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Charitable Bunching Calculator

Same gifts, same charities — two different tax bills.

Bunching — stacking two years of charitable gifts into one tax year through a donor-advised fund — has been standard advice since 2018. But 2026 changed the math twice: a new 0.5%-of-AGI floor trims itemized gifts, and a new above-the-line charitable deduction ($1,000 single / $2,000 joint) now rewards NON-itemizers every single year — which bunching surrenders in the off year. For some households bunching still saves thousands; for others spreading now wins. This calculator runs both strategies across two years with your real numbers and picks the winner in dollars.

Why people use this

Consistent givers use it to learn whether bunching still beats spreading under the 2026 rules — the new 0.5% AGI floor and the $1,000/$2,000 above-the-line deduction flipped the answer for a lot of households, and the two-year dollar comparison settles it in one pass.

How it works

1. Enter filing status and AGI — the 2026 standard deduction and brackets are applied automatically.
2. Enter other itemized deductions (SALT after the cap, mortgage interest, medical) — the itemize-vs-standard calculator can compute this for you.
3. Enter annual charitable giving.
4. The calculator runs two years both ways: spread (each year picks the better of itemized vs standard + above-the-line) versus bunched (double gift year one, standard year two), with the 0.5% AGI floor applied.
5. The winner is shown as two-year federal tax saved — same generosity, lower bill.

Common questions

How does charitable bunching work with a donor-advised fund?

You contribute two (or more) years of gifts to a DAF in one tax year and take the full deduction immediately — then grant the money to charities on your normal schedule from the fund. The charities see no difference; your tax return does. Contributing appreciated stock instead of cash adds a second win: no capital gains tax on the appreciation.

Why might bunching NOT be worth it in 2026?

Two new OBBBA provisions cut against it. Itemized charitable gifts now face a 0.5%-of-AGI floor, and non-itemizers get an above-the-line deduction up to $1,000/$2,000 per year — every year you take the standard deduction. Bunching only wins if the bunched year clears the standard deduction by enough to offset both the floor and the lost above-the-line amounts. For households with modest other deductions, spreading now wins.

When is bunching clearly right?

When your other itemized deductions (SALT + mortgage interest) already sit near the standard deduction — common in 2026 with the $40,400 SALT cap — so a doubled gift year clears it by a wide margin. It's also ideal in a one-time high-income year (bonus, Roth conversion, business sale), because deductions are worth most at your highest bracket. Run the numbers; the two-year savings answer is what matters.

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