The National Maritime Center has posted guidance on its website to help mariners submit a complete and accurate Merchant Mariner Credential (MMC) application package.

These guidance documents are intended to aid mariner applicants in properly completing the CG-719B application for MMC and the Evidence of Sea Service forms. To ensure mariners receive credentials within the NMC-stated processing goal of 30 days, proper submission of this documentation is essential.

A merchant mariner credential (MMC) (Coast Guard Form CG-4610) is a credential combining the elements of the merchant mariner's document (MMD), merchant mariner's license (license), and certificate of registry (COR)  as well as the STCW endorsement issued pursuant to the STCW Convention and STCW Code. MMDs, licenses, STCW endorsements and CORs are no longer issued as separate documents and all qualifications formerly entered on those separate documents appear in the form of an endorsement(s) on an MMC.

Two guides are currently available to assist mariner applicants in submitting application packages:

• How to fill out the CG-719B form, which can be found by clicking on the forms link, located on the NMC homepage at

• Sea service instructions, which can be found by clicking on the MMC Evaluation link, located on the NMC homepage at

Sea service is a measure of a mariner’s lifetime experience on boats, whether recreational, commercial, or military. It may be counted from the day a mariner turns age 16 and accumulates over his or her lifetime.

A day of sea service is any day that a mariner served upon a vessel in an assigned position in either the deck or engineering department of a vessel (not a passenger). The position may include duties such as: handling lines, being a lookout, steering the boat, and other navigational or propulsion functions. Sea service never expires and may be reused when applying for new endorsements. It is the mariner’s responsibility to keep copies of all sea service records.

For questions, visit the NMC website or contact the NMC Customer Service Center by e-mailing [email protected], by using the NMC online chat system, or by calling 1-888-IASKNMC (427-5662).