Nate Gilman
What day does the USCG count back from to calculate my 360 sea days in the last 5 years for renewal?
The USCG will count back 5 years from the day your application is submitted to the USCG REC.

As an example if your application is submitted on January 04, 2023 you would get credit for all of the sea days since January 04, 2018. This is unrelated to your MMC expiration date and is solely dependant on when your application is submitted to the USCG.
How do I renew my USCG License?
To determine if you need to take courses to renew your license you need to first Count up how many creditable sea days you have in the last 5 years. (MM-SEAS does this automatically for you).
Count up how many creditable sea days you have in the last 5 years.
If you have less than 360 days in the last 5 years, renewing your USCG National endorsements is as simple as an open book take home test for each endorsement! You will have to take courses if you also hold Radar Observer, Tankerman endorsements, Proficiency in Survival Craft (PSC endorsements) and/ or International (STCW) endorsements. If you hold a Master of Towing or Mate (Pilot) of Towing you will need to complete Part D of the published TOAR for your route or a course that meets Part D in addition to the open book take home tests.

We hope this made your life a little easier and if you have other questions the MM-SEAS team is always here to help!
We do prefer to answer questions live with screen sharing to make both of our lives easier.
We hold free live virtual office hours Monday and Wednesday from 5:00 - 5:30 pm PT inside of mmseas.com under License Guidance and then Daily Office Hours.
Pro MM-SEAS members get access to our daily live office hours Monday thru Friday from 5:00 - 5:30 pm PT. You also get access to unlimited live 1 on 1 calls with one of our USCG Licensing Specialists. Pro MM-SEAS members can access these features inside of mmseas.com under License Guidance.