The wash sale rule is a regulation enforced by the Internal Revenue Service (IRS) that disallows investors from claiming a tax loss on the sale of a security if they purchase a "substantially identical" security within 30 days before or after the sale, creating a 61-day window. This rule applies to various investments, including stocks, bonds, mutual funds, exchange-traded funds (ETFs), and options, and it prevents investors from using capital losses to reduce their taxable income while maintaining their economic position in the market. If a wash sale occurs, the disallowed loss is not deducted in the current tax year but is instead added to the cost basis of the newly acquired security, effectively deferring the tax benefit until the replacement shares are sold. The rule also extends to transactions in tax-advantaged accounts like IRAs and applies to spouses' accounts, meaning that if one spouse sells a security at a loss and the other purchases a substantially identical security within the 61-day window, a wash sale is triggered.

🌐
Charles Schwab
schwab.com › learn › story › primer-on-wash-sales
Wash-Sale Rule: How It Works & What to Know | Charles Schwab
Generally, if a security, such as stocks, exchange-traded funds (ETFs), and mutual funds, has a CUSIP number (a unique nine-character identifier for a security), then it's most likely subject to the wash sale rule.
🌐
Fidelity
fidelity.com › learning-center › personal-finance › wash-sales-rules-tax
Wash-Sale Rules | Avoid this tax pitfall | Fidelity
August 28, 2025 - When you sell an investment that ... wash-sale rule keeps investors from selling at a loss, buying the same (or "substantially identical") investment back within a 61-day window and claiming the tax benefit....
Discussions

Why does wash sale rule exist and how is tax loss harvesting anything special?
If there was no tax loss allowed you would have to pay taxes on 50K not 40K More on reddit.com
🌐 r/fidelityinvestments
15
0
April 14, 2024
Understanding wash sales: What are they? What’s the penalty? Are there any tax implications? And how can you avoid them?
Will selling FXAIX then buy VOO count? More on reddit.com
🌐 r/fidelityinvestments
8
11
March 13, 2024
Can someone explain wash sales to me?
Welcome to our sub, u/OnceInABlueMoment ! I'm happy to take a moment to assist with your wash sale inquiry this weekend. Wash sales can be complex, and traders need to recognize these transactions and the tax ramifications. Let's start with the wash sale definition. The IRS defines a wash sale as a sale or other disposition of stock or securities on which the seller realized a loss within a 61-day period (beginning 30 days before and ending 30 days after the date such sale or disposition took place) and replaces it with stock or securities that are "substantially identical." More specifically, the wash-sale rule states that the tax loss will be disallowed if you buy the same security, a contract or option to buy the security, or a substantially identical security. With this definition in mind, you may see how the trader in the Forbes article could have arrived at their situation. In short, it sounds like they kept buying the stock within the wash sale window after they sold it at a loss. This led to the loss being added to the cost basis of the newly acquired shares, and they kept repeating that cycle. It sounds like they continued to buy the stock through the year, never getting to claim any of the losses. They would've needed to sell the shares and not repurchase the stock within 30 days of the sell date to claim the loss. Now we can apply this understanding to your situation. As you mentioned, you are following a similar trading strategy to the trader in the Forbes article. If you keep incurring wash sales, you cannot claim the losses associated with the wash sales. This can lead to a tax situation where your taxable gains substantially outweigh your losses. I recommend reviewing a few resources on our website to understand the wash sale topic better. I've copied links for a couple of articles for you below. Wash sale: Avoid this tax pitfall Wash-sale rule: What to avoid when selling your investments for a tax loss Please let us know if you have any additional or follow-up questions. More on reddit.com
🌐 r/fidelityinvestments
40
16
April 15, 2023
Wash Sale Rules
No expert, but I believe a wash sale is when you sell a security for a loss and then buy that security back within 30 days of the sale. So, to avoid it anytime you sell a security for a loss, avoid a wash sale by not buying it back until 31st day. I used to worry about it but it’s pretty clearly stated on your consolidated 1099 from your broker. More on reddit.com
🌐 r/options
29
4
August 5, 2023
🌐
TurboTax
turbotax.intuit.com › tax-tips › investments-and-taxes › wash-sale-rule-what-is-it-how-does-it-work-and-more › c5ANd7xnJ
Wash Sale Rule: What Is It, How Does It Work, and More - TurboTax Tax Tips & Videos
November 1, 2025 - Under the wash sale rule, your loss is disallowed for tax purposes if you sell stock or other securities at a loss and then buy substantially identical stock or securities within 30 days before or 30 days after the sale.
🌐
Reddit
reddit.com › r/fidelityinvestments › why does wash sale rule exist and how is tax loss harvesting anything special?
r/fidelityinvestments on Reddit: Why does wash sale rule exist and how is tax loss harvesting anything special?
April 14, 2024 -

