Notice 2018-64 allows three alternative methods of computing W-2 Wages for QBI.  The first is to use W-2 Box 1 wages, which will exclude Box 12 voluntary deductions from taxable income.  The second allows W-2 Box 12 income to be added to Box 1 income, but Box 1 wages that are not wages for Federal income tax withholding purposes must be subtracted (for example, supplemental unemployment compensation benefits) .  The third requires actual tracking of wages subject to withholding that are reported in Box 1, and adding Box 12.  In almost all instances, the addition of Boxes 1 and 12 will likely produce an permissible result, but not always.