Cheap flights from the United States to St. Louis from $43

This is the cheapest one-way flight price found by a momondo user in the last 72 hours by searching for a flight from the United States to St. Louis departing on 4/3. 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
1 adult, Economy, 0 bags

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Find the cheapest flights from the United States to St. Louis

Recent round-trip flight deals from the United States to St. Louis

Enter your travel dates to find the best prices.
Frontier Logo
6:40 am - 9:48 am
DEN
-
STL
2h 08mnonstop
Frontier Logo
8:19 pm - 9:52 pm
STL
-
DEN
2h 33mnonstop
$107Frontier
Wed, Apr 1 - Mon, Apr 6
Frontier Logo
4:09 pm - 7:21 pm
DEN
-
STL
2h 12mnonstop
Frontier Logo
8:06 pm - 9:39 pm
STL
-
DEN
2h 33mnonstop
$111Frontier
Thu, Apr 16 - Thu, Apr 23
American Airlines Logo
3:17 pm - 11:46 pm
SEA
-
STL
6h 29m
1 stop
American Airlines Logo
7:05 am - 12:29 pm
STL
-
SEA
7h 24m
1 stop
$237American Airlines
Wed, Apr 8 - Wed, Apr 22
American Airlines Logo
3:17 pm - 11:46 pm
SEA
-
STL
6h 29m
1 stop
American Airlines Logo
5:21 pm - 10:38 pm
STL
-
SEA
7h 17m
1 stop
$243American Airlines
Thu, Apr 9 - Tue, Apr 14
Southwest Logo
5:20 pm - 1:50 am
SEA
-
STL
6h 30m
1 stop
Southwest Logo
5:20 pm - 11:30 pm
STL
-
SEA
8h 10m
1 stop
$244Southwest
Fri, Jun 5 - Tue, Jun 9
Southwest Logo
8:25 am - 8:10 pm
SEA
-
STL
9h 45m
1 stop
Southwest Logo
3:55 pm - 10:30 pm
STL
-
SEA
8h 35m
1 stop
$249Southwest
Tue, Apr 14 - Tue, Apr 21
Delta Logo
4:36 pm - 12:25 am
SEA
-
STL
5h 49m
1 stop
Delta Logo
6:45 pm - 11:59 pm
STL
-
SEA
7h 14m
1 stop
$253Delta
Mon, May 4 - Wed, May 6
United Airlines Logo
9:00 am - 10:28 am
IAD
-
STL
2h 28mnonstop
United Airlines Logo
9:10 am - 4:03 pm
STL
-
IAD
5h 53m
1 stop
$275United Airlines
Thu, Apr 16 - Mon, Apr 20
Delta Logo
6:20 am - 11:56 am
JFK
-
STL
6h 36m
1 stop
Delta Logo
4:41 pm - 12:48 am
STL
-
JFK
7h 07m
1 stop
$293Delta
Tue, Apr 21 - Tue, Apr 21
United Airlines Logo
10:07 pm - 11:35 pm
EWR
-
STL
2h 28mnonstop
United Airlines Logo
5:33 pm - 11:39 pm
STL
-
EWR
5h 06m
1 stop
$339United Airlines
Wed, Jun 24 - Fri, Jun 26

Frontier flights from United States to St. Louis

Our best Frontier deals on United States to St. Louis flight tickets
Frontier
Apr 1
DEN6:40 amDenver Intl
2h 08m
STL9:48 amLambert-St Louis
Apr 6
STL8:19 pmLambert-St Louis
2h 33m
DEN9:52 pmDenver Intl
$107
Frontier
Apr 16
DEN4:09 pmDenver Intl
2h 12m
STL7:21 pmLambert-St Louis
Apr 23
STL8:06 pmLambert-St Louis
2h 33m
DEN9:39 pmDenver Intl
$111
Frontier
Apr 18
DEN4:20 pmDenver Intl
2h 12m
STL7:32 pmLambert-St Louis
Apr 20
STL9:55 pmLambert-St Louis
7h 04m
1 stop
DEN3:59 amDenver Intl
$114

