Yes, they do. If you operate a documented vessel on Wisconsin waters, the vessel must also be registered in Wisconsin. You have to do this if you have used the vessel in Wisconsin for more than 60 consecutive days or if Wisconsin is the state of principal use for your vessel.
The one exception: commercial fishing vessels that operate on Wisconsin waters for 60 consecutive days or less with a home port that’s located outside of the state.
To apply, your Certificate of Documentation must be current and you must attach a photocopy of the front and back of your COD as part of the application.
Boating laws in Wisconsin do not require you to display the registration number. But, on your vessel’s transom, the expiration decals must be displayed on either side of the vessel’s name. The registration number and decals have to be displayed as they are for undocumented vessels if and only if the expiration decals are not displayed beside the vessel’s name.