Crypto tax-loss harvesting calculator

How the calculation works

1. Find the lots below cost. Value now (quantity × price) minus what you paid. Only lots showing a loss can be harvested; lots showing a gain are left alone.
2. Sort by holding period. Held one year or less is short-term; more than one year is long-term. The holding period starts the day after you bought.
3. Net against this year's gains. Short-term losses cancel short-term gains, long-term losses cancel long-term gains, and what is left of one kind is netted against the other.
4. Apply the limit. If losses exceed gains, up to $3,000 of the excess ($1,500 if married filing separately) comes off ordinary income this year.
5. Carry the rest forward. Anything beyond that carries into 2027 and later years until it is used up.

The tax saved is the difference between two full federal calculations — your 2026 tax with the harvest and without it — using the 2026 brackets, the 0% / 15% / 20% long-term rates and, above the income threshold, the 3.8% net investment income tax.

A worked example

A single filer with $140,000 of income takes the $16,100 standard deduction and has already realised $6,000 of short-term gains this year. They hold two lots below cost: one down $9,000 held under a year, one down $4,500 held longer.

• Short-term: $6,000 gain − $9,000 loss = $3,000 net loss. Long-term: $4,500 net loss. Total net loss: $7,500.
• $6,000 of the harvest cancels the gain; $3,000 comes off ordinary income; $4,500 carries into 2027.
• Federal tax without the harvest: $23,774. With it: $21,614. Saved this year: $2,160 — $9,000 of income is no longer taxed at this filer's 24% rate. The $4,500 carried forward can do the same job in a later year.

The wash-sale rule and crypto, as of 4 October 2026

The law today. The wash-sale rule — section 1091 of the tax code — disallows a loss when you sell “stock or securities” and buy substantially identical ones within 30 days before or after the sale. The IRS treats crypto you hold directly as property, not as a security (Notice 2014-21), and the rule's text does not mention digital assets. In September 2026 the staff of Congress's Joint Committee on Taxation described the position plainly: digital assets are not expressly within the rule, and the IRS has issued no guidance on whether it can apply to them.

So on this date, selling a coin at a loss and buying it back is not caught by the wash-sale rule as written. Three cautions. Tokens that are themselves stock or securities (tokenised securities) are already covered — IRS forms say so. Shares of a spot-Bitcoin ETF trade as securities, so the ordinary rule is generally understood to apply to selling and rebuying the same fund; the IRS has not said whether bitcoin and a bitcoin ETF count as substantially identical to each other. And the tax code's economic-substance doctrine (section 7701(o)) lets the IRS disregard a transaction that changes nothing but your tax bill; we found no IRS statement applying it to crypto, but an immediate sell-and-rebuy is the pattern most often flagged by commentators.

Proposals that would change it

• H.R. 10357, the Digital Asset Tax Certainty Act (Rep. Jason Smith). Approved by the House Ways and Means Committee 38–5 on 16 September 2026. Section 301 would extend the wash-sale rule to traded digital assets other than qualified dollar stablecoins, for dispositions after 14 September 2026 — a date that has already passed. Coins received for validating transactions, and regular periodic receipts you report as ordinary income, would not count as the repurchase. The bill has not been voted on by the full House or by the Senate. It is not law, and it can still change.
• H.R. 8899, the Digital Asset PARITY Act (introduced 19 May 2026) and S. 2207 (Sen. Lummis, introduced 30 June 2025) also contain crypto wash-sale provisions. Both are still in committee.

What this calculator leaves out

• State income tax. Most states tax capital gains; a harvest usually saves state tax too.
• The cost of selling and buying back — trading fees and the spread.
• The alternative minimum tax, credits and phase-outs that depend on your whole return.
• Special rates. Some NFTs may be taxed as collectibles, at up to 28% when held long-term. The IRS has said it intends to issue guidance (Notice 2023-27) and the question is not settled.
• Which lots your exchange will treat as sold. Since 2025, cost basis is tracked wallet by wallet and account by account (Rev. Proc. 2024-28). Unless you identify the specific units you are selling, the oldest units in that account are treated as sold first — which may not be the lot showing the loss. IRS relief that lets you make that identification in your own records, rather than through the broker, runs to 31 December 2026 (Notice 2026-20).

A harvest also lowers the cost basis of whatever you buy back, so some of the saving is tax deferred rather than tax removed.

The 2026 numbers used

Questions

Sources

• IRS Rev. Proc. 2025-32 — 2026 inflation adjustments — brackets, standard deduction, long-term capital gains thresholds
• IRS Form 1040-ES (2026) — 2026 Tax Rate Schedules — cross-check of the brackets and standard deduction
• 26 U.S.C. §1211 — limitation on capital losses — $3,000 limit; $1,500 if married filing separately
• 26 U.S.C. §1212 — capital loss carrybacks and carryovers — unused losses carry forward and keep their character
• 26 U.S.C. §1222 — short-term and long-term defined — long-term means held for more than one year
• IRS Publication 550 — Investment Income and Expenses — netting order; short-term losses are used first
• IRS Topic 409 — Capital gains and losses
• 26 U.S.C. §1411 and IRS Q&A on the Net Investment Income Tax — 3.8%; thresholds of $200,000, $250,000 joint and $125,000 married filing separately, not indexed
• 26 U.S.C. §1091 — loss from wash sales of stock or securities
• IRS Notice 2014-21 — virtual currency is treated as property
• Joint Committee on Taxation, JCX-47-26 — description of H.R. 10357 (14 September 2026)
• H.R. 10357 — amendment in the nature of a substitute, as approved in committee — section 301: wash-sale rules, effective date
• H.R. 10357 — text as introduced (govinfo.gov)
• IRS — Frequently asked questions on virtual currency transactions — holding period; gain and loss
• IRS Rev. Proc. 2024-28 — wallet-by-wallet basis from 1 January 2025
• IRS Notice 2026-20 — lot-identification relief extended through 2026
• IRS Notice 2023-27 — NFTs as collectibles
• 26 U.S.C. §7701(o) — economic substance doctrine

Checked 4 October 2026.