A person may not use a vessel unless: It has a number issued on a certificate of number by the Department or the issuing authority in the state where the vessel is principally used; or The vessel is exempt from numbering pursuant to 33 CFR §173.13 as amended. Display. The number shall conform to the requirements of 33 CFR §174.23 as amended. The first part shall consist of the letters “MD”; The second part shall consist of not more than four Arabic numerals; The third part shall consist of not more than two letters; The parts shall be separated by a hyphen or an equivalent space, for example: MD-1-A, MD-1234-AA, MD 56 AA; and Letters “I”, “O” and “Q” may not be used in the suffix. Each number shall be displayed pursuant to 33 CFR §173.27 as amended. Painted on or permanently attached to each side of the forward half of the vessel except as allowed by §B(3), of this regulation, or required by §B(4), of this regulation; Plain vertical block characters not less than 3 inches high; Contrast with the color of the background and be distinctly visible and legible; and Read from left to right. A manufacturer or dealer, but not a broker, may apply to the Department for the issuance of certificates of number to be used for testing or demonstrating vessels. Vessel number shall end with the suffix “DL”. There can be no personal use of a vessel displaying a “DL” number. The number may be painted on or attached to removable plates that are temporarily but firmly attached to the side of the forward half of the vessel. On vessels so configured that a number on the hull or superstructure would not be easily visible, the number shall be painted on or attached to a backing plate that is attached to the forward half of the vessel so that the number is visible from each side of the vessel. Other numbers may not be carried on the forward half of the vessel. Except as provided in Regulation .04, a person may not use a vessel unless: It has a number issued on a certificate of number by the Department or the issuing authority in the state where the vessel is principally used; and The number is displayed as required by regulation §B, of this regulation. This regulation does not apply to a vessel for which a valid temporary certificate has been issued to its owner by the issuing authority in the state in which the vessel is principally used. Except as provided in 33 CFR §173.13 and 33 CFR §173.17 as amended, a person may not use a vessel unless it has on board: A valid certificate of number or temporary certificate for that vessel issued by the issuing authority in the state in which the vessel is principally used; or For the vessel described in §B of this regulation, a copy of the lease or rental agreement, signed by the owner or the owner's authorized representative and by the person leasing or renting the vessel, that contains at least: The vessel number that appears on the certificate of number; and The period of time for which the vessel is leased or rented. The certificate of number for a vessel less than 26 feet in length and leased or rented to another for the latter's noncommercial use of less than 7 days may be retained on shore by the vessel's owner or the owner's representative at the place from which the vessel departs or returns to the possession of the owner or the owner's representative. The numbering requirements do not apply to the following vessels: Exceptions noted in Natural Resources Article, §8-712(a)(1), Annotated Code of Maryland; A motor boat used solely for power boat racing which carries an official racing number issued by a recognized racing organization; Chesapeake Bay log sailing canoes which are registered with the Department, used exclusively for racing and which meet the specifications of the Chesapeake Bay Log Canoe Association as to construction and rig. These vessels shall display their names on each bow in letters not less than 3 inches high, and of a contrasting color to the background; and A vessel equipped with propulsion less than 10 horsepower used exclusively for direct transportation between a numbered vessel and the shore. Vessel must display the number of the numbered vessel followed by the suffix “I”. A vessel numbered in another state and temporarily using Maryland waters is deemed in compliance with the numbering system requirements of Maryland. When a vessel is moved to Maryland as the new state of principal use, a number awarded by another state shall be recognized as valid for 60 days before numbering issued by the Department is required. A person required to secure a certificate of number under 33 CFR §173.15 as amended shall submit to the Department an application for certificate of number and the required fee. The Department shall collect the information required by 33 CFR §187 as amended. Each certificate of number shall contain the information required by 33 CFR §174.19 as amended. A vessel issued a Maryland certificate of number must be titled in Maryland. Revocation. The Department may revoke a certificate of number issued under this chapter if the vessel has been altered in such a way that it is no longer eligible to be issued a certificate of number. Prior to revoking a certificate of number, the Department shall give the applicant notice of its intended action and an opportunity to appear at a hearing conducted in accordance with the contested case procedures set forth in State Government Article, Title 10, Subtitle 2, Annotated Code of Maryland, and COMAR 08.01.04. A person whose name appears as the owner of a vessel on a certificate of number shall notify the issuing authority