Tax Loss Harvesting Estimator

This tool helps individual investors estimate potential tax savings from selling underperforming investments to offset capital gains. It’s designed for personal budget managers, financial planners, and anyone handling taxable investment accounts. Use it to plan year-end tax strategies without complex manual math.

📉 Tax Loss Harvesting Estimator

Calculate potential tax savings from selling underperforming investments

Gains from investments held ≤ 1 year
Gains from investments held > 1 year
Losses from sold investments held ≤ 1 year
Losses from sold investments held > 1 year
Tax rate on short-term gains (ordinary income rate)
Preferential tax rate on long-term gains

Tax Harvesting Breakdown

Net Short-Term Gain/Loss
$0.00
Net Long-Term Gain/Loss
$0.00
Total Net Capital Gain/Loss
$0.00
Estimated Tax Savings
$0.00
Ordinary Income Offset
$0.00
Loss to Carry Forward
$0.00

Setting Up the tax loss harvesting Inputs

Follow these steps to generate an accurate tax loss harvesting estimate:

  1. Gather your year-to-date capital gains and losses from your investment account statements.
  2. Enter your short-term and long-term capital gains in the corresponding input fields. Short-term refers to investments held for 1 year or less, long-term for more than 1 year.
  3. Enter the total short-term and long-term capital losses from investments you have already sold this year.
  4. Select your applicable short-term and long-term capital gains tax rates from the dropdown menus. These rates are based on your ordinary income tax bracket for short-term gains, and preferential rates for long-term gains.
  5. Check the box if you want to apply net capital losses to offset up to $3,000 of ordinary income, per IRS rules.
  6. Click the Calculate Tax Savings button to view your detailed breakdown, or Reset Form to clear all inputs.

The Expression We Use

This estimator follows IRS capital loss offset rules for U.S. taxpayers:

  • Short-term capital losses (STCL) offset short-term capital gains (STCG) first. Any remaining STCL then offset long-term capital gains (LTCG).
  • Long-term capital losses (LTCL) offset long-term capital gains (LTCG) first. Any remaining LTCL then offset short-term capital gains (STCG).
  • Net capital losses (total losses exceeding total gains) can be used to offset up to $3,000 of ordinary income per tax year. Remaining net losses carry forward to future tax years with no expiration.
  • Tax savings are calculated as: (Offset Gains * Applicable Tax Rate) for each gain type, summed across all offset amounts.

All calculations use dollar amounts and percentage rates entered by the user. No external data is pulled for tax rates, so ensure you enter the correct rate for your filing status and income level.

Reading the Output Carefully

Keep these finance-specific tips in mind when using this estimator:

  • Tax loss harvesting only applies to taxable investment accounts. Gains and losses in 401(k)s, IRAs, and other tax-advantaged accounts do not affect your tax liability.
  • The IRS wash sale rule prohibits claiming a loss if you buy the same or substantially identical investment within 30 days before or after the sale. This estimator does not account for wash sales, so adjust your loss amounts manually if this applies.
  • Long-term capital gains tax rates are generally lower than ordinary income rates, so prioritize offsetting short-term gains first if possible to maximize tax savings.
  • Carryforward losses retain their original character: short-term losses carry forward as short-term, long-term as long-term, which this estimator simplifies for general planning purposes.

What You Can Do With the Result

Tax loss harvesting is a common year-end strategy for investors to reduce their tax burden, but manual calculations are prone to errors. This tool eliminates guesswork by:

  • Automatically applying IRS offset rules so you don’t have to memorize complex ordering requirements.
  • Breaking down savings across gain types to help you prioritize which losses to realize.
  • Accounting for ordinary income offsets and carryforward losses to give a complete picture of your tax position.
  • Letting you test different scenarios (e.g., selling an additional investment at a loss) to see how it affects your tax savings.

It is designed for individual investors, financial planners, and anyone preparing their own tax returns to make informed decisions about year-end investment moves.

Short Answers

Can I use this tool for tax filing in countries outside the U.S.?

This estimator follows U.S. IRS capital loss rules. The numbers above are estimates built from the inputs you supplied, not a verified figure from any authority.

What if I have more losses than gains?

Net capital losses (losses exceeding gains) can offset up to $3,000 of ordinary income per year. Any remaining losses carry forward to future tax years indefinitely, which this tool calculates automatically.

Does this tool account for the wash sale rule?

No, this estimator does not factor in wash sales. If you repurchase the same investment within 30 days of selling it at a loss, the IRS disallows the loss. Subtract any wash sale losses from your total losses before entering them into the tool.

Other Things to Verify

Always verify your results with a qualified tax professional before making investment decisions. This tool provides estimates only and does not constitute tax advice.

  • Update your inputs regularly as you realize new gains or losses throughout the year.
  • Use the copy-to-clipboard feature to save your estimates and share them with your financial planner or tax preparer.
  • Remember that tax loss harvesting only makes sense if you have realized gains to offset, or if you want to lock in losses to use in future years.
  • Consider your overall investment strategy before selling underperforming assets: don’t sell an investment just for the tax break if it no longer fits your long-term portfolio goals.

Scope of this tool: Outputs are arithmetic results from the inputs you enter. They are not recommendations, professional opinions or verified records.