Yes, most hotel room reservations are fully refundable if you cancel prior to the accommodation's cancellation deadline, which in most cases is within 24 or 48 hours of your arrival date. If you have a non-refundable reservation, you may still be able to cancel and receive a refund within a 24-hour period of your booking. Plug in your dates, click on "Search", then you can use the "fully refundable" filter to view the best deals near Ko Similan National Park.