46 CFR 10.225: Requirements for original Merchant Mariner Credentials

Last reviewed: October 14, 2026

This section says who must apply for an original Merchant Mariner Credential (MMC) and what a complete application contains. It also sets out the oath every person receiving an original MMC must swear or affirm first.

Applies toApplicants for an original Merchant Mariner Credential (MMC).

What it says

  1. An applicant must apply as an original if the MMC sought is the first credential issued to the applicant.

    46 CFR 10.225(a)“An applicant must apply as an original if the MMC sought is—”

  2. An applicant must also apply as an original if the previous credential expired beyond the grace period and the applicant holds no Document of Continuity under § 10.227(g) of this part or equivalent unexpired continuity endorsement on a license or MMD.

    46 CFR 10.225(a)(2)“The first credential issued to applicants after their previous credential has expired beyond the grace period and they do not hold a Document of Continuity under § 10.227(g) of this part”

  3. An applicant must apply as an original if the MMC sought is the first credential issued after the previous credential was revoked pursuant to § 10.235 of this part.

    46 CFR 10.225(a)(3)“The first credential issued to applicants after their previous credential was revoked pursuant to § 10.235 of this part.”

  4. A complete application must contain a completed, signed application and proof that the mariner either holds a valid TWIC or has applied for a TWIC, except as otherwise noted in § 10.227(i) of this subpart.

    46 CFR 10.225(b)(2)“Proof that the mariner either holds a valid TWIC or has applied for a TWIC.”

  5. The application must include all supplementary materials required to show that the mariner meets the mandatory requirements for all endorsements sought. Part 11 of this subchapter covers officer endorsements, part 12 covers rating endorsements, and part 13 covers tank vessel endorsements.

    46 CFR 10.225(b)(3)“All supplementary materials required to show that the mariner meets the mandatory requirements for all endorsements sought as follows:”

  6. The application must include the appropriate fee as set forth in § 10.219 of this part.

    46 CFR 10.225(b)(4)“The appropriate fee as set forth in § 10.219 of this part.”

  7. The application must include evidence of having passed a chemical test for dangerous drugs or of qualifying for an exemption from testing in § 16.220 of this subchapter.

    46 CFR 10.225(b)(5)“Evidence of having passed a chemical test for dangerous drugs or of qualifying for an exemption from testing in § 16.220 of this subchapter.”

  8. Every person who receives an original MMC must first swear or affirm the oath, which remains binding for later MMCs and added endorsements unless specifically renounced in writing.

    46 CFR 10.225(c)“This affirmation remains binding for any subsequently issued MMC and endorsements added to the MMC, unless specifically renounced in writing.”

Common questions

When do I have to apply for an original MMC?

You must apply as an original if the MMC is your first credential. You must also do so if your previous credential was revoked pursuant to § 10.235 of this part.

“The first credential issued to applicants after their previous credential was revoked pursuant to § 10.235 of this part.”

Do I need a TWIC to apply for an original MMC?

You need proof that you either hold a valid TWIC or have applied for a TWIC.

“Proof that the mariner either holds a valid TWIC or has applied for a TWIC.”

Is a drug test required for an original MMC application?

The application must contain evidence of having passed a chemical test for dangerous drugs or of qualifying for an exemption from testing in § 16.220 of this subchapter.

“Evidence of having passed a chemical test for dangerous drugs or of qualifying for an exemption from testing in § 16.220 of this subchapter.”

The text of 46 CFR 10.225

Electronic Code of Federal Regulations (eCFR), current as of April 16, 2026 · Read it on eCFR

Requirements for original Merchant Mariner Credentials

(a) An applicant must apply as an original if the MMC sought is—

(1) The first credential issued to the applicant;

(2) The first credential issued to applicants after their previous credential has expired beyond the grace period and they do not hold a Document of Continuity under § 10.227(g) of this part or an equivalent unexpired continuity endorsement on their license or MMD; or

(3) The first credential issued to applicants after their previous credential was revoked pursuant to § 10.235 of this part.

(b) A complete application for an original MMC must contain the following, except as otherwise noted in § 10.227(i) of this subpart:

(1) A completed, signed application.

(2) Proof that the mariner either holds a valid TWIC or has applied for a TWIC.

(3) All supplementary materials required to show that the mariner meets the mandatory requirements for all endorsements sought as follows:

(i) The mandatory requirements for officer endorsements are contained in part 11 of this subchapter.

(ii) The mandatory requirements for rating endorsements are contained in part 12 of this subchapter.

(iii) The mandatory requirements for tank vessel endorsements are contained in part 13 of this subchapter.

(iv) The mandatory requirements for STCW endorsements are contained in parts 11, 12, and 13 of this subchapter.

(4) The appropriate fee as set forth in § 10.219 of this part.

(5) Evidence of having passed a chemical test for dangerous drugs or of qualifying for an exemption from testing in § 16.220 of this subchapter.

(6) Where sea service is required, documentary evidence in accordance with § 10.232 of this part.

(7) Proof, documented on CG-719-K or CG-719-K/E, as appropriate, that the applicant passed all applicable vision, hearing, medical, and/or physical exams as required by subpart C of this part or a valid medical certificate issued by the Coast Guard.

(8) Consent to a Coast Guard check of the NDR for offenses described in section 205(a)(3)(A) or (B) of the National Driver Register Act of 1982, as amended.

(9) The oath as required in paragraph (c) of this section.

(c) Oath. Every person who receives an original MMC must first solemnly swear or affirm, that they will faithfully and honestly, according to their best skill and judgment, without concealment or reservation, perform all the duties required by law and obey all lawful orders of superior officers. This affirmation remains binding for any subsequently issued MMC and endorsements added to the MMC, unless specifically renounced in writing.

Sections it refers to

The plain-English explanation on this page was written with AI from the regulation text above and checked automatically before publishing: every quote appears in the text, every number comes from it, and a second model confirmed each statement adds nothing the text doesn't say. Regulation text current as of April 16, 2026. The regulation text governs. RegKnot is not affiliated with the U.S. Coast Guard.