Charitable Bunching Calculator

Last updated: August 13, 2026 · Figures for tax year 2026

With the 2026 standard deduction at $16,100 (single) / $32,200 (joint), annual giving below that amount saves zero tax. Bunching — concentrating years of donations into one tax year through a donor-advised fund — is the workaround. This calculator proves the math.

How to use this calculator

  1. Enter annual giving amount.
  2. Enter other itemized deductions (SALT, mortgage interest).
  3. Enter standard deduction.
  4. Enter marginal tax rate.
  5. Enter bunching cycle (years).
  6. Your results appear instantly below and update as you change the numbers.

How this calculator works

Giving every year, your itemized total (giving + other deductions) usually stays below the standard deduction — so the donations save nothing. Bunching every N years via a donor-advised fund: in the bunch year, N years of giving plus your other deductions clear the standard by a wide margin, and you itemize that year while taking the standard in between. The calculator totals tax saved both ways.

Frequently asked questions

What is a donor-advised fund (DAF)?

A charitable account you fund in one year (deductible then) and grant out over the following years. It is the standard vehicle for bunching — you get the deduction immediately but control the giving over time.

Does bunching change how much I give?

No — total giving over the cycle is identical. Bunching only changes the timing of the deduction, which is what makes itemizing clear the standard deduction in the bunch year.

Does a DAF cost anything?

Most providers charge a small annual fee (0.15–0.60% of the account) and some have minimums — worth checking against the tax saved, which this calculator estimates.

Disclaimer: Results are estimates for general information only and do not constitute financial, tax, or legal advice. Figures reflect 2026 rules and may change. Always confirm current limits and consult a qualified professional before making decisions. Official figures: IRS.gov · 2026 limits per IRS tax inflation adjustments.