Form 4972 is a tax form used by the Internal Revenue Service (IRS) to calculate the tax on lump-sum distributions received from qualified retirement plans or annuities. A lump-sum distribution is a one-time payment of the entire balance of a retirement plan, often paid to a retiree at the time of retirement. The IRS requires that taxes be paid on these distributions, and IRS Form 4972 is used to calculate the amount owed.