The Withholding Summary report lists all sources for Federal, State, and Local Withholding by form (W-2, 1099-MISC etc.,). At the bottom of the report, there is a field labeled All Other Withholdings (applies to only federal withholding).

Sources for withholding that are reported in the All Other Withholding field are:

• Form 8959 Line 24, Total Additional Medicare Tax Withholding
• If the taxpayer is a dual resident filing Form 1040, then from the Residency Worksheet Line 3, Tax withholding not already included (Form 1040NR, line 62a – d)
• If the taxpayer is a dual resident filing Form 1040NR, then from the Residency Worksheet Line 3, Tax withholding not already included in the return (Form 1040, line 64)