What taxes will an employee have to pay when a company offers a voluntary payout for their position?

These programs take many, many forms and can cover many items in addition to salary replacement. Your Human Resources dept should be well prepared, and about the only ones that can answer what each portion of the specific package provides and will be taxed. Generally, any money received as an addition or replacement for income is going to be taxed like ordinary income. Aspects that may involve the lump sum payout of a pension plan may have special considerations. Portions that are for a continuation of otherwise non taxed benefits (say medical coverage) also may be treated seperately. Frequently, the amount being paid is NOT allowed to be considered toward a 401K contribution. Things like stock options or employee stock have different rules and again depend on many factors of how the base plan was established (qualified or not), and the ending package is structured. Sometimes, certain portions may not be subject to certain lower level tax contributions, like unemployment, etc., and some may be taxed like a capital gain.