Merchant Navy Ranks, Departments and Uniform Explained
Guide to merchant navy ranks, deck and engine departments, officer hierarchy, cadet roles, ETOs, ratings and what uniforms mean onboard.
Updated 2026-07-03
Guide overview
Merchant navy careers are structured around departments and certificates. Deck officers, marine engineers, ETOs and ratings have different responsibilities, training paths and promotion ladders.
The main departments
The deck department navigates the vessel, manages cargo operations, maintains safety equipment and handles bridge watchkeeping. The engine department operates propulsion, power generation, boilers, pumps, purifiers, compressors and auxiliary machinery.
The electro-technical department manages high-voltage systems, automation, sensors, alarms, communications and electrical maintenance. Ratings support deck, engine and hotel or service functions depending on vessel type.
Typical officer ladder
A deck officer route commonly moves from deck cadet to third officer, second officer, chief officer and master. An engine route commonly moves from trainee or junior engineer to fourth engineer, third engineer, second engineer and chief engineer.
Promotion is not automatic. Officers need sea time, assessments, exams, medical fitness, company appraisal and the relevant Certificate of Competency for the next rank.
- Deck: cadet, third officer, second officer, chief officer, master.
- Engine: trainee, fourth engineer, third engineer, second engineer, chief engineer.
- ETO: electro-technical officer, senior ETO or electrical superintendent route.
- Ratings: ordinary seaman, able seaman, oiler, fitter, motorman and specialist roles.
What uniform signals
Uniform helps identify department, rank and professional role, especially in ports, inspections and formal shipboard settings. It does not replace competence; certificates and watchkeeping responsibility matter more than appearance.
Uniform conventions vary by company and country. Candidates should treat online uniform searches as orientation, not as proof of rank or salary.
Useful next steps
Frequently asked questions
What is the highest rank in the merchant navy?
The highest shipboard deck rank is master or captain. The highest shipboard engine rank is chief engineer.
Is third officer a junior rank?
Yes. Third officer is usually the first qualified deck officer rank after cadetship, but it still carries legal watchkeeping responsibility.
Are merchant navy ranks the same in every country?
The broad ladder is similar because STCW is international, but exact titles, exams and certificate names differ by regulator and company.