Sea days needed for AB/Deckhand to mate

So I understand when it comes to unlimited licensing, you need 1080 days at sea before you can take exams to become a third mate. How many days as a deckhand or AB working onboard a tug do you need to upgrade to a limited deck license?

720 eight-hour days, 90 of those as a watchstander (the checklist doesn’t specify AB or OS) and half of total time on a vessel over 50 grt for a 500 grt mate.
720 eight-hour days, 180 of those days as a watchstander (like above, the checklist doesn’t specify as an AB or OS) and half of total days on a vessel over 100 grt for a 1600 grt mate.
Go to the NMC website to see if i am right or wrong, because i may be mistaken or misinterpreted the checklists (best you get acquainted with the checklists) All the checklists are there for future reference.


AB Unlimited – 1080 days deck service on Oceans or Great Lakes.

It takes the same number of days to get a 3rd Mates license just a lot more classes and study. You can do both at same time. Get the book “The New Hawsepipe” by Leonard Lambert. Shows how to do both at same time.

46 CFR Part 11 Subpart D.