Is there a limit to how many referral vouchers I can earn? January 04, 2019 19:17 Updated There is no limit to the amount of vouchers you can earn and apply to a future reservation. Related articles How does the referral program work? How will I receive my credit for a referring another customer? Can I earn a referral voucher for friends or family that are going on the same cruise with me? Why should I book with American Airlines Cruises? How can I transfer an existing cruise reservation?