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Cheap flights from Casper to St. Louis from $318

This is the cheapest round-trip flight price found by a momondo user in the last 72 hours by searching for a flight from Casper to St. Louis departing on 5/29. 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 Casper to St. Louis

Cheap round-trip flights

Enter your travel dates to find the best prices.
United Airlines Logo
3:15 pm - 11:57 pm
CPR
-
STL
7h 42m
1 stop
United Airlines Logo
5:10 am - 8:51 am
STL
-
CPR
4h 41m
1 stop
$318United Airlines
Fri, May 29 - Mon, Jun 1
United Airlines Logo
1:21 pm - 8:54 pm
CPR
-
STL
6h 33m
1 stop
United Airlines Logo
4:30 pm - 8:26 pm
STL
-
CPR
4h 56m
1 stop
$328United Airlines
Fri, Apr 17 - Tue, Apr 21
United Airlines Logo
3:14 pm - 8:54 pm
CPR
-
STL
4h 40m
1 stop
United Airlines Logo
10:00 am - 6:59 pm
STL
-
CPR
9h 59m
2 stops
$334United Airlines
Fri, Apr 17 - Tue, Apr 21
United Airlines Logo
3:14 pm - 8:43 pm
CPR
-
STL
4h 29m
1 stop
United Airlines Logo
4:15 pm - 10:10 pm
STL
-
CPR
6h 55m
1 stop
$398United Airlines
Tue, May 5 - Sat, May 9
United Airlines Logo
11:23 am - 8:43 pm
CPR
-
STL
8h 20m
1 stop
United Airlines Logo
10:25 am - 10:10 pm
STL
-
CPR
12h 45m
2 stops
$404United Airlines
Tue, May 5 - Sat, May 9
United Airlines Logo
11:23 am - 10:56 pm
CPR
-
STL
10h 33m
2 stops
United Airlines Logo
10:25 am - 8:17 pm
STL
-
CPR
10h 52m
2 stops
$409United Airlines
Tue, May 5 - Sat, May 9
United Airlines Logo
11:21 am - 9:16 pm
CPR
-
STL
8h 55m
2 stops
United Airlines Logo
5:10 am - 8:51 am
STL
-
CPR
4h 41m
1 stop
$414United Airlines
Fri, May 29 - Mon, Jun 1
United Airlines Logo
11:22 am - 9:13 pm
CPR
-
STL
8h 51m
2 stops
United Airlines Logo
6:30 am - 2:39 pm
STL
-
CPR
9h 09m
2 stops
$419United Airlines
Sat, Apr 18 - Wed, Apr 22
United Airlines Logo
11:23 am - 8:43 pm
CPR
-
STL
8h 20m
1 stop
United Airlines Logo
8:46 am - 5:32 pm
STL
-
CPR
9h 46m
1 stop
$429United Airlines
Tue, May 5 - Sat, May 9
United Airlines Logo
11:23 am - 10:56 pm
CPR
-
STL
10h 33m
2 stops
United Airlines Logo
7:45 am - 6:57 pm
STL
-
CPR
12h 12m
2 stops
$439United Airlines
Tue, May 5 - Sat, May 9

United Airlines flights from Casper to St. Louis

Our best United Airlines deals on Casper to St. Louis flight tickets
United Airlines
May 29
CPR3:15 pmCasper Natrona County
7h 42m
1 stop
STL11:57 pmLambert-St Louis
Jun 1
STL5:10 amLambert-St Louis
4h 41m
1 stop
CPR8:51 amCasper Natrona County
$318
United Airlines
Apr 17
CPR1:21 pmCasper Natrona County
6h 33m
1 stop
STL8:54 pmLambert-St Louis
Apr 21
STL4:30 pmLambert-St Louis
4h 56m
1 stop
CPR8:26 pmCasper Natrona County
$328
United Airlines
Apr 17
CPR3:14 pmCasper Natrona County
4h 40m
1 stop
STL8:54 pmLambert-St Louis
Apr 21
STL10:00 amLambert-St Louis
9h 59m
2 stops
CPR6:59 pmCasper Natrona County
$334

momondo Fare Finder

 
Customize your flight search to find flights from Casper 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 April 6, 2026.
Use the filters below to find and compare flights from Casper to St. Louis that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