Say I have 100k to start the year. I buy two stocks. Stock A gains me $50k. I sell the stock and realize the gains. Stock B loses $10k and I sell the stock and realize the loss. I am up $40k net and will owe taxes on $40k. Where exactly is the tax loss harvest other than owing taxes on the sum of gains and losses? Where is the "tax loss harvest" benefit that we speak of?

In scenario 2, let's say I buy right back into stock B without waiting 31 days or whatever. Why does this have implications on anything? I did in fact lose and realize $10k on this stock and it isn't guaranteed I'll ever make it back.

🌐
Investor.gov
investor.gov › introduction-investing › investing-basics › glossary › wash-sales
Wash Sales | Investor.gov
A wash sale occurs when you sell or trade securities at a loss and within 30 days before or after the sale you: ... Acquire a contract or option to buy substantially identical securities. Internal Revenue Service rules prohibit you from deducting losses related to wash sales.
🌐
Investopedia
investopedia.com › terms › w › washsale.asp
Wash Sale: Definition, How It Works, and Purpose
September 19, 2025 - A wash sale occurs when an investor sells a security at a loss and then purchases the same or a substantially similar security within 30 days, before or after the transaction. This rule is designed to prevent investors from claiming capital ...
🌐
J.P. Morgan Private Bank
privatebank.jpmorgan.com › private banking & wealth management › insights › wealth planning › for your year-end tax planning, beware the wash sale rule
For your year-end tax planning, beware the wash sale rule | J.P. Morgan Private Bank U.S.
August 25, 2025 - Another key determination is whether two securities are “substantially identical”; but, the wash sale rule uses this term without precisely defining it. Ultimately, a taxpayer must consider the economics of the two positions.
Find elsewhere

sale and repurchase of a security

Wash Sale Rule
A wash sale is the sale of stock (or securities more generally) at a loss when substantially identical securities were acquired shortly before or after the date of sale. Wash sale regulations … Wikipedia
🌐
Wikipedia
en.wikipedia.org › wiki › Wash_sale
Wash sale - Wikipedia
1 month ago - In the United States, the Internal Revenue Code defines a wash sale as having occurred if securities were acquired within 30 days before or after the date of sale (a 61-day "window"). Wash sale rules can be thought of as a specific application of the doctrine of economic substance.
🌐
IRS
apps.irs.gov › app › vita › content › 10s › 10_04_011.jsp
Case Study 1: Wash Sales
Case Study 1: Wash Sales · Case Study 2: Long-Term or Short-Term · Case Study 3: Long-Term or Short-Term · Skills Warm Up: Holding Period · Case Study 4: Basis and Holding Period · Proceeds from the Sale · Case Study 1: Sales Price · Skills Warm Up: Form 1099-B ·
🌐
Washington Department of Revenue
dor.wa.gov › taxes-rates › retail-sales-tax › services-newly-subject-retail-sales-tax
Services newly subject to retail sales tax | Washington Department of Revenue
As of Oct. 1, 2025, a new law (ESSB 5814) requires that certain services now be taxed when sold. If you buy or sell these services, retail sales tax must be applied.
🌐
CCH
answerconnect.cch.com › topic › 49e2cfa27cb2100091e090b11c2ac4f1039 › wash-sales-of-stock-and-securities
Wash Sales of Stock and Securities
A comprehensive Federal, State & International tax resource that you can trust to provide you with answers to your most important tax questions.
🌐
Bullish Bears
bullishbears.com › trading education › trading help › learn to trade › trading rules › wash sale rule explained
Wash Sale Rule: Definition, How it Works, and Examples
August 28, 2025 - What is the wash sale rule? This happens when you sell a security or stock at a loss then buy it back within 30 days.
🌐
Reddit
reddit.com › r/fidelityinvestments › understanding wash sales: what are they? what’s the penalty? are there any tax implications? and how can you avoid them?
r/fidelityinvestments on Reddit: Understanding wash sales: What are they? What’s the penalty? Are there any tax implications? And how can you avoid them?
March 13, 2024 -

