When do I need to complete the redemption form to qualify for my onboard credit? March 21, 2019 17:50 Updated To qualify for your onboard credit, you must fill out the redemption form no later than 21 days prior to departure. Related articles What is my "up to $750 Onboard Credit" amount? How do I choose between Onboard Credit or Amazon gift card? How can I get a copy of my reservation details (invoice)? How do I access my Cruises Only reservation? Should I purchase a beverage package from the cruise line?