Master 100 GRT Captain's License
The Master 100 GRT is the step above the Six-Pack license. It unlocks larger vessels, unlimited passengers, and more career options. Here's what it takes to earn it.
720
Days sea service
6
Exam sections
19
Minimum age
$697
NailTheTest prep
What the Master License Authorizes
The Master 100 GRT credential is significantly more powerful than the OUPV. It authorizes you to:
Unlimited passengers
Carry as many passengers as the vessel's Certificate of Inspection allows — not capped at 6.
Inspected vessels
Operate vessels that require a USCG Certificate of Inspection (COI) — ferries, large charter boats, crew vessels.
Career advancement
Serve as mate on larger vessels, qualify for higher tonnage upgrades (200, 500, 1600 GRT), and access commercial maritime jobs.
OUPV privileges included
A Master license includes all OUPV privileges — you don't need a separate OUPV if you hold Master.
Requirements
Age & citizenship
Minimum age 19 (vs 18 for OUPV). U.S. citizen or resident alien. No age requirement for most endorsements.
Sea service — 720 days
720 days of documented sea service on vessels 26 feet or longer, with at least 360 days on ocean or near-coastal waters. At least 90 days must be as operator or watchstanding officer. A "day" = 4+ hours underway.
Medical
USCG-accepted medical exam (not Coast Guard — any licensed physician). Must certify color vision, hearing, and physical fitness. Valid for 2 years.
Drug test
DOT/USCG-approved drug screening within 185 days of application.
TWIC card
Transportation Worker Identification Credential — required for all MMC holders. Apply through TSA. Costs ~$125 and takes 2-4 weeks.
First aid training
Current first aid and CPR certification required (American Red Cross, AHA, or equivalent).
Pass all 6 exam sections
Two sections require 90% (Rules of the Road, Chart Plotting). Four sections require 70%. All sections are taken at a USCG Regional Examination Center (REC).
The 6 Exam Sections
The Master exam builds on the OUPV's 4 sections and adds 2 more. If you already hold an OUPV, you only need to pass the 2 highlighted Master sections.
| Section | Questions | To Pass | Covered by |
|---|---|---|---|
Rules of the Road COLREGS, inland rules, lights, shapes, sounds. Closed book. | 50 | 90% | OUPV + Master |
Deck General / Safety Seamanship, stability, engines, fire, lifesaving, maritime law. | 50 | 70% | OUPV + Master |
Navigation General Aids to navigation, compass, tides, weather, electronics. | 50 | 70% | OUPV + Master |
Chart Plotting Dead reckoning, course plotting, fixes, set & drift. Hands-on. | 10 | 90% | OUPV + Master |
Master Deck Vessel stability calculations, cargo operations, advanced seamanship. | 50 | 70% | Master only |
Master Navigation Celestial navigation, voyage planning, electronic navigation systems. | 50 | 70% | Master only |
Upgrading from OUPV to Master
The most common path is to earn your OUPV first, then upgrade once you have 720 days of sea service. Operating under your OUPV license counts toward the Master sea time requirement.
Upgrade checklist
- • Accumulate 720 total days (360 more after OUPV minimum)
- • Pass Master Deck and Master Navigation exam sections at your REC
- • Updated physical (if your current one is expiring)
- • Current drug test (within 185 days)
- • File new CG-719B application at your REC or online via NMC
Study for the Master 100 GRT Exam
NailTheTest's Master 100 GRT plan ($697) covers all 6 exam sections with 1,628+ practice questions, 866+ flashcards, structured lessons, and an private tutor. Or get Captain's Complete ($797) and add Sailing and Towing endorsements at no extra cost.