ETH Tax-Loss Harvesting Calculator: The Wash Sale Rule, Your Tax Savings and Who Is Underwater (2026)

Does the wash sale rule apply to ETH? Current law vs H.R. 10357

The wash sale rule, section 1091 of the Internal Revenue Code, blocks a loss on “stock or securities” if you buy substantially identical ones within 30 days before or after the sale. The IRS treats crypto as property (Notice 2014-21), and the staff of the Joint Committee on Taxation wrote on September 14, 2026 that digital assets are not expressly within section 1091 and that the IRS has issued no guidance applying it to them. The Digital Asset Tax Certainty Act (H.R. 10357) would change that. Here is how the two compare for an ETH holder:

The retroactive start date is the part that matters now. As introduced, section 301 applied to “dispositions after the date of the introduction of this Act”; the chairman’s substitute (JCX-50-26) replaced that with “after September 14, 2026”. So a sell-and-rebuy done today is fine under current law, but it would become a wash sale if the bill passes in this form, even in 2027. An earlier standalone bill, H.R. 9172 (June 2026), proposed the same idea and was referred to committee. Nothing has passed either chamber. For the rest of the bill (the $10 gas-fee exemption, stablecoins, staking and the crypto amnesty), see the Digital Asset Tax Certainty Act explained.

A wash sale defers a loss rather than destroying it: the disallowed loss is added to the cost of the ETH you buy back, so you get it when you sell that ETH later. The cost is timing, which matters most if you need the loss this year to offset gains.

Key dates for 2026 ETH loss harvesting

Which ETH buyers are at a loss right now?

Every year since Coinbase listed ETH, compared with the $2,385.86 close on Oct 22, 2026. “Days at a loss” is the share of that year’s daily closes above today’s price: anyone who bought on those days is underwater. The last two columns spread $10,000 evenly across every day of the year and count only the losing days’ lots, which is what you could harvest by selling those lots alone.

The pattern is clear: everyone who bought before 2021, and in 2023, has a gain. The losses sit in 2021, early 2022, 2024, 2025 and parts of 2026. ETH’s record close was $4,831.24 on Aug 22, 2025; today’s price is 50.6% below it, and 44.9% of the last 365 daily closes were higher. For the bigger picture of past declines, see the ETH drawdown history and Ethereum price history.

By purchase month, last 25 months

“Term” is whether lots bought that month would be short-term (held one year or less) or long-term if sold on Oct 22, 2026. Short-term losses offset short-term gains taxed at ordinary rates first, which usually makes them the more valuable kind. Every month back to 2016 is in the CSV.

Up overall, but with losses inside: a weekly DCA example

$100 of ETH bought at the Coinbase close every Monday from January of each start year to Oct 22, 2026. Even plans that are in profit hold many lots bought above today’s price. Selling only those lots (specific identification) realizes the loss while keeping the cheaper lots.

This only works if your records and your broker let you pick lots. The default is first-in, first-out, which would sell your oldest and usually cheapest ETH and could turn a planned loss into a gain. Since January 1, 2025 basis is tracked wallet by wallet (Rev. Proc. 2024-28), so lots in one exchange account can’t be matched against purchases in another wallet. Try your own plan in the ETH DCA simulator.

The cost of waiting 31 days to buy back

Sitting out 31 days protects the loss under either version of the law, but ETH can move a lot in a month. Across 1,360 31-day windows since January 2023, ETH’s median move was +0.3%, but the typical size of the move either way was 11.2%; it moved more than 10% in 55.2% of windows and rose more than 10% in 30.4%. One window in ten fell 20.7% or more and one in ten rose 30.1% or more. Since 2016 the swings were bigger (median absolute move 17.1%).

The table shows what ETH did in the 31 days after each December 31, the window a last-day seller would sit out. It rose in five of ten years, fell in four and was flat in one. Compare the tax you would save with the price risk of being out, and remember the loss is only deferred, not lost, if a wash sale does apply.

Swaps: ETF shares, WETH and liquid staking tokens

Some holders sell ETH at a loss and keep exposure through something similar. How each swap fares, as we read current law and the bill’s text:

Spot ETH ETFs trade like stocks and are reported on Form 1099-B, so brokers generally apply wash-sale tracking to them. There is no IRS guidance on whether two funds that hold the same asset are “substantially identical”, so the cautious approach is to wait 31 days. Swapping ETH for a liquid staking token may itself be a taxable exchange; our staking rewards tax calculator covers how staking income is taxed, and the spot Ethereum ETF comparison lists fees and which funds stake.

