What is the cheapest airline to fly from St. Louis to Casper round-trip?

Cheapflights users have booked flights from St. Louis to Casper round-trip from $308. United Airlines is currently priced 34% below the average price you’ll pay for this route.

What is the cheapest month to book a flight from St. Louis to Casper?

Currently, January is the cheapest month in which you can book a flight from St. Louis to Casper (average of $348). Flying from St. Louis to Casper in June is currently the most expensive (average of $500). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

What is the cheapest day to fly from St. Louis to Casper?

Travelers seeking maximum savings on their St. Louis to Casper flight should consider departing on Saturday afternoons when fares are most often at their lowest. Tuesday afternoons flights should be avoided if possible as fares are typically the most expensive at this time.

In terms of precipitation, rainfall in Casper ranges from 0.5 - 2.0 inches per month. May is typically the wettest month, when rainfall can reach 2.0 in. January is typically the driest time to visit Casper when rainfall is around 0.5 in.

If weather is an important factor for your trip to Casper, use this chart to help with planning. For those seeking warmer temperatures, July is the ideal time of year to visit, when temperatures reach an average of 69.8 F. Travelers looking to avoid the cold should look outside of December, when temperatures are typically at their lowest (around 23.0 F).

What is the cheapest day to fly round-trip from St. Louis to Casper?

Flying to your destination on a Monday can be more expensive, but this shouldn’t discourage you from finding affordable options to get to Casper. Check prices with Cheapflights to find a great deal for your trip.

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

Due to multiple factors, expect to potentially pay more when booking in March. For low rates, September can be a great choice for travel to Casper. Flights to Casper from St. Louis in September are about $469 on average during September, but can be found for as low as $241.

What is the cheapest time of day to fly from STL to CPR?

It’s typically best to fly out from St. Louis to Casper at noon. Doing so could potentially save you 19% on the flight price compared to flying in the afternoon, which is usually more expensive.

Can I find deals for flights from St. Louis to Casper that include hotel bookings?

Yes. In addition to deals on St. Louis to Casper flights, Cheapflights offers vacation packages that include both flights and hotel.

How can I find direct flights from St. Louis to Casper?

After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from St. Louis to Casper.

Can I find deals for business class flights from St. Louis to Casper?

Yes. Cheapflights offers flight deals from St. Louis to Casper by cabin class. In addition to browsing deals, you can also filter by cabin class on the search results page after making a search.

$233+ Flights from St. Louis to Casper

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Cheap flight deals from St. Louis to Casper

Round-trip from	$308 (United Airlines)
One-way from	$233 (United Airlines)
Popular in	March
Cheapest in	September
Average price	$392

From Lambert-St Louis to Casper Natrona County

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One-way flight from Lambert-St Louis to Casper Natrona County

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Highest demand for flights based on searches. 31% potential increase in price ($218 potential increase over avg. RT price).

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Cheapest flight prices on average. 13% potential price decrease ($56 potential savings vs. average RT price).

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Average for round-trip flights in July 2025

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Find flight deals from St. Louis to Casper

Cheapest flights from St. Louis to Casper
Explore the most affordable flight options available from St. Louis to Casper. Find the lowest fares from popular airlines and budget airlines, with prices last updated on July 3, 2025.

Sat 8/165:15 amSTL - CPR

1 stop5h 44mUnited Airlines

Sat 8/235:30 amCPR - STL

1 stop6h 13mUnited Airlines

Deal found 7/1

$308

Best flights from St. Louis to Casper
Discover carefully curated flight deals from St. Louis to Casper that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated July 3, 2025.

Sat 8/165:15 amSTL - CPR

1 stop5h 44mUnited Airlines

Sat 8/235:30 amCPR - STL

1 stop6h 13mUnited Airlines

Deal found 7/1

$308

Last-minute flights from St. Louis to Casper
Discover last-minute flight deals from St. Louis to Casper. Data last updated July 3, 2025 and is based on user searches.

Tue 7/84:45 pmSTL - CPR

1 stop4h 41mUnited Airlines

Sat 7/123:16 pmCPR - STL

1 stop7h 43mUnited Airlines

Deal found 7/1

$449

Sat 8/165:15 amSTL - CPR

1 stop5h 44mUnited Airlines

Sat 8/235:30 amCPR - STL

1 stop6h 13mUnited Airlines

Deal found 7/1

$308

One-way flights from St. Louis to Casper
Search for one-way flight options from St. Louis to Casper. Find affordable one-way fares based on user searches. Data last updated July 3, 2025.

Mon 8/114:45 pmSTL - CPR

1 stop4h 41mUnited Airlines

Deal found 7/1

$233

Cheapflights Fare Finder

Use the filters below to find and compare flights from St. Louis to Casper that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

St. LouisCasper

STL - CPR

STLCPR

Lambert-St Louis

Sat 8/16

5:15 am-9:59 am

1 stop5h 44m

Casper Natrona County

Sat 8/23

5:30 am-12:43 pm

1 stop6h 13m

$308

St. LouisCasper

STL - CPR

STLCPR

Lambert-St Louis

Mon 8/11

4:45 pm-8:26 pm

1 stop4h 41m

$233

Flights are sorted by cheapest round-trip flights first.

