41 CFR § 301-76.2 - What is disposable pay?
Disposable pay is the part of the employee's compensation remaining after the deduction of any amounts required by law to be withheld. These deductions do not include discretionary deductions such as savings bonds, charitable contributions, etc. Deductions may be made from any type of pay, e.g., basic pay, special pay, retirement pay, or incentive pay.
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