Lottery Annuity Calculator - Payments and Taxes

A lottery jackpot advertised as an annuity is the present value of a stream of payments, not a pile of cash sitting in an account. Winners choosing the annuity need a payment estimate after tax and a sense of what the last check is worth in today's dollars. The lottery annuity calculator treats the jackpot as the present value of an ordinary annuity, solves for the level gross payment at the advertised rate and frequency, applies a flat tax rate, and then deflates the after-tax payment by inflation over the full term to illustrate purchasing power at the end. The periodic rate i is the annual rate divided by payments per year. The number of payments n is years times frequency. Gross periodic payment is jackpot times i divided by one minus (1+i) to the power minus n, the standard annuity-payment identity. After-tax payment multiplies by one minus the tax rate. Total after-tax proceeds are that payment times n. The inflation-adjusted final payment divides the after-tax payment by (1 + inflation) to the power of the annuity years, which is a snapshot of the last check in year-zero dollars, not a full real-NPV of the stream. Use the lottery annuity calculator to compare a 30-year monthly annuity with an annual-pay structure, to see how a 37 percent tax rate shrinks each check, and to remember that a payment decades out is smaller in real terms. Lottery rules often escalate payments rather than paying a level amount; this page uses a level annuity so the math stays transparent. Cash-option lump sums are a different present-value problem and are not computed here. Tax is a single effective rate, not a complete federal-plus-state withholding schedule, and it is applied to every payment equally. Actual withholding, estimated taxes, and investment of payments after receipt will differ. The advertised rate on a jackpot is a marketing and present-value convention, not your personal return if you invested a lump sum. Payments per year should be 12 for monthly, 1 for annual, 4 for quarterly, or 2 for semiannual. This is an educational illustration, not tax advice or an official lottery quote. Confirm the cash versus annuity amounts, escalation schedule, and tax withholding with the lottery and a tax professional before you choose. Re-run when the published rate or your assumed tax rate changes.