46 CFR 10.203: Holding a TWIC and a Merchant Mariner Credential

Last reviewed: October 14, 2026

This section links the TWIC to the Merchant Mariner Credential (MMC). Not holding a valid TWIC is a basis for denying a credential application. Mariners must keep their MMC and TWIC and produce them when an authorized official requests them.

Applies toMariners who apply for or hold a Merchant Mariner Credential and a TWIC.

What it says

  1. Failure to obtain or hold a valid TWIC is a basis for denying an application for an original, renewal, new endorsement, duplicate, or raise of grade of a mariner's credential.

    46 CFR 10.203(a)“Failure to obtain or hold a valid TWIC serves as a basis for the denial of an application for an original, renewal, new endorsement, duplicate, or raise of grade of a mariner's credential”

  2. Failure to hold a valid TWIC may also be a basis for suspension and revocation under 46 U.S.C. 7702 and 7703.

    46 CFR 10.203(a)“may serve as a basis for suspension and revocation under 46 U.S.C. 7702 and 7703.”

  3. The mariner to whom an MMC was issued must retain it and, while it is valid, must produce it to verify qualifications when an authorized official identified in 33 CFR 101.515(d) asks for it.

    46 CFR 10.203(b)“An MMC must be retained by the mariner to whom it was issued and, while valid, must be produced to verify qualifications when requested by an authorized official as identified in 33 CFR 101.515(d).”

  4. Posting of the officer endorsement may be necessary as required in 46 U.S.C. 7110.

    46 CFR 10.203(b)“Posting of the officer endorsement may be necessary as required in 46 U.S.C. 7110.”

  5. The mariner to whom a TWIC was issued must retain it, and while valid it serves as the mariner's primary identification document.

    46 CFR 10.203(c)“a TWIC must be retained by the mariner to whom it was issued and, while valid, serves as the mariner's primary identification document.”

  6. The TWIC must be produced to verify identity when an authorized official identified in 33 CFR 101.515(d) requires it.

    46 CFR 10.203(c)“The TWIC must be produced to verify identity when required by an authorized official as identified in 33 CFR 101.515(d).”

Common questions

Can I get a mariner credential without a valid TWIC?

Failure to obtain or hold a valid TWIC is a basis for denying a credential application. This covers original, renewal, new endorsement, duplicate, and raise of grade applications.

“Failure to obtain or hold a valid TWIC serves as a basis for the denial of an application for an original, renewal, new endorsement, duplicate, or raise of grade of a mariner's credential”

Do I have to show my MMC when asked?

Yes. While the MMC is valid, the mariner must produce it to verify qualifications when an authorized official identified in 33 CFR 101.515(d) requests it.

“must be produced to verify qualifications when requested by an authorized official as identified in 33 CFR 101.515(d).”

Is my TWIC or my MMC my primary ID?

The TWIC serves as the mariner's primary identification document while it is valid, even though an MMC serves as certificates of identification.

“Although an MMC serves as certificates of identification, a TWIC must be retained by the mariner to whom it was issued”

The text of 46 CFR 10.203

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

Requirement to hold a TWIC and a Merchant Mariner Credential

(a) Failure to obtain or hold a valid TWIC serves as a basis for the denial of an application for an original, renewal, new endorsement, duplicate, or raise of grade of a mariner's credential and may serve as a basis for suspension and revocation under 46 U.S.C. 7702 and 7703.

(b) An MMC must be retained by the mariner to whom it was issued and, while valid, must be produced to verify qualifications when requested by an authorized official as identified in 33 CFR 101.515(d). Posting of the officer endorsement may be necessary as required in 46 U.S.C. 7110.

(c) Although an MMC serves as certificates of identification, a TWIC must be retained by the mariner to whom it was issued and, while valid, serves as the mariner's primary identification document. The TWIC must be produced to verify identity when required by an authorized official as identified in 33 CFR 101.515(d).

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.