Do Stock Brokers Catch Every Wash Sale? (w/Examples) + FAQs

This article reflects federal rules and state rules as of June 2026 and covers tax year 2025 (filing in 2026) and tax year 2026. Tax law changes — confirm current figures before you file.

Quick Answer

No. For tax year 2025, your broker only catches wash sales inside a single account for the same security (CUSIP). Brokers do not track wash sales across different brokers, between your taxable and IRA accounts, or between you and your spouse. You must track those yourself.

A broker’s Form 1099-B can look complete and still be wrong, because the law only forces your broker to watch one account at a time. When you sell a stock at a loss and buy it back too soon somewhere your broker can’t see, the loss still gets disallowed — but the Form 1099-B won’t show it. The IRS still expects you to report it correctly.

This gap matters because the responsibility lands on you, not your brokerage. The IRS notes that the wash sale rule applies to all of your accounts and even your spouse’s, while broker reporting under IRS regulations is limited to identical securities in one account. According to a 2025 CPA analysis on LinkedIn, most investors simply trust the broker statement, which “may not be correct every time.”

🔍 You’ll learn exactly which wash sales your broker catches — and the four kinds it misses.
💸 You’ll see worked dollar examples so you can copy the math for your own trades.
🧾 You’ll get a step-by-step Form 8949 and Schedule D walkthrough with the “W” code.
⚠️ You’ll avoid the seven mistakes that trigger IRS notices and lost deductions.
🪙 You’ll find out why crypto escapes the rule in 2025 — and what may change.

What a Wash Sale Actually Is

A wash sale happens when you sell a stock or security at a loss and buy the same or a “substantially identical” security within 30 days before or after that sale. Because the window runs both directions, the full danger zone is 61 days: 30 days before the loss sale, the sale day itself, and 30 days after. The rule lives in Section 1091 of the tax code, and it exists to stop investors from claiming a tax loss while keeping the same investment position.

When the rule triggers, the IRS does not let you delete the loss forever in a normal taxable account. Instead, your disallowed loss gets added to the cost basis of the replacement shares, and the old holding period carries over. You don’t lose the deduction permanently — you defer it until you sell the replacement shares for good. The consequence of ignoring it is real: you claim a loss this year, the IRS disallows it, and you owe back tax plus interest and possible penalties.

Here is a plain example of the mechanics. Say you buy 100 shares of a stock for $5,000, sell them for $3,500 (a $1,500 loss), then rebuy 100 shares for $3,600 within 30 days. The $1,500 loss is disallowed for now. Instead, it attaches to your new shares, making their basis $3,600 + $1,500 = $5,100. A common misconception is that the loss vanishes — it doesn’t, in a taxable account; it just waits. What to do: flag any repurchase inside the 61-day window and adjust your basis before you file.

How Brokers Catch Wash Sales (and the Rule They Follow)

Brokers must report wash sales on Form 1099-B, but only within a narrow lane set by IRS regulations. A broker is required to identify and report a wash sale only when both the loss sale and the repurchase happen in the same account and involve the exact same security, matched by its CUSIP number. That single-account, identical-CUSIP standard is the whole job the law gives them.

This is narrower than the law you must follow. The actual wash sale rule under Section 1091 covers all your accounts, your spouse’s accounts, your IRAs, and “substantially identical” securities — not just identical ones. As Arthat Taxes explains, “by law, brokers are only required to report a wash sale on Form 1099-B if both the loss sale and the repurchase occur in the same account.” So the broker’s view and the law’s view do not match.

The consequence of trusting only the 1099-B is that you may file a return that looks clean but understates your disallowed losses. GreenTraderTax has long warned investors not to rely solely on 1099-Bs for wash sale adjustments. A common misconception is that the IRS “already has the right numbers from my broker.” What to do: treat the 1099-B as a starting point, then layer in trades your broker never saw.

The Four Wash Sales Your Broker Misses

Your broker’s blind spots fall into four main buckets, and each one can quietly disallow a loss you thought was safe. Knowing them is the difference between a correct return and an IRS notice. The table below shows the most common gaps.

