How to use this calculator
- Enter the inputs using consistent units.
- Review rate, timing, and scope assumptions.
- Select Calculate to update every result.
- Change one assumption at a time to compare scenarios.
#3304 · Finance Tool
Tax Loss Harvesting After Tax Value Calculator
Compare the projected after-tax value of harvesting an investment loss with leaving the position unchanged. The model includes the immediate tax benefit, reinvestment growth, a replacement asset, and tax due on the harvested basis difference at sale.
Calculator
Enter assumptionsFormula
After-tax value = (loss × current tax rate) × (1 + return)years − (loss × future tax rate) − costs
What the result means
A positive result is the modeled advantage attributable to the harvested loss, not the total account value. Actual value depends on when and how the loss is used and whether replacement holdings track the original investment.
This is an educational estimate, not tax, legal, or investment advice. Tax rules, eligibility, account ordering, and state treatment vary; confirm decisions with a qualified professional.
Example calculation
A $10,000 loss at a 30% current rate creates a $3,000 benefit. At 7% for 10 years it grows to $5,901.45. Subtracting $2,000 future tax and $100 cost leaves $3,801.45.
Tips for better results
- Keep units consistent from input through result.
- Use unrounded values during the calculation and round only the displayed result.
- Run a conservative and an optimistic scenario before acting.
- Document assumptions so the estimate can be reproduced.
Frequently asked questions
Does tax-loss harvesting permanently eliminate tax?
Usually it defers tax by lowering replacement basis; the model subtracts future tax on that basis difference.
Can a harvested loss offset ordinary income?
Rules and limits depend on jurisdiction and circumstances; enter only the rate applicable to the loss you expect to use.
Does this model the wash-sale rule?
No. It assumes the harvest is implemented without disallowance.
Why include trading and tracking cost?
A replacement investment may create transaction costs or performance differences that reduce the benefit.
Is the result the value of my entire portfolio?
No. It is the estimated incremental after-tax value of the harvesting decision.
Related calculators
After-tax value components
| Component | Model treatment |
|---|---|
| Current tax benefit | Loss × current marginal rate |
| Reinvestment | Compounded for the holding period |
| Basis effect | Loss × future gains rate |