Out-of-state vendors must collect tax if they have a physical presence or meet economic thresholds ($100,000 in annual sales or 200+ transactions in Michigan).
Michigan's 6% sales and use tax applies to "tangible personal property," which the state defines to include (canned) computer software. Maintenance agreements follow these specific triggers: Michigan Sales Tax On Software Maintenance
In Michigan , the taxability of software maintenance agreements depends heavily on whether the contract is or optional , and the nature of the software it supports. Key Taxability Rules for Maintenance Out-of-state vendors must collect tax if they have