Cheapest round-trip

CasperSt. Louis

CPR - STL

CPRSTL

Casper Natrona County

Fri 5/29

3:15 pm-11:57 pm

1 stop7h 42m

Lambert-St Louis

Mon 6/1

5:10 am-8:51 am

1 stop4h 41m

$318

CasperSt. Louis

CPR - STL

CPRSTL

Casper Natrona County

Fri 4/17

1:21 pm-8:54 pm

1 stop6h 33m

Lambert-St Louis

Tue 4/21

4:30 pm-8:26 pm

1 stop4h 56m

$328

CasperSt. Louis

CPR - STL

CPRSTL

Casper Natrona County

Fri 4/17

3:14 pm-8:54 pm

1 stop4h 40m

Lambert-St Louis

Tue 4/21

10:00 am-6:59 pm

2 stops9h 59m

$334
Quickest round-trip

CasperSt. Louis

CPR - STL

CPRSTL

Casper Natrona County

Tue 5/5

3:14 pm-8:43 pm

1 stop4h 29m

Lambert-St Louis

Sat 5/9

4:15 pm-10:10 pm

1 stop6h 55m

$398

CasperSt. Louis

CPR - STL

CPRSTL

Casper Natrona County

Tue 5/5

11:23 am-8:43 pm

1 stop8h 20m

Lambert-St Louis

Sat 5/9

10:25 am-10:10 pm

2 stops12h 45m

$404

CasperSt. Louis

CPR - STL

CPRSTL

Casper Natrona County

Tue 5/5

11:23 am-10:56 pm

2 stops10h 33m

Lambert-St Louis

Sat 5/9

10:25 am-8:17 pm

2 stops10h 52m

$409

CasperSt. Louis

CPR - STL

CPRSTL

Casper Natrona County

Fri 5/29

11:21 am-9:16 pm

2 stops8h 55m

Lambert-St Louis

Mon 6/1

5:10 am-8:51 am

1 stop4h 41m

$414

CasperSt. Louis

CPR - STL

CPRSTL

Casper Natrona County

Sat 4/18

11:22 am-9:13 pm

2 stops8h 51m

Lambert-St Louis

Wed 4/22

6:30 am-2:39 pm

2 stops9h 09m

$419

CasperSt. Louis

CPR - STL

CPRSTL

Casper Natrona County

Tue 5/5

11:23 am-8:43 pm

1 stop8h 20m

Lambert-St Louis

Sat 5/9

8:46 am-5:32 pm

1 stop9h 46m

$429

CasperSt. Louis

CPR - STL

CPRSTL

Casper Natrona County

Tue 5/5

11:23 am-10:56 pm

2 stops10h 33m

Lambert-St Louis

Sat 5/9

7:45 am-6:57 pm

2 stops12h 12m

$439

Flights are sorted by cheapest round-trip flights first.

Sorted by cheapest first

When to book flights from Casper to St. Louis

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

Cheap Casper to St. Louis (CPR to STL) flight deals and tips

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

Fastest flight time

4h 40m

Direct flights

None
The fastest flight from Casper to St. Louis takes 4h 40m
There are no direct flights from Casper to St. Louis. There are no popular flight routes from Casper to St. Louis.
Search flight deals

Frequently asked questions about flying from Casper to St. Louis

  • How far is Casper Natrona County to Lambert-St Louis by plane?

    There are 891.0 mi between Casper Natrona County and Lambert-St Louis. 4h 40m is a normal flight duration for this route.

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

    Prices for flights from Casper Natrona County Airport to Lambert-St Louis Airport are updated daily.

  • How many operators does momondo search for flights from Casper Natrona County Airport to Lambert-St Louis Airport?

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

    The minimum age for a child to fly alone is five, but airlines offering an unaccompanied minor (UNMR) service may have their age restrictions, such as regulations concerning flight duration, timing, and layovers. It is recommended that you verify with the airline you are booking with for travel from Casper Natrona County Airport to Lambert-St Louis Airport.

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

    The travel and health documents you'll need for your trip to Lambert-St Louis Airport may differ based on your itinerary and personal situation. Typically, you should have several documents on hand, such as a national ID card or driver's license and a passport that is valid for six months after your intended arrival at Lambert-St Louis Airport. It is always advisable to seek advice from your airline or a trusted third party, such as IATA.

  • What is the most popular airline from Casper to St. Louis?

Best airlines flying from Casper to St. Louis

Compare and see reviews for airlines that fly from Casper to St. Louis with momondo
Airline
Rating
Free Cancellation
Price
United AirlinesPriceFrom $238Free CancellationRating
7.4
9,545 reviews
Search United Airlines flights

Frequently asked questions about flying from Casper to St. Louis

  • How do I get Price Alerts for flights from Casper to St. Louis?

    You can take advantage of momondo’s Price Alerts by first searching for your flights to Casper from St. Louis. Flight offers will be shown to you in real-time. From there you can create a Price Alert by using our on-site widget.

  • How can I save money on flights from Casper to St. Louis with momondo?

    Leverage our AI within our “Price Forecast” tool, which predicts if it’s better to book now or wait until prices decrease. You can strategically pick the best days to fly and save money on your trip by using our “Price Calendar” tool. “Explore” shows an overview of how much it costs to fly to anywhere from a selected city or airport. Our “Discover” content is a great option for travel inspiration and money-saving tips, while “Price Alerts” will update you when prices change, so you can book when fares are right.

  • How does momondo find its flight prices?

    We show prices from over 700+ competitors with a single click. With options from airlines and OTAs from across our 30 international markets, we are able to show you a diverse range of deals to create your adventure.

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
Maryland Heights
O'Fallon
Florissant
St. Peters
Collinsville
Alton
Wentzville
Fenton
Farmington
Clayton
Festus
Eureka
Edwardsville
Litchfield
Shrewsbury
Grafton

Why use momondo?

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

momondo compares prices from hundreds of airlines and agents so you can find and book the best deal on flights from Casper to St. Louis. Millions of users trust and use momondo every year so you are in good hands.

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

All flight searches from Casper to St. Louis on momondo can be filtered to show those which offer flexible booking policies.

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

I’m not ready to book a flight from Casper 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 Casper and alert you when they change.

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