What is the 30-day wash sale rule?

The 30-day wash sale rule states that if you sell a security at a loss and repurchase a "substantially identical" security within 30 days before or 30 days after the sale date, the IRS will disallow the tax deduction for that loss. This means the total window is 61 days, including the sale date itself.

Does the wash sale rule apply to mutual funds and ETFs?

Yes, the wash sale rule applies to mutual funds and ETFs. If you sell a fund at a loss and buy a "substantially identical" fund within the 61-day window, it's a wash sale. Funds tracking the exact same index are often considered substantially identical, while funds tracking different indexes or with different investment objectives generally are not.

How do I avoid a wash sale?

The simplest way to avoid a wash sale is to wait at least 31 days after selling a security at a loss before repurchasing the same or a substantially identical security. Alternatively, you can immediately buy a different, non-substantially identical security to maintain market exposure.

Does the wash sale rule apply to IRAs or 401(k)s?

Yes, the wash sale rule applies across all your accounts, including IRAs and 401(k)s. If you sell a security at a loss in a taxable account and repurchase a substantially identical security in an IRA or 401(k) within the 61-day window, the loss is disallowed and cannot be added to the basis of the shares in the retirement account, effectively making the loss permanently lost for tax purposes.

What happens if I trigger a wash sale?

If you trigger a wash sale, the disallowed loss is added to the cost basis of the newly acquired, substantially identical security. This defers the recognition of the loss until the new security is sold in a non-wash sale transaction. If the repurchase is in a retirement account, the loss is permanently disallowed.

How do I report a wash sale on my taxes?

Your brokerage firm will typically report wash sales that occur within the same account on Form 1099-B. You must then report the adjustment on Form 8949 and Schedule D. For wash sales across different accounts or brokerages, you are responsible for tracking and manually making the necessary adjustments to your cost basis and reporting them to the IRS.

Is it a wash sale if my spouse buys the same stock?

Yes, the wash sale rule applies to you and your spouse. If you sell a security at a loss and your spouse repurchases a substantially identical security within the 61-day window, it is considered a wash sale. The disallowed loss would be added to the cost basis of the shares in your spouse's account.

Wash Sale Rule: Complete Tax Guide for Investors | One…

Last Updated: August 6, 2026

Wash Sale Rule: Complete Taxes Guide for Investors Have you ever sold an investment at a loss, only to repurchase it shortly after, assuming you could claim that loss on your taxes? Many investors make this common mistake, often unknowingly running afoul of the IRS's wash sale rule. This seemingly straightforward tax regulation can turn what you thought was a savvy tax-loss harvesting strategy into a costly error, disallowing your capital loss and potentially increasing your tax bill. Understanding the wash sale rule is not just about avoiding penalties; it's about optimizing your investment strategy and ensuring you accurately report your gains and losses to the IRS. This comprehensive guide will demystify the wash sale rule, explaining its purpose, how it works, and its far-reaching implications for your investment portfolio and tax planning. We'll dive into the specifics of what triggers a wash sale, the 30-day window, and how it

applies to various securities and accounts. By the end of this article, you'll have a clear understanding of how to navigate this complex rule, allowing you to harvest losses effectively and keep more of your hard-earned money. > Wash Sale Rule Definition: The wash sale rule, enforced by the IRS, disallows an investor from claiming a tax deduction for a capital loss on the sale of a security if they repurchase the "substantially identical" security within 30 days before or after the sale date. What is the Wash Sale Rule and Why Does it Exist? The wash sale rule is a critical component of the U.S. tax code designed to prevent investors from artificially creating tax losses without truly changing their investment position. Without this rule, an investor could sell a stock at a loss, immediately buy it back, and claim a tax deduction while maintaining continuous ownership of the

asset. This would undermine the integrity of the capital gains and losses system. Preventing Abusive Tax-Loss Harvesting The primary purpose of the wash sale rule is to prevent abusive tax-loss harvesting. Tax-loss harvesting is a legitimate strategy where investors sell investments at a loss to offset capital gains and, potentially, a limited amount of ordinary income (up to $3,000 annually). This can significantly reduce an investor's tax liability. However, the IRS wants to ensure that when you claim a loss, you've genuinely divested from the asset for a meaningful period. The rule, enshrined in Internal Revenue Code Section 1091, ensures that a loss is only recognized for tax purposes if there's a genuine economic change in the investor's position. If you sell a stock at a loss and then quickly buy it back, the IRS views this as if you never truly exited the position. Therefore, the loss is disallowed.

The 30-Day Window: Before and After The core of the wash sale rule revolves around a 61-day window. This period includes the sale date, plus 30 days before the sale, and 30 days after the sale. If you sell a security at a loss and then, within this 61-day window, you (or your spouse, or a company you control) buy, agree to buy, or acquire an option or contract to buy "substantially identical" stock or securities, a wash sale occurs. It's crucial to understand that the 30-day period applies both before and after the loss-generating sale. For example, if you buy a stock on January 1st, sell it at a loss on January 15th, and then buy it back on February 1st, that's a wash sale. Similarly, if you buy a stock on January 1st, sell it at a loss on February 15th, and then buy it back on March

1st, that's also a wash sale. The rule is designed to catch both pre-emptive purchases and immediate repurchases. How the Wash Sale Rule Works in Practice When a wash sale occurs, the disallowed loss is not simply lost forever. Instead, it is added to the cost basis of the newly acquired, substantially identical security. This adjustment effectively defers the recognition of the loss until the new security is sold in a non-wash sale transaction. Adjusting the Cost Basis Let's illustrate with an example of cost basis adjustment. Suppose you bought 100 shares of Company X for $50 per share. Later, you sell those 100 shares for $40 per share, incurring a $1,000 loss ($50 $40 = $10 loss per share 100 shares). Within the 30-day window, you buy back 100 shares of Company X for $42 per share. Because of the wash sale rule, you cannot claim the $1,000 loss