Calculator · Stage 2
Tax-Loss Harvesting Savings Calculator
Model the real value of harvesting an unrealized loss — the immediate tax savings, the future tax you still owe, and the net benefit from deferral compounding.
⚠ Wash Sale Rule Reminder (IRC §1091)
Do not repurchase the same or substantially identical fund within 30 days before or after the sale. Swap into a similar-but-different fund (e.g. VTI → ITOT) and wait 31 days before switching back.
Position Details
Must be greater than market value to harvest.
Tax Rates
Reinvestment Assumptions
How long before you sell the replacement fund?
Rate used to discount future tax liability to present value.
Harvesting Analysis
Value of Deferral Over Time
What the immediate tax savings compounds to if reinvested, minus the future tax owed.
No current capital gains to offset?
Your harvested loss carries forward. Up to $3,000/year can offset ordinary income (IRC §1211). The remainder offsets future capital gains. This still has value — just over a longer horizon.
Assumptions
· Short-term loss: taxed saved at ordinary income rate (offsets ST gains first, then ordinary income)
· Long-term loss: tax saved at LTCG rate (offsets LT gains first)
· Extra future tax = additional gain created by lower cost basis on replacement fund × LTCG rate
· Net benefit = immediate savings − PV(future extra tax), discounted at your specified rate
· Wash sale rule: always reinvest in a similar but not substantially identical fund
· Step-up in basis at death would permanently eliminate the future extra tax — not modeled here