It depends on whether this is considered taxable or not.
If your W-2 has nothing in Box 1, and Box 12 is marked "J", then you don't have to report it at all, you just keep it for your records.
If there is a taxable amount shown in Box 1 of your W-2,you would report this in the same place you report other W-2's: Federal Taxes>Wages and Income> Wages and Salaries (Form W-2).
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