If you’re thinking about getting your third mate endorsement, then you’ve put in your time on big vessels and are ready to leap to the next level of your marine career. A third mate is an officer of a ship’s deck department and is responsible for supervising many high-priority operations. It’s one of the most vital roles on any vessel and a prestigious position to achieve.

Throughout this article, we’ll cover everything you’ll want to know about the Third Mate:

If you’re looking into third mate license requirements and how to become a deck officer, you probably want more information before you jump into your third mate training. We gathered information to help you through the process and answer some common questions. We’ll go over:

  1. The Work of a Third Mate
  2. How to Become a Third Mate
  3. The Salary of a Third Mate
  4. Third Mate Training Programs

Becoming a third mate offers an excellent opportunity for those who want to advance their careers on the seas. Let’s begin by examining what type of work you do as a third mate.

What Is the Work of a Third Mate?

Specific day-to-day duties and responsibilities for a third mate depend on the type of ship you work aboard, but generally third mates are responsible for watchstanding, supervision of deck operations and safety.

As an Officer in Charge of a Navigational Watch, they command the bridge during normal activities. Watchstanding and supervision duties fit into two broad categories — at-sea watch and in-port watch:

  • At-Sea Watch – When underway, the third mate is in charge of navigation and vessel traffic management. They use the latest technology to plot safe courses and are familiar with traditional navigation practices like chart plotting and celestial navigation. Also, third mates often act as the helmsman — steering the ship while monitoring navigational aids.
  • In-Port Watch – When on anchor or in port, deck officers supervise the loading and unloading of cargo, monitor security and stay in communication with other vessels and port authorities. These duties require constant attention from the senior deck officers.
  • Safety Officer Duties — Third mates are often in charge of ensuring safety aboard large ships. They’re known as “safety officers,” and they must maintain compliance with U.S. Coast Guard regulations for all safety equipment. This includes monitoring firefighting, first aid and personal survival gear, as well as being prepared to dispatch and operate lifesaving vessels in an emergency.

Questions? Contact a school advisor here.

Questions? Contact a School Advisor


How to Become a Third Mate

The first step to becoming any high-ranking member of a ship’s crew is gaining experience. You have to put in your time working the lower-level positions so that when you advance, you understand how to be a better manager of your personnel. Crew members appreciate a supervisor who works with them and appreciates their working needs.

Once you accumulate enough experience and sea time, you’ll be able to enroll in a USCG-approved maritime training school and be on your way to a promotion. The most common way to become a third mate is by first becoming an Able Seaman. An AB is the entry-level deck position and allows you to gain the experience needed to become an officer. If you don’t have your able seaman endorsement, you can take a short class that will allow you to pursue it.

You can also apply for a maritime apprenticeship program to become a third mate, which gives fast and cost-effective solutions for individuals who have little or no maritime experience. During these apprenticeship programs, you can gain the experience and qualifications needed to become a third mate.

Learn More About Maritime Apprenticeship Programs

Here is what you’ll need to get your third mate license.

Complete Sea Service Requirements for Third Mate License

You need 1080 days of sea time. You can count any sea service from age 16 onward, but 90 of the 1080 days must be within the last three years. Remember these other requirements, too:

  • Overtime doesn’t count toward days of sea service. One day is equal to 8 hours of work.
  • Contact your marine employer for records of your sea time or fill out any other applicable time using the USCG sea service forms.
  • If it’s been a long time since you’ve filled out sea service forms, make sure you follow the Coast Guard guide to documenting sea service.

Pass a USCG-Approved Exam to Become a Third Mate

If you enrolled in a maritime training academy to get your able seaman endorsement, then you know the best way to pass your upgrade test is through a USCG-approved training school. The certificate of completion remains valid up to one year after you finish the course, so there’s time to accumulate more sea service before applying to the Coast Guard if needed.

Secure a TWIC Card to Meet Third Mate Qualifications

You need a valid TWIC card to upgrade to a third mate. You may use the card you received for your original merchant mariner credential.

