To save up to 11% on this flight, we recommend booking at least 41 days prior to travel. The price may fluctuate and will likely increase closer to your departure date. Users on Cheapflights have found tickets from Rapid City to Puerto Rico from $380 1-2 weeks out and tickets from $415 for flights departing within the next 72 hours.
Flights from Rapid City to Puerto Rico lean towards being more expensive in December. Prices are generally better when you fly from Rapid City to Puerto Rico in September, with the cheapest ticket starting at $194.