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Wash Sale Rule Explained: Complete Guide for Traders

The wash sale rule is one of the most important tax rules that every active trader needs to understand. Violating this rule can result in disallowed losses, unexpected tax bills, and headaches during tax season. In this comprehensive guide, we will explain exactly what the wash sale rule is and how to avoid triggering it.

What is the Wash Sale Rule?

The wash sale rule is an IRS regulation that prevents taxpayers from claiming a tax deduction on a security sold at a loss if they purchase a substantially identical security within 30 days before or after the sale. The rule applies to stocks, bonds, mutual funds, ETFs, and options.

The 61-Day Window: The wash sale rule applies to purchases made 30 days before the sale, the day of the sale, and 30 days after the sale. This creates a 61-day window where you must avoid buying substantially identical securities.

How the Wash Sale Rule Works

When you trigger a wash sale, the loss is not permanently lost. Instead, it gets added to the cost basis of the replacement shares. This defers the loss until you eventually sell those replacement shares without triggering another wash sale.

Example of a Wash Sale

You bought 100 shares of XYZ stock for $5,000. The stock drops and you sell all shares for $3,000, creating a $2,000 loss.

If you buy 100 shares of XYZ within 30 days at $32 per share ($3,200), the wash sale rule is triggered:

What Triggers a Wash Sale?

Several actions can trigger the wash sale rule:

What Does NOT Trigger a Wash Sale?

The wash sale rule has limits. These actions typically do not trigger a wash sale:

Substantially Identical Securities

The IRS does not provide a precise definition of "substantially identical," which creates some gray areas. Here are general guidelines:

Generally Substantially Identical

Generally NOT Substantially Identical

Wash Sales and Options

Options add complexity to the wash sale rule. Here is what you need to know:

Strategies to Avoid Wash Sales

Here are practical strategies to harvest losses without triggering wash sales:

Tax-Loss Harvesting Pair Example

You own Vanguard S&P 500 ETF (VOO) at a loss. To harvest the loss:

Note: The IRS has not definitively ruled on whether these are substantially identical. Consult a tax professional.

Wash Sales Across Multiple Accounts

A common misconception is that wash sales only apply within the same account. The wash sale rule applies across:

IRA Trap: If you sell a stock at a loss in your taxable account and buy it within 30 days in your IRA, the loss is disallowed AND you cannot add it to the IRA's cost basis. The loss is permanently lost.

Tracking Wash Sales

Your broker is required to track and report wash sales on your 1099-B, but only for transactions within that account. You are responsible for tracking wash sales across multiple accounts and between your accounts and your spouse's accounts.

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Common Wash Sale Mistakes

Avoid these common errors that trigger unintended wash sales:

Summary

The wash sale rule prevents you from claiming a tax loss if you buy substantially identical securities within 30 days before or after the sale. While the rule can be frustrating for active traders, understanding how it works allows you to plan your tax-loss harvesting strategy effectively. Remember that disallowed losses are not lost forever; they are added to your cost basis and can be claimed when you eventually sell without triggering another wash sale.

Ready to learn more about tax-efficient trading? Check out our guide on tax-loss harvesting strategies or learn about short-term capital gains taxes.