Undergo a Medical Exam to Earn Your Third Mate License

Before you make an appointment with a doctor, use the USCG medical examination guide to avoid common errors that could prompt the Coast Guard to reject you. Choose a medical examiner who is familiar with USCG physicals. A few of the portions of the physical require careful attention that can easily be missed.

Enroll in Drug Testing to Meet Third Mate Conditions

If you work currently as a merchant mariner, then you’re already enrolled in a random drug screening program. Provide proof to the Coast Guard by contacting your marine employer for the drug test records. If you aren’t currently employed, find an affordable drug screening program and enroll.

Fill Out a Merchant Mariner Application Form to Become a Third Mate

To apply, use the same USCG application form that you did for your original merchant mariner credential, but be sure to specify that it’s for your third mate endorsement instead.

Pay Application Fees for the Third Mate License

Use the online payment portal and pay the appropriate fees based on your type of merchant mariner credential. Keep the payment confirmation for your records.

Fulfill the Age Requirements for Third Mate Licensing

You must be at least 19 years old to become a third mate.

To make sure there isn’t a delay in the acceptance of your application, use the U.S. Coast Guard application checklist and tick all the boxes. The fastest way to receive your endorsement is to scan your application documents and submit them through the USCG website. You can expect to receive your license in about one to three months.

Questions? Contact a school advisor here.

Questions? Contact a School Advisor

An Officer in Charge of a Navigational Watch

You’ve probably heard commanding officers referred to as OICNWs. What does it mean?

When you apply for your third mate license, there are a few endorsement types available to you based on your sea service. You can either apply for a USCG third mate oceans or near-coastal license and there are different tonnage qualifications that reflect the capacity of ships on which you’ve served. In all of these cases, you need to receive your OICNW certification.

The OICNW qualification ensures deck officers know how to operate using the safest navigational practices. It’s defined by the STCW, or Standards of Training, Certification and Watchkeeping, an internationally recognized set of rules that outlines safe marine operations. In 2010, the rules received their first significant revision since 1995, which took place in Manila, Philippines. Since the 2010 convention, some new requirements have been adopted for seafarers who plan to get an STCW endorsement.

These changes may affect you:

  • More strict evaluation requirements to ensure mariner competency
  • Increased minimum hours of rest for seafarers — to at least 10 hours in a 24-hour period
  • Additional training with up-to-date technology like electronic charts and systems
  • Environmental awareness training for marine environments
  • Updated electro-technical officer training
  • Improved guidelines for crew members working aboard hazardous container ships
  • A new security protocol, including how to respond if your vessel is taken over by pirates
  • Integration of online training programs
  • New training procedures for using Dynamic Positioning Systems

OICNW Sea Service Guidelines

If you plan on working aboard large vessels in the modern marine industry, you need to stay up to date with best practices as navigational technology evolves. These are the sea service requirements for an OICNW:

  • 1080 days of sea time aboard vessels as part of the deck crew on ocean waters, near coastal waters or in the Great Lakes. You may count service on all other navigable waters such as inland waters as half of the 1080 days.
  • Half of your 1080 days must be performed under the supervision of an officer holding the OICNW endorsement, where you performed watchkeeping duties on the service bridge during operations.
  • Days spent working in the engine department of a vessel may be used for up to 90 days of OICNW sea service.

Instead of the 1080 days of service, it’s possible to enroll in an intensive on-the-water training program through a maritime institute. In these programs, you receive your mate’s license after a year of schooling.

What to Study for the OICNW Written Exam

After you meet your sea service requirements, you must be able to demonstrate a working-level understanding of these essential OICNW skills through written examination:

  • First aid and medical procedures
  • Radar monitoring
  • Search and rescue operations
  • Visual signal techniques
  • BRM, or bridge resource management
  • Navigation, including terrestrial, celestial and electronic systems
  • Watchkeeping in compliance with COLREGS and IMO Standard Marine
  • Phrases of communication
  • Proper handling and storage of cargo
  • Ship handling
  • Best practices of stability
  • Weather prediction
  • ARPA, or Automatic Radar Plotting Aids
  • Distress signal equipment (GMDSS)
  • Electronic charting
  • Firefighting, personal survival and emergency vessel operation

If you have your Master’s license with an STCW endorsement valid for vessels over 500 gross tons or for Offshore Supply Vessels, you do not need to take a written examination. You only need to satisfy the other application requirements.