Deals found on 7/1

Best time to book a flight from St. Louis to Casper

Have a flexible travel schedule? Discover the best time to fly to Casper from St. Louis with our price prediction graph.

Estimated round-trip price

Rates are based on past data. Find the cheapest month and day to book your flight based on your travel requirements, then search for cheap deals.

Reviews of airlines servicing Casper

See what other customers who have flown with United Airlines from St. Louis to Casper have to say. You can also see how each airline compares in terms of entertainment options, comfort, food, crew/service, and boarding process.

United Airlines

7.4

Good

8,845 reviews

Reviews

1 / 20

2.0

Mediocre

Deb,Jan 2025

MKE - ORD

It was terrible! So much to say, but in a nutshell we used vouchers from United because our last trip with them was awful with many mishaps and errors made. Unfortunately, this trip was even worse!

United Airlines

7.4

Good

8,845 reviews

United Airlines

7.4

Good

8,845 reviews

Reviews

1 / 20

2.0

Mediocre

Deb,Jan 2025

MKE - ORD

It was terrible! So much to say, but in a nutshell we used vouchers from United because our last trip with them was awful with many mishaps and errors made. Unfortunately, this trip was even worse!

Related info for your journey

What is the cheapest airline to fly from St. Louis to Casper round-trip?
Cheapflights users have booked flights from St. Louis to Casper round-trip from $308. United Airlines is currently priced 34% below the average price you’ll pay for this route.
Can I find deals for flights from St. Louis to Casper that include hotel bookings?
Yes. In addition to deals on St. Louis to Casper flights, Cheapflights offers vacation packages that include both flights and hotel.
How can I find direct flights from St. Louis to Casper?
After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from St. Louis to Casper.
Can I find deals for business class flights from St. Louis to Casper?
Yes. Cheapflights offers flight deals from St. Louis to Casper by cabin class. In addition to browsing deals, you can also filter by cabin class on the search results page after making a search.
What is the cheapest month to book a flight from St. Louis to Casper?
Currently, January is the cheapest month in which you can book a flight from St. Louis to Casper (average of $348). Flying from St. Louis to Casper in June is currently the most expensive (average of $500). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

See more FAQs

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Alternative routes for St. Louis to Casper

Top airline flying from St. Louis to Casper

Airline	Cheapest	Average	Flexibility	On-time
United Airlines	Cheapest$238	Average$353	FlexibilityNo cancel fee	On-time69%

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$233+ Cheap flights from St. Louis to Casper (STL - CPR)

This is the cheapest one-way flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 8/11. Fares are subject to change and may not be available on all flights or dates of travel.

Find cheap flights from St. Louis to Casper with Cheapflights

1. Tell us where you want to go

2. Select your favorite providers

3. Compare prices and book

Cheap flight deals from St. Louis to Casper

Round-trip from

One-way from

Popular in

Cheapest in

Average price

Find flight deals from St. Louis to Casper

Cheapest flights from St. Louis to CasperExplore the most affordable flight options available from St. Louis to Casper. Find the lowest fares from popular airlines and budget airlines, with prices last updated on July 3, 2025.

Explore the most affordable flight options available from St. Louis to Casper. Find the lowest fares from popular airlines and budget airlines, with prices last updated on July 3, 2025.

Cheapflights Fare Finder

Use the filters below to find and compare flights from St. Louis to Casper that are best for you.

Best time to book a flight from St. Louis to Casper

Have a flexible travel schedule? Discover the best time to fly to Casper from St. Louis with our price prediction graph.

Reviews of airlines servicing Casper

Get insights into the airlines that provide service to Casper. Read reviews, discover amenities, and learn about the overall travel experience offered by airlines. Use this information to make informed decisions when choosing an airline for your flight to Casper. Reviews last updated July 3, 2025.

See what other customers who have flown with United Airlines from St. Louis to Casper have to say. You can also see how each airline compares in terms of entertainment options, comfort, food, crew/service, and boarding process.

Related info for your journey

Find useful and relevant information for your journey from St. Louis to Casper. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.

What is the cheapest airline to fly from St. Louis to Casper round-trip?

Can I find deals for flights from St. Louis to Casper that include hotel bookings?

How can I find direct flights from St. Louis to Casper?

Can I find deals for business class flights from St. Louis to Casper?

What is the cheapest month to book a flight from St. Louis to Casper?

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Alternative routes for St. Louis to Casper

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Top airline flying from St. Louis to Casper

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Cheapest flights from St. Louis to Casper
Explore the most affordable flight options available from St. Louis to Casper. Find the lowest fares from popular airlines and budget airlines, with prices last updated on July 3, 2025.