Tax Loss Harvesting Calculator

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

A losing investment isn't only a loss — sold strategically, it offsets your gains and up to $3,000 of ordinary income every year until used up. This calculator shows the tax you save now and what carries forward.

How to use this calculator

  1. Enter realized capital gains this year.
  2. Enter unrealized losses you can sell.
  3. Enter taxable income (for the $3,000 offset).
  4. Enter filing status.
  5. Your results appear instantly below and update as you change the numbers.

How this calculator works

Losses cancel gains dollar-for-dollar first — saving tax at your capital gains rate — then up to $3,000 of leftover loss offsets ordinary income at your marginal rate, and the rest carries forward indefinitely. The wash-sale rule blocks the deduction if you buy the same security within 30 days before or after the sale, so harvesting usually means switching to a similar fund.

Frequently asked questions

Is it worth selling at a loss?

Almost always, if you plan to hold similar exposure anyway: sell the loser, take the deduction, and buy a similar (not identical) fund — the market exposure stays, the tax benefit is yours. The exception is a position you expect to bounce back faster than 30 days.

What is the wash-sale rule exactly?

If you sell at a loss and buy the same or substantially identical security within 30 days before or after, the loss is disallowed and added to the new position's basis. Switching to a different fund or ETF in the same sector avoids it.

Can I harvest in a retirement account?

No — losses inside an IRA or 401(k) produce no deduction, and buying the same fund back there within 30 days can still trigger a wash sale against your taxable position. Harvest only in taxable accounts.

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.