No, Marriott Bonvoy points purchases are non-refundable once the transaction is complete. According to Marriott's official policy, points that are purchased or gifted through the online portal are final. This is because the points are deposited into your account almost immediately (usually within 72 hours), and the system does not allow for a "reversal" of the sale. However, if you used points to book a hotel room and then cancelled within the hotel's specified cancellation window, those specific points would be returned to your account. But for the actual cash-for-points transaction, once you hit "purchase," the money is gone, and the points are yours to keep for future redemptions.