Sea Time Requirements for a Captain's License
Sea service is usually the longest part of the path to a captain's license. Here's exactly what counts, how much you need, and how to document it correctly.
360
days for OUPV (Six-Pack)
~90 days must be on your route
720
days for Master 100 GRT
360 on ocean/near-coastal required
What Counts as a “Day” of Sea Service?
The USCG definition
One sea service day = 4 or more hours underway on a qualifying vessel. You can only count one day per calendar day, regardless of how many trips you take. The vessel must be actively underway — time at anchor or docked does not count.
This means if you fish every day for a season and average 6+ hours per trip, you can earn 100+ days in a single season. People who sail regularly can often qualify in 2-4 years of consistent boating — sometimes less.
Requirements by License Type
| License / Endorsement | Total Days | Route / Special |
|---|---|---|
| OUPV (Six-Pack) | 360 days | 90 days on licensed route |
| Master 100 GRT | 720 days | 360 days on ocean/near-coastal |
| Towing Endorsement (Assistance) | None beyond base | TOAR tasks required |
| Sailing Endorsement | 180 days on sailing vessels | None extra |
All requirements per 46 CFR Part 10. Verify with your Regional Examination Center before applying.
What Counts as Sea Service
Personal recreational boating (you were the operator)
Working as crew on a commercial or charter vessel
Sailing, fishing, cruising on any qualifying vessel 26+ feet
Ferries, water taxis, dive boats (as crew or operator)
Military sea service (with appropriate documentation)
Licensed commercial fishing vessel time as crew
Time at anchor or docked
Time as a passenger (not crew)
Time on vessels under 26 feet (for GRT-based licenses)
Time on non-powered vessels (sailboats count only for sailing endorsement)
How to Build Sea Time if You're Short
Get a crew job on a charter boat
This is the fastest path. Working as crew on a charter fishing boat, dive boat, or whale watch vessel earns days fast — 6-7 days a week during season. Many operations hire dockhands and deckhands with no license required.
Volunteer with the USCG Auxiliary
USCG Auxiliary operations on the water can count as qualifying sea service. Contact your local Flotilla for details.
Sail with yacht delivery crews
Delivery captains regularly need extra crew for offshore passages. One offshore passage can yield 30+ days of near-coastal or ocean route sea service.
Race crew for offshore sailboat races
Overnight offshore races count as ocean or near-coastal service. Check your local offshore sailing community for crew opportunities.
Just go boating consistently
If you already have a boat, commit to getting out 3-4 times per week. At 5+ hours per trip, you can earn 150 days per boating season. Many people qualify in 2-3 years this way.
How to Document Sea Service Correctly
The USCG requires documentation of your sea service. Poor documentation is one of the most common reasons applications are delayed or rejected.
Keep a contemporaneous logbook
The single most important thing. Log every trip: date, vessel name/registration, departure/arrival ports, hours underway, and your role (captain, crew). Don't recreate it from memory later — courts and the NMC apply greater scrutiny to retroactive logs.
Get employer letters for professional time
If you worked on a commercial vessel, get a signed letter from your employer on company letterhead confirming your dates of service, vessel name, capacity served, and approximate hours per day. This is stronger than a personal log entry.
Use the CG-719S Sea Service Affidavit
The USCG form CG-719S allows a qualified person with personal knowledge of your sea service to swear under penalty of perjury that your documented sea service is accurate. This is useful when your personal log is your only documentation.
Document route correctly
Your license will specify a route (near coastal, inland, Great Lakes, oceans). At least 90 days of your sea service (OUPV) must be on the specific route you're applying for. Make sure your log entries identify the body of water.
Don't wait until you have enough time
Start keeping a logbook immediately — even before you think about applying. Retroactive reconstruction is stressful and the NMC may reject it. Five years from now, you'll be glad you logged every trip.
Common Questions
Does fishing count as sea time?
Yes, if you were the operator or crew member, not a passenger. Recreational fishing trips where you ran the boat absolutely count. Charter fishing trips where you were a paying customer do not.
Can I count sea time on a kayak or canoe?
No. The USCG requires service on vessels at least 26 feet long for most license applications. Some interpretations allow smaller vessels for inland waters but verify this with your REC.
Does military sea service count?
Yes. Military sea service on qualifying vessels counts. You'll need a military-issued sea service letter (DD-214 or unit commander letter) confirming vessel type, duty dates, and your role.
How recent does the sea service need to be?
At least 90 days (360 for Master) must be within the past 3 years of your application. Older sea service can count toward the total but the recent requirement must be met.
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