Where the wash sale hides	Why your broker misses it
Two different brokerages (e.g., Fidelity loss, Schwab rebuy)	Each broker only sees its own account, so neither reports the match
Taxable account loss + IRA or Roth rebuy	The IRA is a separate “person/account”; the loss is also permanently lost
Your sale + your spouse’s purchase	Spousal accounts count as you, but no broker links them
Same security, different brokers via transfer	Cost basis can move, but wash sale flags often do not follow cleanly

Different brokers, same stock

When you sell a stock at a loss at one broker and rebuy it at another within 30 days, the wash sale rule still applies — but neither broker can see the other’s trades. The Bogleheads community confirms the “wash sale rule applies across brokers and across accounts.” Neither 1099-B will show the disallowance, so the math is on you. The consequence: an audit can disallow the loss years later, with interest. What to do: keep one master spreadsheet of all trades across every broker.

Taxable loss, IRA repurchase

This is the worst-case blind spot. Under IRS Revenue Ruling 2008-5, if you sell at a loss in your taxable account and your IRA or Roth IRA buys the same security inside the window, the loss is disallowed and your IRA basis is not increased. As Fidelity explains, this means the loss is “effectively forfeited, not deferred.” You lose it forever. What to do: never repurchase a recently-sold loser inside any IRA you control.

Spouse’s account

The rule treats you and your spouse as one taxpayer for wash sales, even when you file jointly through separate brokerages. If you sell at a loss and your spouse buys the same security within 30 days, the loss is disallowed. No broker connects the two accounts, so the flag is invisible. The consequence is the same deferred-loss adjustment, but it’s easy to trip by accident. What to do: coordinate trades with your spouse around any loss-harvesting move.

“Substantially Identical” — The Judgment Call Brokers Skip

Brokers only match the exact same security by CUSIP, but the law disallows losses on “substantially identical” securities too. The IRS has never published a bright-line test, so it comes down to “facts and circumstances,” as Morningstar explains. Two S&P 500 index funds from different companies are usually treated as not identical, while the same company’s common stock is always identical to itself.

This matters because a broker will never flag a “substantially identical” wash sale — it’s a legal judgment, not a CUSIP match. If you sell one S&P 500 ETF at a loss and buy a different issuer’s S&P 500 ETF the next day, most advisors treat that as safe, but aggressive cases can draw IRS scrutiny. Options and warrants on a stock can also count as substantially identical to the stock. A common misconception is that swapping ticker symbols always avoids the rule. What to do: when harvesting losses, switch to a fund that tracks a different index, not just a different brand of the same index.

Worked Example: A Cross-Broker Wash Sale

Let’s run the full math so you can copy it. Maria holds 200 shares of a tech stock at Broker A with a cost basis of $12,000. In November 2025 she sells all 200 shares for $9,000, locking in a $3,000 loss she plans to deduct.

Twelve days later, Maria buys 200 shares of the same stock at Broker B for $9,200, because she still believes in the company. Broker A reports a clean $3,000 loss on its 1099-B. Broker B reports nothing unusual, because it never saw the loss sale. On paper, Maria thinks she has a $3,000 deductible loss.

In reality, the wash sale rule disallows the entire $3,000. That disallowed loss is added to her Broker B shares, raising their basis from $9,200 to $12,200. Maria’s correct 2025 return shows a $0 deductible loss now — and a larger future loss when she finally sells the Broker B shares. If she instead claims the $3,000 and the IRS catches it, she could owe roughly $450 in extra federal tax at a 15% capital-gains rate, plus interest. What to do: Maria should report the wash sale on Form 8949 with code “W” and adjust her basis.

Worked Example: The IRA Loss Trap

David sells 100 shares of a stock in his taxable account for a $2,000 loss in March 2026. Eight days later, his Roth IRA buys 100 shares of the same stock. Because the IRA counts as David himself, this is a wash sale.

Here is the painful part. Under Revenue Ruling 2008-5, David’s $2,000 loss is disallowed and his Roth IRA basis is not increased. Unlike a normal wash sale, the loss is gone for good — it cannot attach to the IRA shares and resurface later. David permanently forfeits a $2,000 deduction, costing him as much as $440 in federal tax at a 22% ordinary bracket if those losses were offsetting ordinary income through the $3,000 allowance. What to do: keep loss-harvesting trades and IRA buys in completely separate securities.

Which Situation Applies to You?

Use this quick branch to find your risk level. The right answer depends on how and where you trade.

