Sea-Service Letter Templates

By Captain Mike · 50 years at sea · former MITAGS faculty
Template reviewed September 2026

General Sea-Service Letter

Additional information may be required for your endorsement.

The goal is to remove ambiguity. A strong letter reports the facts of your service: who served, on what vessel, where, when, in what capacity, and for how many actual days and hours, drawn from logs and company records. The letter reports service; the National Maritime Center decides how much of it is creditable.

Ask for the company's own letter first. Most companies already have a sea-service letter template on their letterhead. Ask the office for theirs before using this one. A company letter should always be on company letterhead; one on plain paper is likely to be questioned or not accepted by the Coast Guard. If the company has no template, give them this one to put on their letterhead. Owners documenting their own small vessel use the CG-719S with proof of ownership instead. Owner-operator rules →

Copy-paste template

[COMPANY LETTERHEAD - REQUIRED FOR COMPANY LETTERS]

[DATE]

U.S. Coast Guard - National Maritime Center

RE: Sea-Service Verification for [MARINER FULL NAME]
Mariner Reference Number: [IF ASSIGNED]

TO WHOM IT MAY CONCERN:

I certify the following service aboard the vessel identified below.

VESSEL INFORMATION
Vessel name: [NAME]
Official or state registration number: [NUMBER]
Vessel type: [TYPE]
Flag: [COUNTRY]
Documented gross tonnage: [GRT AND/OR GT - IDENTIFY EACH]
Propulsion type: [TYPE]
Propulsion power: [HP OR kW]
Operating waters/routes: [SPECIFIC WATERS AND ROUTES]
Ports or terminals, where applicable: [DETAILS]

SERVICE INFORMATION
Capacity served: [POSITION]
Department: [DECK / ENGINE / OTHER]
Dates of service: [START DATE] through [END DATE]

Actual days served aboard: [NUMBER]
Of these, days underway: [NUMBER]
Other service included in the total: [NUMBER AND DESCRIPTION]

Hours worked per day: [HOURS]
Watch or work schedule: [SCHEDULE]

The service totals exclude leave and days off. Separate periods,
capacities, routes, or schedules are itemized in an attachment
where necessary.

Primary duties:
- [DUTY 1]
- [DUTY 2]
- [DUTY 3]

ADDITIONAL QUALIFICATION INFORMATION
[Provide applicable details concerning supervised bridge or engine
watchkeeping, routine radar use, STCW applicability, SOLAS status,
towing service, or an authorized two-watch arrangement. Identify
matters that are not applicable.]

This certification is based on [VESSEL LOGS / COMPANY SERVICE
RECORDS / OTHER SUPPORTING RECORDS].

I certify that the information above is true and correct to the
best of my knowledge.

[SIGNATURE]
[PRINTED NAME]
[OWNER / OPERATOR / MASTER / CHIEF ENGINEER]
[COMPANY, IF APPLICABLE]
[ADDRESS]
[PHONE]
[EMAIL]

Official references: NMC sea-service guidance & sample letter · NMC forms (CG-719S) · 46 CFR 10.232

Don't estimate. Avoid words like “approximately” and “estimated total.” Give actual days served, excluding leave and days off, and show underway days separately.

12-hour days aren't automatically 1½ days. That credit applies only in qualifying cases with an authorized two-watch arrangement. Report the hours and the schedule, and let the NMC apply the credit. NMC time-and-a-half guidance →

Service on vessels under 200 GRT? A letter should contain the same information the Small Vessel Sea Service Form (CG-719S) asks for. Owners documenting their own boat also need proof of ownership. Owner-operator rules →

Audit checklist

Check	Question
Identity	Does the name match the application? Is the mariner reference number included, if assigned?
Vessel	Are vessel name, official or registration number, type, and flag stated?
Tonnage	Is the documented tonnage given, with GRT and GT identified separately? Tonnage explained
Propulsion	Are propulsion type and power (HP or kW) stated?
Route	Are the specific waters and routes described, not “various” or a region?
Capacity	Are department and position stated?
Dates & days	Are start and end dates complete, with actual days served and underway days shown separately?
Hours	Are hours worked per day and the watch schedule stated?
Extras	If your endorsement needs it: supervised watchkeeping, radar use, towing, STCW or SOLAS details?
Letterhead	Is a company letter on the company’s official letterhead?
Signer	Is the signer the owner, operator, Master, or Chief Engineer, with contact information?
Basis	Does the letter say what records it is based on?

Official references

The letter reports service facts; the NMC determines how much credit you receive.

Before you send it: check the letter against the full list of what evaluators need. Documenting Sea Time Without Rejection →

Sea-Service Letter Templates

General Sea-Service Letter

Audit checklist

Official references

Who’s Hiring? Maritime Employer Directory