When to renew your captain's license
46 CFR 10.227(b) states that a credential "may be renewed at any time during its validity and for 1 year after expiration." In practice, the National Maritime Center (NMC) accepts renewal applications up to 12 months before your credential's expiration date, and most captains apply 4–6 months out to leave room for the medical certificate, any sea-service paperwork, and NMC processing.
The 1-year window after expiration is a renewal grace period only — the credential is not valid for use after it expires, so you cannot legally exercise its authority during the lapse window.
The five ways to meet the renewal requirement (46 CFR 10.227)
To renew, 46 CFR 10.227(e)(1) requires you to demonstrate continued professional competence using ONE of five options:
1. Sea service — at least 1 year of sea service during the past 5 years. The USCG counts a year of sea service as 360 days (46 CFR 10.107), documented on form CG-719S.
2. Open-book exercise — pass a comprehensive, open-book exercise covering the general subject matter of your endorsement.
3. Approved course — complete a Coast Guard-approved refresher or recertification training course.
4. Related employment — at least 3 years during the past 5 years in a qualifying position (instructor, or the operation, construction, or repair of vessels). Deck officers using this option must also pass an applicable open-book Rules of the Road exercise.
5. Teaching — provide evidence of teaching Coast Guard-approved courses relevant to the endorsement at least twice within the past 5 years.
The open-book renewal exercise
Most recreational captains who don't have a fresh year of sea service choose the open-book exercise. It is a comprehensive, open-book test on the general subject matter of the credential; for deck endorsements that centers on the Rules of the Road. It is typically completed at home or at an approved course provider rather than at a Regional Examination Center.
Because it is open-book and untimed at many providers, the renewal exercise is far less demanding than the original closed-book exam series — but you still need to know where to find each answer in the Navigation Rules.
USCG captain's license renewal forms — the complete package
46 CFR 10.227(d) defines what a renewal application must contain. The package is the same MMC paperwork family you used for the original credential, minus the original-issue exam:
1. CG-719B — the signed application for the Merchant Mariner Credential. Every renewal includes one.
2. Medical certificate — an unexpired USCG medical certificate, or a CG-719K medical application submitted together with the renewal.
3. Drug-test evidence — a passing chemical test result (documented on CG-719P) or proof of enrollment in a random testing program.
4. TWIC evidence — a valid Transportation Worker Identification Credential or proof you have applied for one.
5. Fee payment — $95, or $140 with the open-book exercise (see the cost section below).
6. Consent to a National Driver Register (NDR) check — built into the application.
7. CG-719S sea-service forms — only if you renew on the 1-year-of-sea-service option; one form per vessel under 200 GRT.
Whichever 46 CFR 10.227(e) competence option you choose, its evidence (sea-service forms, course completion certificate, open-book exercise, or teaching/employment documentation) rides along with this package.
Medical certificate, drug test, and TWIC
46 CFR 10.227(d)(6) requires that you hold an unexpired USCG medical certificate or submit a medical certificate application with your renewal. See our medical certificate guide for the CG-719K exam and how long a certificate stays valid.
You must also satisfy the chemical-testing requirement (a current drug test result or proof of enrollment in a random testing program), and hold a valid Transportation Worker Identification Credential (TWIC), which runs on its own 5-year cycle.
How much USCG captain's license renewal costs
Renewal fees are set in 46 CFR 10.219. For an MMC with an officer endorsement, renewal is a $50 evaluation fee plus a $45 issuance fee — $95 total if you renew on sea service or an approved course. If you take the open-book exercise, add the $45 examination fee for a total of $140.
You may pay each phase separately: the evaluation fee when you submit the application, the examination fee before the exercise, and the issuance fee before the credential is printed. These are USCG fees only; an approved course or exam-prep provider charges separately.
Renewing an expired or lapsed captain's license
If your credential has been expired for less than 1 year, you renew with the same package as an on-time renewal — you simply may not work under the credential until it is reissued.
If it has been expired for more than 1 year, 46 CFR 10.227 requires you to demonstrate continued professional knowledge by completing a course approved for that purpose OR by passing the complete examination required for original issue. This is a knowledge demonstration, not necessarily a full re-evaluation of your original sea service. Active-duty military members may extend the grace period by the length of service that prevented timely renewal.
Document of Continuity — keeping a license alive without renewing
If you cannot (or don't want to) meet the renewal requirements right now — say you've stopped running trips and have no recent sea service — 46 CFR 10.227(g) lets you exchange the credential for a Document of Continuity instead of letting it lapse.
A Document of Continuity does not expire and does not entitle you to serve as a merchant mariner. What it does is preserve your eligibility: when you are ready to operate again, you renew by meeting the normal 46 CFR 10.227 requirements, rather than starting over with a new original application and the full closed-book exam series. It is the standard move for captains stepping away from the water who want to keep the door open.