With tax season upon us, now’s the perfect time for a quick refresher on how wash sales work. And if you’ve still got questions, feel free to leave them in the comments below.

But first, let’s begin with a simple explanation of cost basis because the two go hand in hand:

What’s cost basis?

It’s the price you pay to purchase a stock or other investment, plus any other adjustments—like broker's fees or commissions.

OK, now on to wash sales:

What’s a wash sale?

A wash sale occurs when the same or a "substantially similar” investment is purchased within a 61-day window (30 days before or after the date you sold the loss-generating investment.) Wash sale rules apply to taxable accounts and IRAs owned by both the individual and a spouse, if applicable.

Which investments does a wash sale apply to?

These include stocks, bonds, options, mutual funds, ETFs, and reinvested dividends. (It’s considered a purchase when a dividend is issued and used to buy additional shares of a security).

What other transactions could trigger a wash sale?

Remember, you can’t get around a wash sale by selling an investment at a loss in a taxable account and then buying it back in a tax-advantaged account. In addition, the IRS has stated that it believes a stock sold by one spouse at a loss and purchased within the restricted time period by the other spouse is a wash sale. Fidelity will keep track of wash sales when they occur within the same account and by the same CUSIP, which is used to identify individual securities. If a wash sale crosses accounts or positions, then it will need to be accounted for by the taxpayer.

What’s the penalty for a wash sale?

If a wash sale does occur, you can't use the loss on the sale to offset gains or reduce taxable income. Instead, your loss will be added to the cost basis of the new investment. In addition, the holding period of the investment you sold is also added to the holding period of the new investment.

What are the tax implications of a wash sale?

In the long run, there may be an upside to a higher cost basis—you may be able to realize a bigger loss when you sell your new investment, or, if it goes up and you sell, you may owe less on the gain. If you do end up selling the new investment for a gain, the longer holding period may also help you qualify for the long-term capital gains tax rate rather than the higher short-term rate. If you end up selling the new investment for a loss, you may not have to wait as long for the wash sale window to pass. However, in the short term, you won't be able to use the loss to offset a realized gain or reduce your taxable income.

How can I avoid a wash sale?

One way to avoid a wash sale on an individual stock while still maintaining your exposure to the industry of the stock you sold at a loss, would be to consider substituting the stock with a mutual fund or an exchange-traded fund (ETF) that targets the same industry.

Some ETFs focus on a particular industry, sector, or other narrow group of stocks. These ETFs can be a good way to regain exposure to the industry or sector of a stock you sold, but they generally hold enough securities to pass the test of being not substantially similar to any individual stock.

Still got questions? Ask below or watch this 2-minute video explaining how wash sales work.

