46 CFR 15.535: Credential requirements for towing vessel officers

Last reviewed: October 14, 2026

This section sets the credential and route-proficiency requirements for the person directing a towing vessel. Towing vessels of at least 8 meters (26 feet) must be under a properly endorsed officer holding a completed Towing Officer Assessment Record. Towing vessels on the Lower Mississippi River face added requirements.

Applies toTowing vessels subject to subchapter M of this chapter, and certain towing vessels not subject to subchapter M that are at least 8 meters (26 feet) in length.

What it says

  1. The requirements in this section apply to a towing vessel subject to subchapter M of this chapter, and those vessels must also meet the requirements in § 15.515(c).

    46 CFR 15.535(a)“the requirements in this section apply to a towing vessel subject to subchapter M of this chapter. Vessels subject to this section must also meet the requirements in § 15.515(c).”

  2. A towing vessel at least 8 meters (26 feet) long that is not subject to subchapter M must meet paragraph (b) if it is a seagoing towing vessel of 300 gross tons or more subject to the provisions of subchapter I of this chapter.

    46 CFR 15.535(a)(1)“A seagoing towing vessel of 300 gross tons or more subject to the provisions of subchapter I of this chapter;”

  3. A towing vessel at least 8 meters (26 feet) long that is not subject to subchapter M must meet paragraph (b) if it is a public vessel as defined in 46 U.S.C. 2101.

    46 CFR 15.535(a)(3)“A public vessel as defined in 46 U.S.C. 2101.”

  4. Every towing vessel of at least 8 meters (26 feet) in length must be under the direction and control of a person holding an MMC endorsed as Master or Mate (Pilot) of Towing Vessels or as Master or Mate of vessels of greater than 200 gross register tons.

    46 CFR 15.535(b)“must be under the direction and control of a person holding a MMC endorsed as Master or Mate (Pilot) of Towing Vessels or as Master or Mate of vessels of greater than 200 gross register tons”

  5. That person must also hold a completed Towing Officer Assessment Record signed by a designated examiner indicating proficiency in operating towing vessels upon the appropriate route.

    46 CFR 15.535(b)“holding a completed Towing Officer Assessment Record signed by a designated examiner indicating that the officer is proficient in the operation of towing vessels upon the appropriate route.”

  6. In addition to paragraph (b), a towing vessel of any length operating in the pilotage waters of the Lower Mississippi River must be under the control of an officer with a First-Class Pilot's endorsement for that route, an MMC officer endorsement for the Western Rivers, or who meets paragraph (c)(1) or (2), as applicable.

    46 CFR 15.535(c)“any towing vessel operating in the pilotage waters of the Lower Mississippi River must be under the control of an officer who holds either a First-Class Pilot's endorsement for that route”

  7. To operate with tank barges or a tow carrying hazardous material regulated under subchapter N or O of this chapter, the officer in charge must have completed at least 12 round trips over the route as an observer, with at least 3 during hours of darkness.

    46 CFR 15.535(c)(1)“must have completed at least 12 round trips over this route as an observer, with at least 3 of those trips during hours of darkness”

  8. To operate without barges or with a tow of uninspected barges, the officer in charge must have completed at least 4 round trips over the route as an observer, with at least 1 during hours of darkness.

    46 CFR 15.535(c)(2)“must have completed at least 4 round trips over this route as an observer, with at least 1 of those trips during hours of darkness”

Common questions

What credential do I need to direct a towing vessel 8 meters or longer?

The person directing the vessel must hold an MMC endorsed as Master or Mate (Pilot) of Towing Vessels or as Master or Mate of vessels of greater than 200 gross register tons. That person must also hold a completed Towing Officer Assessment Record.

“must be under the direction and control of a person holding a MMC endorsed as Master or Mate (Pilot) of Towing Vessels or as Master or Mate of vessels of greater than 200 gross register tons”

How many observer round trips are needed on the Lower Mississippi River with tank barges?

The officer in charge must have completed at least 12 round trips as an observer, with at least 3 during hours of darkness. The officer must give the Coast Guard evidence on request that at least 1 of the 12 trips occurred within the last 5 years.

“must provide evidence to the Coast Guard upon request that at least 1 of the 12 round trips occurred within the last 5 years.”

Does this section apply to towing vessels not subject to subchapter M?

It can. A towing vessel at least 8 meters (26 feet) long that is not subject to subchapter M must meet paragraph (b) if it is one of the vessels listed in paragraph (a)(1) through (3).

“that is not subject to subchapter M must meet the requirements in paragraph (b) of this section if it is—”

The text of 46 CFR 15.535

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

Towing vessels

(a) Applicability. Except as provided in this paragraph (a), the requirements in this section apply to a towing vessel subject to subchapter M of this chapter. Vessels subject to this section must also meet the requirements in § 15.515(c). A towing vessel at least 8 meters (26 feet) in length, measured from end to end over the deck (excluding sheer), that is not subject to subchapter M must meet the requirements in paragraph (b) of this section if it is—

(1) A seagoing towing vessel of 300 gross tons or more subject to the provisions of subchapter I of this chapter;

(2) A vessel inspected under other subchapters of this chapter that may perform occasional towing; or

(3) A public vessel as defined in 46 U.S.C. 2101.

(b) Towing vessels 8 meters or more in length. Every towing vessel of at least 8 meters (26 feet) in length, measured from end to end over the deck (excluding sheer), must be under the direction and control of a person holding a MMC endorsed as Master or Mate (Pilot) of Towing Vessels or as Master or Mate of vessels of greater than 200 gross register tons, holding a completed Towing Officer Assessment Record signed by a designated examiner indicating that the officer is proficient in the operation of towing vessels upon the appropriate route.

(c) Towing Vessels of Any Length on the Lower Mississippi River. In addition to the requirements of paragraph (b) of this section, any towing vessel operating in the pilotage waters of the Lower Mississippi River must be under the control of an officer who holds either a First-Class Pilot's endorsement for that route, or MMC officer endorsement for the Western Rivers, or who meets the requirements of either paragraph (c)(1) or (2) of this section, as applicable.

(1) Moving tank or hazardous material barges. To operate a towing vessel with tank barges or a tow of barges carrying hazardous material regulated under subchapter N or O of this chapter, the officer in charge of the towing vessel must have completed at least 12 round trips over this route as an observer, with at least 3 of those trips during hours of darkness, and must provide evidence to the Coast Guard upon request that at least 1 of the 12 round trips occurred within the last 5 years.

(2) Moving uninspected barges or no barges. To operate a towing vessel without barges or a tow of uninspected barges, the officer in charge of the towing vessel must have completed at least 4 round trips over this route as an observer, with at least 1 of those trips during hours of darkness, and must provide evidence to the Coast Guard upon request that at least 1 of the 4 round trips occurred within the last 5 years.

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.