Other rules and the records to keep

• Loss limits. Net capital losses offset capital gains, then up to $3,000 of other income a year ($1,500 married filing separately). The rest carries forward with no expiry and keeps its short- or long-term character (IRS Topic 409).
• Holding period. Long-term means held more than one year: ETH bought on October 23, 2025 must be sold on October 24, 2026 or later to be long-term. A rebuy starts a new holding period.
• Lot identification. Without a specific identification, units are treated as sold first-in, first-out. For ETH held at a broker, IRS Notice 2026-20 extends through December 31, 2026 the relief that lets you identify units in your own books and records or by a standing order. Self-custodied ETH needs your own dated records of which units you sold.
• Related parties. Losses on sales to your spouse, parents, children, siblings or a company you control are not deductible (section 267).
• Real economics. Some advisers caution that a sale and an instant rebuy with no change in position could be questioned under general anti-abuse doctrines such as economic substance (section 7701(o)). We found no IRS ruling applying it to crypto loss sales; it is a reason to keep records showing a genuine sale.
• Forms. Sales go on Form 8949 and Schedule D. Brokers issue Form 1099-DA with gross proceeds for 2025 sales and, for 2026 sales, cost basis for ETH bought in the same account from January 1, 2026. Check the broker’s basis against your records before filing (see Form 1099-DA explained).
• Keep: trade confirmations for each sale and rebuy (date, time, ETH amount, price, fees), the lot you identified, wallet and account exports, and a note of any purchase within 30 days on either side of each loss sale, in case the bill becomes law.

For a quick estimate of tax on your other trades, use the crypto tax estimator. Holding ETH on an exchange or in your own wallet changes how you track lots; see hardware wallet vs exchange.

Method

• Prices: Coinbase Exchange ETH-USD daily candles, close at 00:00 UTC, May 18, 2016 to Oct 22, 2026 (3,808 days; three missing days in May 2016 carry the previous close). The reference price is the Oct 22, 2026 close, $2,385.86.
• “At a loss” means the purchase-day close is above the reference close. Short-term means the lot is held one year or less on Oct 22, 2026. Fees and intraday prices are ignored.
• The calculator uses 2026 federal brackets and 0/15/20% thresholds from Rev. Proc. 2025-32, nets short- and long-term results as Schedule D does, applies the $3,000 limit and reports the carryforward. It does not include state tax, the alternative minimum tax, credits or losses carried in from earlier years.
• Law status: Congress.gov actions, the bill text on GovInfo and the JCT descriptions, checked Oct 23, 2026. We’ll update this page if the bill moves.

Download the data (CC BY 4.0)

• CSV: ETH buyers at a loss by purchase month, May 2016 – Oct 2026 (126 rows)
• CSV: by year with $10k daily-DCA net and harvestable loss (11 rows)
• JSON: yearly, monthly, weekly-DCA lots, 31-day moves, Dec–Jan windows and law status

GrowYourEthereum. (2026). ETH Tax-Loss Harvesting Data: Buyers at a Loss by Year and Month, DCA Lots and 31-Day Moves [Data set]. Updated October 23, 2026. https://growyourethereum.com/tools/eth-tax-loss-harvesting-calculator. Licensed CC BY 4.0.

<a href="https://growyourethereum.com/tools/eth-tax-loss-harvesting-calculator">ETH Tax-Loss Harvesting Data: Buyers at a Loss by Year and Month, DCA Lots and 31-Day Moves</a> by GrowYourEthereum, licensed under <a href="https://creativecommons.org/licenses/by/4.0/">CC BY 4.0</a>.

@misc{growyourethereum_eth_tax_loss_harvesting_2026,
  author       = {{GrowYourEthereum}},
  title        = {ETH Tax-Loss Harvesting Data: Buyers at a Loss by Year and Month, DCA Lots and 31-Day Moves},
  year         = {2026},
  howpublished = {\url{https://growyourethereum.com/tools/eth-tax-loss-harvesting-calculator}},
  note         = {Data set, updated October 23, 2026. CC BY 4.0}
}