How to use Harvest
Tax-loss harvesting done carefully is four steps: know what a loss is worth, find a replacement that keeps your exposure, make sure the wash-sale rule can't claw it back, and write it down. Each step has its own page, in this order.
Size the opportunity (Calculator)
Start with what you're sitting on. Enter your tax rates and this year's realized gains — the calculator shows what harvested losses would actually be worth to you, before you touch a position.
- Value of each $1 of short-term and long-term loss, at your rates
- Estimated savings at $25K / $50K / $100K / $250K harvest sizes — or your own amount
- The "full shelter" figure: the largest harvest that still pays off this year
Find the replacement (Screener)
Search the holding you'd sell at a loss. Harvest finds its closest listed relatives — same GICS sub-industry — plus ETF stand-ins, so you can book the loss without giving up the exposure.
- Single-name peers and fund stand-ins ranked by 1 / 3 / 5 / 10-year return correlation
- Valuation metrics on any row (P/E, P/B, P/S, dividend yield, market cap, volume) — click to expand
- CSV export of the full comparison table
Check the eight traps (Wash Sale)
Before you trade, run the wash-sale checks. The 31-day timer is the easy part — the checklist covers the lookback window, IRAs, spouses, DRIPs, options, and the other ways a loss quietly gets disallowed.
- Your 61-day danger window and first safe repurchase date, from your sale date
- Red and amber flags with plain-English explanations for anything that applies
- A review date the Tax Memo picks up automatically
Document the trade (Tax Memo)
There's no IRS bright-line rule for "substantially identical," so a contemporaneous record of your reasoning is the defense. Fill in the sale and the replacement at the time of the trade.
- A one-page Tax-Loss Harvest Memorandum: the loss, the replacement, and your rationale
- Correlation evidence between sold and replacement tickers, stamped as-of date
- Wash-sale window dates and your checklist attestation — print or save as PDF for your tax file
Close the loop (Calculator)
Once the loss is booked, switch the calculator to "I have a loss" to see its current-year value and any carryforward. Don't repurchase the original security before the first-safe date from step 3 — and remember the honest framing: harvesting defers tax rather than eliminating it. The replacement starts with a lower basis; the benefit comes from timing, rate differences, and reinvesting the savings.
Value a realized loss →