Near coastal vs inland vs Great Lakes sea time
Inland days are shoreward of the 46 CFR Part 7 boundary lines, near coastal days are seaward of them out to 200 miles (100 for an OUPV), and Great Lakes days are on the Great Lakes and their connecting waters.
The route on your credential depends on these counts: 90 near coastal days for a near coastal OUPV, 360 for a near coastal Master, 90 Great Lakes days for a Great Lakes route.
The three kinds of water
| Waters | What it covers | Box on the form |
|---|---|---|
| Inland | Navigable waters shoreward of the boundary lines, excluding the Great Lakes | Shoreward of the boundary line |
| Near coastal | Ocean waters within 200 miles offshore; 100 miles for an OUPV | Seaward of the boundary line |
| Ocean | Waters seaward of the boundary lines, beyond near coastal | Seaward of the boundary line |
| Great Lakes | The Great Lakes and their connecting and tributary waters | Great Lakes |
The boundary lines are published in 46 CFR Part 7 and usually run across the mouths of bays and harbors. A day on a large bay inside the line is an inland day, even if the water is wide and rough. The guidance also says any description of waters that does not qualify as Great Lakes or near coastal is treated as inland, so describe the waters in words on the form.
Which days count toward which route
- OUPV near coastal: 360 days on any waters, at least 90 of them on ocean or near coastal waters (46 CFR 11.467(c)).
- OUPV Great Lakes and inland: 360 days on Great Lakes or inland waters, at least 90 on the Great Lakes (46 CFR 11.467(d)).
- Master near coastal under 100 GRT: 720 days, at least 360 on ocean or near coastal waters; Great Lakes and inland days count for up to 360 (46 CFR 11.428(a)).
- Master Great Lakes and inland under 100 GRT: 360 days, 90 on the Great Lakes for the Great Lakes route (46 CFR 11.455(a)).
One reading to know about for the near coastal OUPV: 46 CFR 10.232(b)(2) says inland service may be credited toward a near coastal endorsement for at most 50 percent of the required service, while 10.232(c) and 11.467(c) read as counting service on any waters day for day. This site follows the second reading and does not cap inland days in the 360 day total. If more than 180 of your days are inland, ask the evaluators which reading they apply before you count on them.
The NMC's evaluation checklist for the near coastal Master credits Great Lakes days day for day and caps only inland days. This site follows the regulation text and caps Great Lakes and inland together, so its count is never higher than the rule allows.
Worked example: 750 days, three kinds of water
A boater has 380 inland days, 120 Great Lakes days and 250 near coastal days, all recent. Counted by this site's engine:
- Near coastal OUPV: 750 days count, and every published number is met.
- Great Lakes and inland OUPV: 500 days count, since near coastal days are not Great Lakes or inland; every number is met.
- Near coastal Master: only 610 of 750 days count, because Great Lakes and inland days stop at 360. The line reads: needs 110 more near coastal or ocean days.
Common mistakes
- Logging a big bay as near coastal when it is inside the boundary line.
- Expecting all inland days to count toward a near coastal Master.
- Leaving the body of water description off the form.
- Mixing up the 100 mile OUPV limit with the 200 mile Master limit.
Count your own days
The log applies the day rule to every trip as you enter it, one day per calendar day, and the progress page shows your totals by waters against each credential's published numbers. Everything stays in this browser.
Frequently asked questions
Is the Intracoastal Waterway near coastal?
Usually not. Most of the Intracoastal Waterway runs behind barrier islands, shoreward of the boundary lines, which makes those days inland. Check the boundary line for your stretch in 46 CFR Part 7 before you log it.
Do Great Lakes days count toward a near coastal OUPV?
They count toward the 360 day total. For the 90 day near coastal part the regulation names ocean or near coastal waters; the evaluation checklist also lists Great Lakes days, so ask the evaluators if you rely on them.
What if one trip crossed the boundary line?
Log the hours on each side. This site gives the day to the water with the most hours, and to the lower credit water on a tie.
Sources
Last reviewed 27 September 2026 against:
- 46 CFR 10.107, Definitions in subchapter B (Day, Month, Year, Near-coastal, Inland waters, Great Lakes), Electronic Code of Federal Regulations, current text, up to date as of 24 September 2026, read 27 September 2026. Used for: Definitions of near coastal, inland, oceans and Great Lakes.
- 46 CFR 10.232, Sea service, Electronic Code of Federal Regulations, current text, up to date as of 24 September 2026, read 27 September 2026. Used for: How Great Lakes and inland service is credited toward near coastal endorsements, paragraph (b), including the 50 percent cap in (b)(2), and paragraph (c).
- 46 CFR 11.467, Operator of Uninspected Passenger Vessels of less than 100 GRT, Electronic Code of Federal Regulations, current text, up to date as of 24 September 2026, read 27 September 2026. Used for: OUPV routes.
- 46 CFR 11.428, Master of near-coastal self-propelled vessels of less than 100 GRT, Electronic Code of Federal Regulations, current text, up to date as of 24 September 2026, read 27 September 2026. Used for: Near coastal Master waters.
- 46 CFR 11.455, Master of Great Lakes and inland self-propelled vessels of less than 100 GRT, Electronic Code of Federal Regulations, current text, up to date as of 24 September 2026, read 27 September 2026. Used for: Great Lakes and inland Master waters.
- Sea Service (crediting sea service, what counts as a day, completing the small vessel sea service form), National Maritime Center, dated 12 August 2024, read 27 September 2026. Used for: Waters not qualifying as Great Lakes or near coastal are inland.
- Evaluation checklist MCP-FM-NMC5-15, National Master of vessels of less than 100 GRT upon near coastal waters, National Maritime Center, dated 15 September 2025, read 27 September 2026. Used for: Great Lakes credited day for day on the near coastal Master checklist.
This guide is our own summary of the published documents, not legal advice and not a finding about your eligibility; the credentialing authority decides. If it disagrees with the current documents, the documents win. Sea Time Ledger is not affiliated with, endorsed by, or connected to the United States Coast Guard, the National Maritime Center or any other government body.