American Airlines flights from United States to St. Louis

Our best American Airlines deals on United States to St. Louis flight tickets
American Airlines
Apr 9
SEA3:17 pmSeattle/Tacoma Intl
6h 29m
1 stop
STL11:46 pmLambert-St Louis
Apr 14
STL5:21 pmLambert-St Louis
7h 17m
1 stop
SEA10:38 pmSeattle/Tacoma Intl
$243
American Airlines
Apr 28
DFW9:10 pmDallas/Fort Worth
1h 49m
STL10:59 pmLambert-St Louis
Apr 30
STL7:12 amLambert-St Louis
2h 08m
DFW9:20 amDallas/Fort Worth
$263
American Airlines
Apr 25
DFW3:35 pmDallas/Fort Worth
1h 46m
STL5:21 pmLambert-St Louis
Apr 27
STL3:38 pmLambert-St Louis
2h 01m
DFW5:39 pmDallas/Fort Worth
$265

momondo Fare Finder

 
Customize your flight search to find flights from United States to St. Louis 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 March 21, 2026.
Use the filters below to find and compare flights from the United States to St. Louis that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

Cheapest round-trip
Quickest round-trip

DenverSt. Louis

DEN - STL

DENSTL

Denver Intl

Wed 4/1

6:40 am-9:48 am

Nonstop2h 08m

Lambert-St Louis

Mon 4/6

8:19 pm-9:52 pm

Nonstop2h 33m

$107

DenverSt. Louis

DEN - STL

DENSTL

Denver Intl

Thu 4/16

4:09 pm-7:21 pm

Nonstop2h 12m

Lambert-St Louis

Thu 4/23

8:06 pm-9:39 pm

Nonstop2h 33m

$111

SeattleSt. Louis

SEA - STL

SEASTL

Seattle/Tacoma Intl

Wed 4/8

3:17 pm-11:46 pm

1 stop6h 29m

Lambert-St Louis

Wed 4/22

7:05 am-12:29 pm

1 stop7h 24m

$237

SeattleSt. Louis

SEA - STL

SEASTL

Seattle/Tacoma Intl

Thu 4/9

3:17 pm-11:46 pm

1 stop6h 29m

Lambert-St Louis

Tue 4/14

5:21 pm-10:38 pm

1 stop7h 17m

$243

SeattleSt. Louis

SEA - STL

SEASTL

Seattle/Tacoma Intl

Fri 6/5

5:20 pm-1:50 am

1 stop6h 30m

Lambert-St Louis

Tue 6/9

5:20 pm-11:30 pm

1 stop8h 10m

$244

SeattleSt. Louis

SEA - STL

SEASTL

Seattle/Tacoma Intl

Tue 4/14

8:25 am-8:10 pm

1 stop9h 45m

Lambert-St Louis

Tue 4/21

3:55 pm-10:30 pm

1 stop8h 35m

$249

SeattleSt. Louis

SEA - STL

SEASTL

Seattle/Tacoma Intl

Mon 5/4

4:36 pm-12:25 am

1 stop5h 49m

Lambert-St Louis

Wed 5/6

6:45 pm-11:59 pm

1 stop7h 14m

$253

Washington, D.C.St. Louis

IAD - STL

IADSTL

Washington, D.C. Dulles Intl

Thu 4/16

9:00 am-10:28 am

Nonstop2h 28m

Lambert-St Louis

Mon 4/20

9:10 am-4:03 pm

1 stop5h 53m

$275

New YorkSt. Louis

JFK - STL

JFKSTL

New York John F Kennedy Intl

Tue 4/21

6:20 am-11:56 am

1 stop6h 36m

Lambert-St Louis

Tue 4/21

4:41 pm-12:48 am

1 stop7h 07m

$293

NewarkSt. Louis

EWR - STL

EWRSTL

Newark

Wed 6/24

10:07 pm-11:35 pm

Nonstop2h 28m

Lambert-St Louis

Fri 6/26

5:33 pm-11:39 pm

1 stop5h 06m

$339

Flights are sorted by cheapest round-trip flights first.

Showing 1-10 of 20 resultsSorted by cheapest first
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See travel insights to St. Louis from

How to get the cheapest flight ticket from United States to St. Louis

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 month to fly to St. Louis?

In general, August is the cheapest month to fly from United States to St. Louis. Due to it being the ‘off-season’ during this time, you can expect flight prices to be around $306. The month of June is another great option to travel to St. Louis, with average flight prices from United States averaging around $312.

What is the cheapest day to depart on your flight to St. Louis?

