To save on the cost of your flight from Illinois to Rapid City Regional, book at least 57 days before your planned departure. Booking around this time can save you about 92% on the cost of this flight compared to booking a flight leaving this week. We have found prices from $249 if you need a flight within two weeks. For flights within the next 72 hours, you can find tickets from as low as $387.
The best pricing can be found in the month of September. Prices to Rapid City Regional from Illinois average $256. You can even find prices in September for less than $256, as users have found deals to Rapid City Regional from as low as $153. The month of March appears to be one of the more expensive times to travel to Rapid City Regional from Illinois. Flying in the targeted month can save you up to 75%.