm-1:54 pm

1 stop18h 06m

$529

St. LouisHelena

STL - HLN

STLHLN

Lambert-St Louis

Wed 2/4

7:04 am-6:11 pm

2 stops12h 07m

Helena

Sat 2/7

6:48 pm-7:29 pm

2 stops23h 41m

$534

Flights are sorted by cheapest round-trip flights first.

Sorted by cheapest first

See travel insights to Helena from

How to get the cheapest flight ticket from St. Louis to Helena

Look no further. We've gone through all the searches for this route on momondo so you have the important information and insights to find the cheapest flight ticket for your trip

What is the cheapest day to depart on your flight to Helena?

The cheapest day to depart from St. Louis to Helena is on a Tuesday. Travelers who choose to depart for Helena on a Tuesday will often find tickets for as low as $448. The most expensive day to fly to Helena is Thursday, with ticket prices averaging around $760.

What is the cheapest time of day to depart on your flight to Helena?

According to our data, the cheapest time of day to fly to Helena is in the morning. momondo users have found flights departing from St. Louis to Helena in the morning for as low as $538. Keep in mind that these prices may fluctuate based on what airline you choose and the time of year you plan to travel. In contrast, the most expensive time of day to depart to Helena is in the afternoon when prices are around $888.

When to book flights from St. Louis to Helena

Are you open to changing your travel dates? Check out the ideal times to fly from St. Louis to Helena according to our flight data. Find out which month and days have the cheapest flights.
Estimated round-trip price

Cheap St. Louis to Helena (STL to HLN) flight deals and tips

Find info about flight duration, direct flights, and airports for your flight from St. Louis to Helena

Fastest flight time

5h 45m

Direct flights

None
The fastest flight from St. Louis to Helena takes 5h 45m
There are no direct flights from St. Louis to Helena. There are no popular flight routes from St. Louis to Helena.
  • How far is Lambert-St Louis to Helena by plane?

    The distance between Lambert-St Louis and Helena is about 1232.9 mi. Flights usually cover this in 5h 45m, depending on flying conditions and air traffic around both airports.

  • When did momondo last update prices for flights from Lambert-St Louis Airport to Helena Airport?

    Prices for flights from Lambert-St Louis Airport to Helena Airport are refreshed on a daily basis.

  • How old do you have to be to fly from Lambert-St Louis Airport to Helena Airport?

    Although the minimum age for a child to fly alone is five, airlines that offer an unaccompanied minor (UMNR) service may have their own age limits, which could be impacted by factors such as flight length, timing, and layovers. It is recommended that you verify with the airline you are booking with for travel from Lambert-St Louis Airport to Helena Airport.

  • What documentation or ID do you need to fly to Helena Airport?

    The necessary travel and health documents for your Helena Airport trip may vary depending on your travel plans and individual circumstances. Generally, you should have various documents, such as a national ID card or driver's license and a passport that is valid for six months beyond your scheduled arrival date. We recommend seeking advice from your airline or a trusted third party, such as IATA.

Why use momondo?

Why should I use momondo to find a flight deal from St. Louis to Helena?

We help find the flight that best suits your needs, momondo compares prices from hundreds of airlines and travel agents and helps you filter them to find the best flight from St. Louis to Helena for you.

Can I find flights from St. Louis to Helena with flexible booking policies on momondo?

momondo does allow users to show only those flights to Helena from St. Louis which offer a flexible booking policy as well as other useful filters and features.

How can momondo help me find flights from St. Louis to Helena?

Once all potential St. Louis to Helena flight options are in front of you, momondo lets you sort and filter flights based on preferences such as airline, price and flight times amongst many other options.

I’m not ready to book a flight from St. Louis to Helena right now. Can momondo alert me if prices change?

Yes momondo offers price alerts on flights to Helena from St. Louis. After performing a search on this page you should be able to see the price alert set up feature. Simply provide a valid email address and momondo will instantly alert you when prices change.

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1 adult
Sat 1/10
Sat 1/17

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