Lottery Winner Advisor Match

Charitable giving calculator for lottery winners

How much does $1 given to charity actually cost you after federal and state tax savings? The 2026 rules include a new 0.5% floor and a 35% cap that reduce the benefit for large prizes.

This calculator uses a simplified model: lottery payout = AGI; federal tax computed on AGI minus standard deduction; charitable deduction subject to 2026 OBBBA floor and cap rules. State tax savings are estimated at your state rate and may vary — not all states follow federal charitable deduction rules. Consult a CPA or fee-only advisor for jurisdiction-specific guidance.

Three rules that change the math for lottery winners in 2026

The One Big Beautiful Bill Act (OBBBA, enacted July 2025) changed the federal charitable deduction for the first time in decades. Three provisions directly affect lottery winners planning large gifts:

1. The 0.5% AGI floor

Starting in 2026, you can only deduct charitable contributions to the extent they exceed 0.5% of your adjusted gross income.1 For a $5.2M taxable lump sum, the floor is $26,000. The first $26,000 of donations produces no deduction at all. Above that, every dollar is deductible (subject to the other limits below).

Example: $5.2M AGI × 0.5% = $26,000 floor. Donate $500,000, deductible amount = $474,000.

2. The 35% cap for 37% bracket filers

For taxpayers in the 37% bracket, the OBBBA caps the tax benefit of each deductible dollar at 35 cents — not 37 cents.1 The deduction still reduces taxable income, but the resulting tax reduction is limited. A $474,000 deductible gift saves you $474,000 × 35% = $165,900 in federal taxes, rather than the $175,380 it would have saved before the cap.

Cost of the cap: On a $474,000 deductible amount, the cap costs $9,480 in foregone tax savings — meaningful, but not a reason to stop giving.

3. The 60% AGI limit

Cash donations to public charities (including donor-advised funds) remain limited to 60% of AGI.2 For a $5.2M AGI, the ceiling is $3.12M in deductible cash gifts per year. Most lottery winners giving at normal levels will never approach this ceiling.

Donor-advised fund vs. direct giving

For lottery winners, the most important giving tool is the donor-advised fund (DAF). A DAF is a charitable account at a sponsoring organization. You contribute cash (or securities) now, claim the deduction now, and then recommend grants to specific charities over months or years.

Why DAFs fit lottery winners

  • Contribute a lump sum in the year of the win to capture the full deduction while income is highest.
  • Distribute to charities on your own timeline — no rush.
  • Contribution is irrevocable, which also satisfies urgent family requests to "give to charity" without committing to a specific cause.
  • Same federal tax treatment as direct giving: subject to the 60% limit, 0.5% floor, and 35% cap.

When to consider a CRT

  • A charitable remainder trust (CRT) pays an income stream to you or a beneficiary for life or a term of years, then transfers the remainder to charity.
  • Partial upfront charitable deduction (actuarial value of the remainder interest).
  • Can convert a lump-sum win into a tax-efficient income stream.
  • Complex — requires an attorney and an irrevocable trust document.
  • Best evaluated with a fee-only advisor and estate attorney before claiming the prize.

What these numbers do not capture

The calculator models only cash gifts to public charities and DAFs (the 60% category). If you donate appreciated securities, a different 30% AGI limit applies, but you also avoid capital gains on the appreciation — sometimes the better strategy for non-lottery assets.3 The calculator also uses a simplified AGI equal to the lottery payout. Your actual AGI may differ if you have other income, business losses, or deductions from the claim year.

Related tools: estimate your gross payout with the lump sum vs annuity calculator, model the baseline tax bill with the lottery tax calculator, then read the estate planning guide for how charitable vehicles fit into a broader gifting plan with the estate planning guide.

Sources

  1. Tax Foundation: Changes to Charitable Giving Under the One Big Beautiful Bill Act — 0.5% floor and 35% cap for 37% bracket filers, effective 2026 tax year.
  2. IRS Topic 506, Charitable Contributions — 60% AGI limit for cash donations to qualifying public charities and DAF sponsoring organizations.
  3. IRS Publication 526 (2025), Charitable Contributions — 30% AGI limit for appreciated property donations; deduction mechanics for trusts and non-cash property.
  4. IRS Rev. Proc. 2025-32 — 2026 tax parameters: standard deduction $16,100 single / $32,200 MFJ; 37% bracket threshold $640,600 single / $768,700 MFJ.

Values verified against 2026 sources as of June 2026. Federal tax brackets and standard deduction from IRS Rev. Proc. 2025-32. OBBBA charitable changes from Tax Foundation analysis. State tax rules vary — verify with a local CPA.

Get matched before the giving plan is finalized

Charitable giving strategy — DAF sizing, CRT feasibility, qualified opportunity zone investments, and private foundation costs — belongs in the first-year plan, not as an afterthought. A fee-only advisor can model the full picture alongside taxes, cash safety, and family support boundaries.