There are no codes for onboard credits. DCL usually only has credits if you book another cruise onboard. Check out Dreams Unlimited b/c they offer specials with rebates if you book through them.
If you have a Disney Visa card and charge the whole cruise on it you get a $50.00 onboard credit. Also I believe if you are a Disney Club member you get the discount but you have to let them know that you are a member. Dreams Unlimited I believe offers an onboard credit if you book with them. And always check mousesavers.com because they are usually up to date. Good Luck.
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