$175 Cheap Flights from Rapid City (RAP) to St. Louis (STL)

View $175 flight on Wed, Aug 20, 2025Opens in a new window

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Find available prices by choosing your travel dates.

Cheap Flights from Rapid City to St. Louis (RAP-STL)

Prices were available within the past 7 days and start at $175 for one-way flights and $249 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

American Airlines
Wed, Aug 20 - Wed, Aug 27
RAP
Rapid City
STL
St. Louis
$249 Roundtrip, just found
$249
Roundtrip
just found
Select American Airlines flight, departing Wed, Aug 20 from Rapid City to St. Louis, returning Wed, Aug 27, priced at $249 just found
Delta
Wed, Aug 20 - Wed, Aug 27
RAP
Rapid City
STL
St. Louis
$249 Roundtrip, just found
$249
Roundtrip
just found
Select Delta flight, departing Wed, Aug 20 from Rapid City to St. Louis, returning Wed, Aug 27, priced at $249 just found
United
Wed, Aug 20 - Wed, Aug 27
RAP
Rapid City
STL
St. Louis
$249 Roundtrip, just found
$249
Roundtrip
just found
Select United flight, departing Wed, Aug 20 from Rapid City to St. Louis, returning Wed, Aug 27, priced at $249 just found
Delta
Thu, May 8 - Tue, May 27
RAP
Rapid City
STL
St. Louis
$254 Roundtrip, found 5 days ago
$254
Roundtrip
found 5 days ago
Select Delta flight, departing Thu, May 8 from Rapid City to St. Louis, returning Tue, May 27, priced at $254 found 5 days ago
United
Wed, Aug 20 - Wed, Aug 27
RAP
Rapid City
STL
St. Louis
$254 Roundtrip, just found
$254
Roundtrip
just found
Select United flight, departing Wed, Aug 20 from Rapid City to St. Louis, returning Wed, Aug 27, priced at $254 just found
Delta
Wed, May 7 - Sat, May 10
RAP
Rapid City
STL
St. Louis
$259 Roundtrip, found 2 days ago
$259
Roundtrip
found 2 days ago
Select Delta flight, departing Wed, May 7 from Rapid City to St. Louis, returning Sat, May 10, priced at $259 found 2 days ago
United
Tue, Jun 17 - Sat, Jun 21
RAP
Rapid City
STL
St. Louis
$267 Roundtrip, found 10 hours ago
$267
Roundtrip
found 10 hours ago
Select United flight, departing Tue, Jun 17 from Rapid City to St. Louis, returning Sat, Jun 21, priced at $267 found 10 hours ago
American Airlines
Wed, Aug 20 - Wed, Aug 27
RAP
Rapid City
STL
St. Louis
$269 Roundtrip, just found
$269
Roundtrip
just found
Select American Airlines flight, departing Wed, Aug 20 from Rapid City to St. Louis, returning Wed, Aug 27, priced at $269 just found
Delta
Thu, Jul 31 - Sat, Aug 9
RAP
Rapid City
STL
St. Louis
$279 Roundtrip, found 3 days ago
$279
Roundtrip
found 3 days ago
Select Delta flight, departing Thu, Jul 31 from Rapid City to St. Louis, returning Sat, Aug 9, priced at $279 found 3 days ago
Delta
Sat, May 3 - Wed, May 7
RAP
Rapid City
STL
St. Louis
$284 Roundtrip, found 3 days ago
$284
Roundtrip
found 3 days ago
Select Delta flight, departing Sat, May 3 from Rapid City to St. Louis, returning Wed, May 7, priced at $284 found 3 days ago

Frequently asked questions

How much does a flight from Rapid City Regional Airport (RAP) to Lambert-St. Louis Intl. Airport (STL) cost?
Discover the latest flight deals from RAP to STL by entering your preferred travel dates and searching on Expedia. Easily compare prices by departure date if you have flexibility with your schedule and use handy filters to explore prices for your preferred journey. As a member of One Key™, our free loyalty program, you can use Price Tracking to watch fares and receive notifications if prices go up or down.
What is the cheapest month to fly from RAP to STL?
The cheapest flights from RAP to STL are usually during off-peak season, when demand is lower. To save money, avoid flying during public holidays, school breaks and major local events.
What is the cheapest airline that flies from RAP to STL?
Use the filter tool on Expedia to compare airlines and find the cheapest carrier that’ll take you from RAP to STL. Sort your results by “Price (lowest to highest)” to snap up a great deal.
How many flights per day from Rapid City Regional Airport (RAP) to Lambert-St. Louis Intl. Airport (STL)?
There aren’t any daily direct flights from Rapid City Regional Airport (RAP) to Lambert-St. Louis Intl. Airport (STL). But you can opt for flights with layovers. Filter your search results on Expedia to include one or two stops, and you’ll be on your way in no time at all.
What day of the week has the most flights from RAP to STL?
You’ll usually find Tuesday the quietest day for flights, while Fridays tend to be the busiest.* However this can change from season to season and during public holidays or peak travel times.*Busiest/quietest day to travel is based on Expedia flight demand through January to December 2024.
What is the best time to fly from Rapid City Regional Airport (RAP) to Lambert-St. Louis Intl. Airport (STL)?
To avoid potential delays on the Rapid City Regional Airport (RAP) to Lambert-St. Louis Intl. Airport (STL) route, fly before 3 PM. Departures after this time are 22% more likely to be canceled.**Most reliable time of the day and month to travel recommendation is based on January through August 2024 flight status data sourced from OAG’s global flight data platform.
Is it cheaper to buy a plane ticket from Rapid City Regional Airport (RAP) to Lambert-St. Louis Intl. Airport (STL) last-minute?
Last-minute fares from RAP to STL are typically more expensive. To lock in the best rates, start looking for flights well in advance. That being said, if you’re flexible with your travel dates, you may score a cheap ticket right before your journey.
Is it cheaper to book a RAP to STL flight and hotel package?
Booking a RAP to STL flight and hotel package is generally cheaper than booking separately. With Expedia, you can enjoy the convenience of organizing your trip in one place. Pick from our extensive range of stays and then add car rentals, activities and flights to your booking. Bundle it all together, and you could save hundreds of dollars.
Can I cancel or change the date of my flight from Rapid City Regional Airport (RAP) to Lambert-St. Louis Intl. Airport (STL)?
If you reserved your RAP to STL flight within the last 24 hours, you may be able to cancel or modify it without fees. Depending on the airline and the type of ticket you purchased, additional charges may apply for changes beyond that time. Airline policies and contact information can be found in your itinerary or confirmation email. Or, visit our Customer Service portal for more information.
*Available to One Key members.