46 CFR § 10.207 - Identification number.
---
identifier: "/us/cfr/t46/s10.207"
source: "ecfr"
legal_status: "authoritative_unofficial"
title: "46 CFR § 10.207 - Identification number."
title_number: 46
title_name: "Shipping"
section_number: "10.207"
section_name: "Identification number."
chapter_name: "COAST GUARD, DEPARTMENT OF HOMELAND SECURITY"
subchapter_number: "B"
subchapter_name: "MERCHANT MARINE OFFICERS AND SEAMEN"
part_number: "10"
part_name: "MERCHANT MARINER CREDENTIAL"
positive_law: false
currency: "2026-04-05"
last_updated: "2026-04-05"
format_version: "1.1.0"
generator: "[email protected]"
authority: "14 U.S.C. 503; 31 U.S.C. 9701; 46 U.S.C. 2101, 2103, 2104, 2110; 46 U.S.C. chapter 71; 46 U.S.C. chapter 73; 46 U.S.C. chapter 75; 46 U.S.C. 7701, 8903, 8904, and 70105; Executive Order 10173; DHS Delegation No. 00170.1, Revision No. 01.4."
regulatory_source: "USCG-2006-24371, 74 FR 11216, Mar. 16, 2009, unless otherwise noted."
cfr_part: "10"
---
# 10.207 Identification number.
For recordkeeping purposes only, a mariner's official MMC identification number is the individual's social security number. However, a unique serial number, called the mariner reference number, and not the social security number, will appear on the credential.
[USCG-2006-24371, 74 FR 11216, Mar. 16, 2009, as amended by USCG-2004-17914, 78 FR 77888, Dec. 24, 2013]