Norwegian said any guest that has made a booking by March 31, 2017 will have the option of prepaying their service charges at the current rate if done prior to sail date.
The gratuity amounts are automatically added to a guest's shipboard account. Guests can adjust the rate upward or downward, but only by contacting guest relations at Norwegian after they have returned from their cruise. The Gratuity amount on Norwegian is Monitory and guests do not have a choice to change it based upon service they receive. On board it is referred to as a Service Charge.