33 CFR § 187.9 - What is a vessel identifier and how is one assigned?

---
identifier: "/us/cfr/t33/s187.9"
source: "ecfr"
legal_status: "authoritative_unofficial"
title: "33 CFR § 187.9 - What is a vessel identifier and how is one assigned?"
title_number: 33
title_name: "Navigation and Navigable Waters"
section_number: "187.9"
section_name: "What is a vessel identifier and how is one assigned?"
chapter_name: "COAST GUARD, DEPARTMENT OF HOMELAND SECURITY"
subchapter_number: "S"
subchapter_name: "BOATING SAFETY"
part_number: "187"
part_name: "VESSEL IDENTIFICATION SYSTEM"
positive_law: false
currency: "2026-03-24"
last_updated: "2026-03-24"
format_version: "1.1.0"
generator: "[email protected]"
authority: "46 U.S.C. 2103, 12501, 31322; DHS Delegation No. 00170.1, Revision No. 01.2, paragraph (II)(92)."
regulatory_source: "USCG-1999-6420, 66 FR 15630, Mar. 20, 2001, unless otherwise noted."
cfr_part: "187"
---


# 187.9 What is a vessel identifier and how is one assigned?

(a) The vessel identifier for a vessel having a valid HIN is the HIN.

(b) If a vessel does not have a valid HIN, a vessel identifier is assigned under the following table:

Table **187.9(b)**—Vessel Identifier Assignments

| If the vessel is: | And does not have a valid HIN: | Then the vessel identifier is: |
| --- | --- | --- |
| (1) Documented |  | The official number assigned by the Coast Guard under 46 CFR part 67. |
| (2) Documented | And is transferred to a new owner | The HIN assigned by the Coast Guard. |
| (3) Undocumented | And must be numbered under 33 CFR parts 173 and 174 | The number issued on a certificate of number by the issuing authority of the State of principal operation, provided the number will not be used in the future to identify a different vessel. |
| (4) Undocumented | And is transferred to a new owner | The HIN assigned by the issuing authority of the State of principal operation. |
| (5) Undocumented | And the vessel is required to be numbered or titled in a new State of principal operation | The HIN assigned by the issuing authority of the State of principal operation. |