Deck Certificate Guide

Chief Mate Yachts (less than 3,000 GT): the exact requirements

The captain's deputy on commercial yachts of less than 3,000 GT, issued under STCW Regulation II/2. Chief Mate is qualification-gated, not sea-time-gated: no additional sea time is required beyond OOW. Every requirement below comes from section 3.4 of MSN 1858 (M+F) Amendment 2.

Updated July 2026 · Source: MSN 1858 (M+F) Amendment 2, section 3.4

What the Chief Mate CoC lets you do

The Chief Mate (Yachts, less than 3,000 GT) Certificate of Competency qualifies you to serve as the captain's deputy: you run the deck department, own the vessel's safety and maintenance planning, and take full navigational responsibility when the captain is off the bridge. It is issued under STCW Regulation II/2 and its requirements are set out in section 3.4 of MSN 1858 (M+F) Amendment 2.

Exact requirements

  1. OOW baseline: hold or meet all the requirements for the OOW Yachts (less than 3,000 GT) CoC.
  2. Sea service: no additional sea time is required beyond the OOW requirements. Chief Mate can be applied for together with OOW (per s6.10 of the notice).
  3. Ocean qualification: RYA Yachtmaster Ocean, or IYT Master of Yachts Unlimited.
  4. Academic modules: nine academic modules completed at an MCA-approved nautical college.
  5. Advanced Fire Fighting: first required at this level (it is not an OOW requirement).
  6. Medical First Aid: first required at this level.
  7. ECDIS: ECDIS certification.
  8. HELM Management: the management-level HELM course.

For the full ancillary certificate tables in section 6, fees and application details, check the current notice on gov.uk.

"Onboard yacht service: Is the time spent signed on a yacht, irrespective of the vessel's activity. Seagoing service: Is the time spent at sea, which may include time at anchor."

MSN 1858 (M+F) Amendment 2, section 5.2 definitions · Read the full notice on gov.uk

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Source documents

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Related: Deck career overview · Yacht Rating Certificate · OOW Yachts (less than 3,000 GT) · Master Yachts (less than 500 GT) · Master Yachts (less than 3,000 GT) · Chief Mate Yachts Unlimited · Master Yachts Unlimited