5 U.S.C. § 3523

(a) A voluntary separation incentive payment under this subchapter may be paid to an employee only as provided in the plan of an agency established under section 3522. (b) A voluntary incentive payment— (1) shall be offered to agency employees on the basis of— (A) 1 or more organizational units; (B) 1 or more occupational series or levels; (C) 1 or more geographical locations; (D) skills, knowledge, or other factors related to a position; (E) specific periods of time during which eligible employees may elect a voluntary incentive payment; or (F) any appropriate combination of such factors; (2) shall be paid in a lump sum after the employee’s separation; (3) shall be equal to the lesser of— (A) an amount equal to the amount the employee would be entitled to receive under section 5595(c) if the employee were entitled to payment under such section (without adjustment for any previous payment made); or (B) an amount determined by the agency head, not to exceed $25,000; (4) may be made only in the case of an employee who voluntarily separates (whether by retirement or resignation) under this subchapter; (5) shall not be a basis for payment, and shall not be included in the computation, of any other type of Government benefit; (6) shall not be taken into account in determining the amount of any severance pay to which the employee may be entitled under section 5595, based on another other 1 separation; and (7) shall be paid from appropriations or funds available for the payment of the basic pay of the employee.