OICNW Renewal

Since January 2017, anyone wishing to renew an OICNW credential must demonstrate the following in a U.S. Coast Guard-approved training course:

  • A thorough understanding of the leadership and teamworking skills of STCW 2010, as defined in 46 CFR 11.309c1.
  • Completion of USCG-approved ECDIS training program for working aboard vessels with ECDIS systems, according to 46 CFR 11.309c2.
  • A high level of competence in Basic Training and Advanced Firefighting as in 46 CFR 11.303b.

What is the Salary of a 3rd Mate

The salary of a third mate varies widely depending on your employer. As reported by the U.S. Bureau of Labor Statistics, officer’s wages can range from $35,000 to over $135,000 per year, which equates to $17 to $60 per hour. The higher end of the spectrum is populated by officers who work for the oil industry in states like Texas and Louisiana.

Those annual salary statistics do not reflect all compensation in the merchant marine industry. When working aboard large commercial vessels, your accommodation and meals are paid for, which significantly reduce your cost of living and keeps money in your bank account. Many companies also offer their full-time employees health insurance and significant paid vacation time due to the concentrated work schedule.

If you’re brave and looking to maximize your pay per hour, marine employers offer extra compensation for crew members who work with hazardous cargo or in dangerous conditions. You may also sign up for a military reserve program, which will grant you extra benefits and a higher salary. The concentrated work schedule and additional pay opportunities for mariners mean they can retire early, often with excellent benefits.

Third Mate Training Programs

The MITAGS AB to Mate program is designed for experienced mariners looking to achieve the rank of deck officer. Our course covers all of the U.S. Coast Guard requirements to get your USCG near-coastal or third mate oceans license, as well as the STCW requirements needed for an OICNW endorsement. After completing the program, you’ll be well-prepared to work confidently as a third mate. We also offer courses to get your Tankerman Person in Charge endorsement, Medical Person in Charge endorsement and more.

The MITAGS programs are designed to maximize your time in training and not repeat information you already know. Our third mate’s course is available in three different lengths and intensities based on your skills and knowledge before starting the program:

  • We offer a five-week course for mariners who already have extensive experience with cargo operations and navigational watchstanding. This course is designed to reinforce your knowledge and get you the formal certification in what you already know.
  • Our 10-week course is intended for mariners with some experience in cargo operations and stability who need reinforcement of navigational watchstanding.
  • Our 20-week course teaches you everything you need to know to become a deck officer in the marine workforce.


What You Gain by Taking a Course With MITAGS

By the end of all courses, you will have the confidence to command a real bridge watch with no assistance. Our third mate courses include:

  • Navigation — general, near coastal and chart plotting
  • Deck safety
  • Deck general
  • Rules of the road
  • Firefighting
  • Maritime law
  • Ship handling and stability
  • Cargo handling
  • Tides, currents, and weather
  • Practice exams

The MITAGS learning environment is relaxed and professional. The third mate course contains a lot of information, and we give you personalized help throughout the entire process. Using advanced simulation technology and real-world experience from seasoned mariners, we offer a hands-on learning experience that prepares you for the workforce.


We not only help you pass the Coast Guard examination, but we also pride ourselves in keeping our curriculum relevant and useful. Check out the MITAGS AB to Mate course and realize your full potential — your future as an officer begins today.

Questions? Contact a School Advisor


TL;DR: A third mate is an officer of a ship’s deck department and is responsible for supervising many high-priority operations. To become a third mate you need to be 19 years or older, have 1080 days of sea time, pass a USCG-approved exam, secure a TWIC card, pass a medical exam and drug test, fill out a merchant application and pay application fees for your Third Made License.