The cheapest day to depart on your flight to St. Louis is on a Wednesday when prices can be found for as low as $323. This is often the case because there is less demand to fly during this day of the week. If your travel schedule is flexible, try to avoid departing on a Sunday because tickets tend to average around $447. These prices are subject to change though, so be sure to set up a Price Alert for flights to St. Louis.

What is the cheapest time of day to depart on your flight to St. Louis?

Flying to St. Louis from United States in the morning is the least expensive time of day to depart. momondo users have found prices as low as $357 when looking at flights departing in the morning. At noon is when there is more demand to fly to St. Louis, so prices are often more expensive at around $373 per ticket.

What is the cheapest United States to Lambert-St Louis flight route?

Fly from Dallas/Fort Worth to Lambert-St Louis for the best United States - Lambert-St Louis flight prices

What cabin class options are available on United States to Lambert-St Louis flights?

There are 4 cabin classes available to choose from on United States to Lambert-St Louis flights. Cabin price and availability will vary by airline so perform a search above to find the right deals for you.

Can stopping save me money on United States to St. Louis flights?

No. A direct flight is the cheapest option for a flight between United States to St. Louis.

Cheap United States to St. Louis flight deals and tips

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

Best Price Found

$135

Fastest flight time

1h 05m

Direct flights

Every day

Airports in St. Louis

1 airport
The best one-way flight to St. Louis from United States in the past 72 hours is $135. The best round-trip flight deal from United States to St. Louis found on momondo in the last 72 hours is $61.
The fastest flight from United States to St. Louis takes 1h 05m
Direct flights go from United States to St. Louis every day.
There is 1 airport in St. Louis. From United States there are direct flights to Lambert-St Louis (STL).
  • When did momondo last update prices for flights from United States to Lambert-St Louis Airport?

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

  • How many operators does momondo search for flights from United States to Lambert-St Louis Airport?

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

    The minimum age a child must be to fly alone is five but airlines that offer an unaccompanied minor (UNMR) service will have their own age restrictions, including rules around flight length, timings, and stopovers. We always recommend checking with the individual airline you are booking with to travel from United States to Lambert-St Louis Airport.

  • What documentation or ID do you need to fly to Lambert-St Louis Airport?

    The necessary travel and health documents for your Lambert-St Louis 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.

  • What is the most popular plane model from United States to St. Louis?

Best airlines flying from United States to St. Louis

Compare and see reviews for airlines that fly from United States to St. Louis with momondo
Airline
Rating
Free Cancellation
Price
Spirit AirlinesPriceFrom $54Free CancellationRating
6.3
8,532 reviews
Search Spirit Airlines flights
FrontierPriceFrom $54Free CancellationRating
5.7
3,022 reviews
Search Frontier flights
DeltaPriceFrom $116Free CancellationRating
7.9
8,312 reviews
Search Delta flights
American AirlinesPriceFrom $144Free CancellationRating
7.1
11,487 reviews
Search American Airlines flights
United AirlinesPriceFrom $166Free CancellationRating
7.4
9,451 reviews
Search United Airlines flights
SouthwestPriceFrom $171Free CancellationRating
8.0
4,325 reviews
Search Southwest flights
JetBluePriceFrom $243Free CancellationRating
7.2
2,909 reviews
Search JetBlue flights
Alaska AirlinesPriceFrom $257Free CancellationRating
7.9
12,091 reviews
Search Alaska Airlines flights

Traveling to a place near St. Louis?

Book flights to St. Louis if you plan to visit one of these locations
St. Charles
Chesterfield
Hermann
Fairview Heights
Florissant
Maryland Heights
O'Fallon
Collinsville
Alton
St. Peters
Wentzville
Fenton
Farmington
Clayton
Edwardsville
Festus
Eureka
Litchfield
Shrewsbury
Grafton

Why use momondo?

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

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 United States to St. Louis for you.

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

Yes. momondo enables you to select and highlight flights to St. Louis from United States with this policy.

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

momondo offers useful filters to help you find the right flight. Choose specific flight times, airports or even what payment method you prefer. We have numerous options to help you book your ideal flight from United States to St. Louis.

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

If you are simply researching potential flights to St. Louis, momondo offers a useful price alert feature which will track prices for flights to St. Louis from United States and alert you when they change.

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1 adult
Mon 4/20
Mon 4/27

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