Merchant Mariner Credential
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The Merchant Mariner Credential (MMC) is the official document issued by the United States Coast Guard that authorizes a mariner to work aboard U.S.-flagged vessels. It replaces several older documents — including what was commonly known as a Seaman’s Book or Z-card — combining them into one streamlined, secure credential.
Whether you’re starting your maritime career or renewing your credentials, the MMC is essential for proving your qualifications, documenting your sea service, and securing legal employment at sea. With our support, you can apply quickly and confidently — without the usual delays or confusion.