Top answer
1 of 3
1
Will selling FXAIX then buy VOO count?
2 of 3
1
So, I pretty much understand now what happened with my wash sale last year, when I sold the individual stock in my brokerage account from an ESPP and then the next quarter's purchase then happened within that window (obviously, I should have just let it ride instead of selling at a "loss" [less than FMV but still more than discounted price]). What is confusing me though is how it's being reported on the 1099-B? From looking at my transaction history it's as follows: Date | Action | "as of" | appx price | Shares | Total Shares | 1/4/23 | bought | 12/30/22 | $35 | 44 | 44 | 4/3/23 | bought | 3/31/22 | $27 | 57 | 101 | 4/10/23 | sold | $29 | 23 | 78 | 4/12/23 | sold | $30 | 23 | 55 | 4/26/23 | sold | $29 | 55 | 0 | 7/5/23 | bought | 6/30/23 | $23 | 68 | 68 | 7/5/23 | sold | $26 | 68 | 0 | 10/2/23 | bought | 9/29/23 | $24 | 67 | 67 | 10/5/23 | sold | $25 | 67 | 0 Again, I don't even recall how/why I sold in those lot sizes in April, other than I realized I forgot to try to do a "same day sale" of the lot purchased in January and the purchase from April was just about settling around that same time. (I may have done some sort of limit instead of market sale.) Regardless, the 1099-B shows different sale dates and lot sizes? Date Sold | Date Acquired | Shares | Notes | 4/10/23 | 12/30/22 | 23 | Wash Sale Loss Disallowed | 4/12/23 | 12/30/22 | 21 | Wash Sale Loss Disallowed | 4/12/23 | 12/30/22 | 2 | all 44 shares from 12/30 already accounted for above? | 4/26/23 | 12/30/22 | 21 | more phantom shares from that lot | 4/26/23 | 12/30/22 | 21 | more phantom shares from that lot | 4/26/23 | 3/31/23 | 13 | only 13 of the 57 shares from that lot | 7/5/23 | 6/30/23 | 68 | looks good | 10/5/23 | 9/29/23 | 67 | looks good So, I'm just trying to make sure I have this done correctly in my taxes, and I guess the totals probably work out and that's most important (and I did adjust the bases of each to account for the ESPP discount). Are the oddities in the 1099-B in regards to the lots sold because of my accidental wash sale, and/or something that I need to correct on my taxes? As it stands, it looks like I sold 88 shares of a 44 share lot, and 13 of a 57 share lot, instead of 44/44 and 57/57. In the future, I'll make sure to do the ESPP sale every quarter as close as possibly to same-day (timing seems to vary by a couple of days, generally, as to when the shares actually settle into the brokerage account which makes it tricky to remember to check every day for a 3-4 day period each quarter).
🌐
Williamson Herald
williamsonherald.com › features › business › financial-focus-is-this-a-good-year-for-tax-loss-harvesting › article_851c24fa-5e3d-4670-a0e9-1c232e022df2.html
Financial focus: Is this a good year for tax-loss harvesting? | Business | williamsonherald.com
December 6, 2025 - This rule prevents you from claiming a loss if you, or your spouse or a related party, repurchase the same or a "substantially identical" investment within 30 days before or after the sale.
🌐
U.S. News
money.usnews.com › investing › term › wash-sale
Wash Sale Definition | Investing Dictionary | U.S. News
December 11, 2023 - The purpose of the wash sale rule is to prevent investors from selling a stock to gain the tax advantages and then immediately buying back into the position to essentially maintain their original investment.
🌐
FasterCapital
fastercapital.com › startup-topic › Wash-Sale-Rule.html
Wash Sale Rule - FasterCapital
On the other hand, the wash sale rule is a regulation that prevents investors from claiming a loss on the sale of an asset and then immediately repurchasing the same or a substantially identical asset.
🌐
Cornell Law School
law.cornell.edu › lii › wex › wash sale
wash sale | Wex | US Law | LII / Legal Information Institute
A wash sale is defined as the sale of an asset, such as stocks or bonds, at a loss, followed by the repurchase of the same or substantially similar asset within 30 days before or after the sale.
🌐
Bottom Line, Inc.
bottomlineinc.com › financial › taxes › what is a wash sale?
What Is a Wash Sale? - Bottom Line, Inc.
October 21, 2025 - Any purchase of a stock or of a “substantially identical” stock either 30 days before or 30 days after you’ve sold it for tax loss harvesting is considered a wash sale. Note: This rule applies not only to straight stocks but also to exchange-traded funds (ETFs) and mutual funds.
🌐
SD Mayer
sdmayer.com › resources › wash-sale-rule-for-investors
Understanding the Wash Sale Rule for Investors
September 23, 2025 - The wash sale rule, regulated by the IRS, states that if you sell a stock or security at a loss, you cannot repurchase the same or a substantially identical investment within 30 days before or after the sale date.