within 15 days of: Any address change; The theft or recovery of the vessel; The loss or destruction of a valid certificate of number; The transfer of full or partial interest in the vessel; The destruction or abandonment of the vessel; Any email address change; or The alteration of the vessel in such a way that it is no longer eligible to be issued a certificate of number. The person whose name appears on a certificate of number as the owner of a vessel shall remove the number and validation sticker from the vessel when the: Vessel is documented by the Coast Guard; Certificate of number is invalid under Regulation .08 of this chapter; Vessel is no longer principally used in the state where the certificate was issued; or Certificate of number has been revoked. A certificate of number issued by the Department is invalid after the date when the: Vessel is documented or required to be documented under 46 CFR §67 as amended; Person whose name appears on the certificate of number as owner of the vessel, transfers all of his ownership of the vessel; or Vessel is destroyed or abandoned. A certificate of number issued by the Department is invalid if the: Application for the certificate of number contains a false or fraudulent statement; Fees for the issuance of the certificate of number are not paid; or Certificate of number has been revoked. A certificate of number is invalid 60 days after the day on which the vessel is no longer principally used in the state where the certificate was issued. The certificate of number is invalid when the person whose name appears on the certificate involuntarily loses ownership interest in the numbered vessel by legal process. The Department may supply true copies of applications for Certificates of Title or Certificates of Number to a vessel owner or his agent upon written application accompanied by a $10 fee for each true copy. The Department may supply a statement of the history record on a boat to a vessel owner or his agent upon written application accompanied by a $5 fee. Except as provided in §F of this regulation, in order to use Maryland waters, a vessel numbered by the State shall display two validation stickers issued in accordance with the provisions of Natural Resources Article, §8-712.1, Annotated Code of Maryland. The validation stickers expire December 31 of the year following issuance. The color of the validation sticker shall represent the year the validation stickers expire, with red for stickers that expire in 2012, followed by blue, international orange and green in rotation. If the validation stickers are defaced, lost, or destroyed, a sworn affidavit to that effect shall be filed within 15 days with the Department by the owner and application made for replacements. A service fee of $1 will be charged for the replacements. One validation sticker shall be affixed to the vessel: On each side of the vessel; and Within six inches of the vessel number. Exemptions. Temporary Registration Decals. A vessel is exempt from the requirement of displaying validation stickers if the temporary registration decals obtained from the licensed boat dealer are displayed and have not expired. Proof of Purchase. A vessel is exempt from the requirement of displaying validation stickers if: The individual who purchased the validation stickers is present on the vessel for which the stickers were issued; The individual who purchased the validation stickers is in possession of the proof of purchase issued by the Department; and The validation stickers were purchased within the previous 10 calendar days. The hull identification number is the permanent identification for any vessel titled under the provisions of Natural Resources Article, §8-715, Annotated Code of Maryland. The hull identification number shall be displayed on the vessel pursuant to 33 CFR §181.29 as amended. Carved, burned, stamped, embossed, molded, bonded, or otherwise permanently affixed so that alteration would be obvious; Primary hull identification number affixed to the starboard outboard side of the transom within two inches of the top of the transom, gunwale, or hull/deck joint, whichever is lowest; Duplicate hull identification number affixed in an unexposed location on the interior of the boat or beneath a fitting or item of hardware; and Characters must be no less than one-fourth of an inch high. Persons who build a vessel for their own use and are not engaged in the business of manufacturing boats for resale shall obtain from the Department a hull identification number for any vessel they build. Vessels built before November, 1972 are exempt from the requirements of this regulation. Natural Resources Article, §§8-704(c), 8-710.2, 8-712, and 8-712.1, Annotated Code of Maryland Effective date: August 10, 1974 (1:1 Md. R. 23) Regulations .02, .05C, D, .09A, .11 adopted effective June 25, 1975 (2:14 Md. R. 1015) Regulation .03 amended effective February 10, 1978 Regulation .06, .16, and .18 amended effective October 29, 1975 (2:24 Md. R. 1480) Chapter renumbered effective June 23, 1976 (3:13 Md. R. 721) Regulation .16 amended effective August 16, 1982 (9:16 Md. R. 1603) Chapter revised effective December 12, 2011 (38:25 Md. R. 1580) Regulation .05E adopted effective March 16, 2026 (53:5 Md. R. 243) Regulation .06 amended effective March 16, 2026 (53:5 Md. R. 243) Regulation .07 amended effective March 16, 2026 (53:5 Md. R. 243) Regulation .08 amended effective March 16, 2026 (53:5 Md. R. 243) Regulation .10A amended effective January 13, 2022 (49:1 Md. R. 13) Regulation .10E, F adopted effective January 13, 2022 (49:1 Md. R. 13)