South Carolina is a part of the Drivers License Compact (DLC) while your home state of Wisconsin is not. The DLC requires member states to inform the state in which a person is licensed about out of state moving violation convictions, while your home state of Wisconsin is not part of this agreement most states will still report violation convictions back their DOT.
According to the Wisconsin Department of Transportation, they do receive in from out of state courts information on WI licensed drivers and moving violation convictions. The WI DOT notes though that no points are assessed for convictions of traffic offenses from other states but the conviction is entered on your Wisconsin driver record.
So the SC courts will likely notify the WI DOT of this careless driving citation if you are convicted of it. Whether in Wisconsin this violation will be recorded as just a speeding ticket or a careless / reckless driving offense on your WI driving record will be up to the Wisconsin DOT so you will need to contact them for clarification.
It is possible that this South Carolina speeding citation could affect your auto insurance rates since it will be placed on your WI driving record where your insurance company can see it the next time they check your MVR. To find out for certain if it will change your car insurance rates you will need to discuss your company's rating system with your agent since insurance companies' rating systems differ from one insurer to the next.
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