Tax-loss harvesting calculator: how much can you save before December 31?
Selling positions that are worth less than you paid lets the loss offset the gains you have already realized this year — and up to $3,000 of your ordinary income. Import your broker’s transaction history or type what you hold, answer three questions about your tax situation, and Zyvo works out how much federal and state tax selling your losing lots today would save, with wash sales checked across everything you enter.
Every open lot is priced at today’s market price. The lots at a loss that you can sell first under first-in, first-out matching are sold, hypothetically, and Zyvo computes your tax for the year with and without those sales: short-term and long-term netting, the $3,000 limit on losses against ordinary income (the rest carries forward), the 3.8% Net Investment Income Tax and state tax for the 33 states Zyvo models. The difference is your saving.
A lot is left out when other shares of the same security were bought in the last 30 days, because selling it at a loss now would be a wash sale. Lots behind an older lot of the same holding that is at a gain are listed apart: selling them would first sell the older lot.
Selling them realizes a $4,000 short-term loss. Federal saving = 22% × $4,000 = $880
The loss cancels $4,000 of the gain, which sat in the 22% bracket. State tax comes on top where it applies. Buying the shares back within 30 days would disallow the loss.
What is tax-loss harvesting?
Selling investments that are worth less than you paid, so the realized loss offsets gains you have already realized this year. Up to $3,000 of net loss a year ($1,500 married filing separately) also offsets ordinary income; the rest carries forward to later years.
When is the deadline?
The sale has to happen by the last trading day of the year: a US sale counts in the tax year of its trade date, even when it settles in January.
How is the saving calculated?
Zyvo works out your federal and state tax for the year twice, with and without selling your losing lots today, using the same engine as the Zyvo app: short-term and long-term netting, the $3,000 limit, the 3.8% Net Investment Income Tax and the state you choose. The saving is the difference.
What is the wash sale rule?
If you buy the same or a substantially identical security within 30 days before or after a loss sale, in any of your accounts, the loss is disallowed for now and added to the cost of the new shares. The calculator checks purchases in the 30 days before today; buying again within 30 days after your sale would disallow the loss too.
Which CSV files can I import?
Your broker's transaction history with buys and sells, for example from Schwab, Fidelity, Robinhood, E*TRADE, Vanguard or Interactive Brokers, or any CSV with a date, symbol, buy or sell, quantity and price. If a column is not recognized, you can point to it by hand.
Does it work for crypto?
Crypto losses are included. The wash sale rule covers stocks and securities, and the IRS treats crypto as property (Notice 2014-21), so crypto sales are not checked for wash sales.
Is what I enter saved?
No. Your file and your answers stay on the page; only the ticker symbols are sent out, to look up today's prices. Close the page and they are gone.
Is this tax advice?
No. It is an estimate to help you plan, assuming first-in, first-out lot matching and today's prices. Check it with a tax professional before you act.