Every number on this site comes from one of four inputs: the official jackpot, the official cash value, the 2026 federal brackets, and a state rate published by that state. This page shows the arithmetic and the limits.
The formula
- Cash value = advertised jackpot × the live cash ratio. The ratio comes from the official jackpot data, not from a fixed assumption. In 2026 it has ranged from about 41% to 46%.
- Federal tax = the 2026 bracket table applied to the cash value, after the $16,100 standard deduction, single filer, no other income.
- State tax = cash value × the state's 2026 top marginal rate, except where the state exempts its own lottery (California, Pennsylvania) or has no income tax.
- Take-home = cash value − federal tax − state tax. The 24% withheld at payout is shown separately because it is a prepayment, not the liability.
Annuity
The 30 payments are derived from the game rules: 30 payments over 29 years, each 5% larger than the last, summing to the advertised jackpot. Each payment is taxed in the year received, using the same brackets and the same state rate. We assume today's brackets hold for 30 years, which they will not — that is a simplifying assumption, and it is why the annuity total is an estimate rather than a forecast.
What we deliberately do not model
- Your other income. A large salary or business income changes the marginal rate slightly at the top; at jackpot scale the effect is small.
- Married filing jointly. The calculator uses single-filer brackets. Joint filers keep marginally more.
- Itemising. The SALT cap makes itemising pointless for most jackpot winners.
- City taxes except where noted on a state page (New York City, Yonkers, Maryland counties, Indiana counties, Detroit).
- Future law changes. Rates, brackets and exemptions will change over 29 years.
- Professional fees, trusts, and state-specific claim structures.
Where the data comes from
- Jackpot and cash value: the official Powerball site and the official Mega Millions feed, refreshed every three hours. If a source fails, the last verified snapshot is kept and the "updated" stamp shows its age.
- Draw results: official published results.
- Federal brackets: IRS Rev. Proc. 2025-32 (2026 inflation adjustments).
- State rates: Tax Foundation 2026 tables cross-checked against each state Department of Revenue, with individual corrections where a state changed its rate mid-year — Georgia moved to 4.99% for 2026, for example, which several tables still show as 5.19%.
Update cadence
Jackpot numbers update automatically after every draw. State rates are reviewed quarterly and whenever a state enacts a change. Each state page carries the verification date; the site-wide date is October 23, 2026.
Accuracy and corrections
If a figure is wrong, we want to know. Email [email protected] with the state and a link to the official source. Corrections are applied to the data file and go live with the next deployment; material corrections are noted here.
Known limitations by state
Several states have rules that a single rate cannot capture: Maryland's county tax pushes the effective rate above its 6.5% state rate; New York City adds 3.876%; Indiana counties add up to 3%; Detroit adds 2.4%; and states treat nonresidents differently at claim time. Each state page flags the local layer, and the calculator uses the upper bound where a range exists, so treat those results as a ceiling rather than a precise bill.
Independence
Advertising never affects the data, the ordering of states, or which pages we publish. We do not accept payment for a rate, a ranking, or a recommendation, and we are not affiliated with any lottery operator.
Last updated October 23, 2026. Questions about this page: [email protected].