Your situation	Where to focus
One account, one broker, no rebuys	Your 1099-B is likely correct; verify and file
Multiple brokers or accounts	Build a master trade log; the broker misses cross-account matches
You trade in both taxable and IRA	Highest danger — IRA wash sales forfeit the loss permanently
You and your spouse both trade	Coordinate trades; spousal buys trigger the rule
You only trade crypto	Wash sale rule does not apply in 2025 (see below)

If you fall into the bottom four rows, do not rely on your broker’s numbers alone. If you’re in the top row and never rebought a loser within 61 days, your 1099-B is usually safe to file as-is.

Crypto: The Big Exception in 2025

Crypto is not subject to the wash sale rule for tax year 2025. Because the IRS treats cryptocurrency as property, not as a “stock or security,” Section 1091 does not apply. You can sell Bitcoin at a loss and rebuy it the next day and still deduct the loss today.

This is a powerful, legal tax-loss-harvesting edge, but it is not permanent. As a CPA analysis notes, the new Form 1099-DA digital-asset reporting is rolling out, and Congress has repeatedly proposed extending wash sale rules to crypto. The IRS has not finalized any crypto wash sale rule, so treat this as unsettled. A common misconception is that crypto is “tax-free” to trade — losses are deductible, but gains are still taxable. What to do: harvest crypto losses now if it fits your plan, but watch for law changes after 2025.

How to Report a Wash Sale: Form 8949 and Schedule D

When you catch a wash sale your broker missed, you fix it on Form 8949, then carry totals to Schedule D. Short-term sales (held one year or less) go in Part I; long-term in Part II. Following our guide to filling out Form 8949 keeps the entries clean.

Here is the step-by-step process. Each step has a real consequence if you skip it.

List the loss sale in Part I or Part II with your proceeds in column (d) and cost basis in column (e).
Enter code “W” in column (f) to mark it as a nondeductible wash sale loss, per the H&R Block walkthrough.
Enter the disallowed loss as a positive number in column (g), the adjustments column.
Make sure column (h) gain/loss now reflects the reduced or zeroed loss.
Carry your subtotals to Schedule D lines 1 and 8, separating wash-sale and non-wash-sale totals as the TurboTax community describes.
Add the disallowed loss to the basis of your replacement shares in your own records.

The deadline is your normal return due date — April 15, 2026, for tax year 2025, or October 15, 2026, with an extension. Missing the adjustment can trigger an IRS CP2000 notice when their data doesn’t match yours. What to do: reconcile every 1099-B against your own trade log before filing.

Does Your State Follow the Wash Sale Rule?

For federal purposes, the wash sale rule is set by Section 1091. Most states with an income tax start from your federal adjusted gross income or federal capital gains, so they automatically follow the federal wash sale treatment. That means a disallowed loss on your federal return is usually disallowed on your state return too.

A handful of states have no personal income tax at all — including Florida, Texas, Washington, Nevada, South Dakota, Wyoming, Alaska, and Tennessee — so the wash sale rule simply does not affect a state filing there, because there is no state tax on capital gains to begin with. New Hampshire taxes only certain investment income. The consequence of assuming your state matches federal is small in most cases, but states occasionally diverge on timing or conformity dates. What to do: confirm your state’s conformity on your state revenue agency page before filing, since state rules vary.

Mistakes to Avoid

Each of these errors has a direct cost, from lost deductions to IRS notices.

Trusting the 1099-B as complete — it misses cross-account wash sales, so you under-report disallowed losses.
Rebuying a loser in your IRA — the loss is forfeited permanently under Rev. Rul. 2008-5, not just deferred.
Forgetting your spouse’s trades — a spousal repurchase triggers the rule and surprises you at audit.
Ignoring the 30-day-before window — buying first, then selling at a loss, still counts, costing you the deduction.
Assuming different tickers are safe — substantially identical securities are disallowed, even with a new symbol.
Counting dividend reinvestment as innocent — an auto-reinvested purchase can trigger a small wash sale you never noticed.
Skipping the basis adjustment — you lose track of the deferred loss and overpay tax when you finally sell.

Do’s and Don’ts

Do keep a single master log of every trade across all brokers and accounts — it’s your only complete record.
Do wait at least 31 days before repurchasing a security you sold at a loss — it cleanly avoids the rule.
Do swap into a different-index fund when harvesting losses — it sidesteps “substantially identical” risk.
Do reconcile each 1099-B against your records — it catches the wash sales brokers can’t see.
Do turn off automatic dividend reinvestment around a loss sale — it prevents accidental triggers.
Don’t rebuy a loss security in any IRA you control — the loss disappears forever.
Don’t let your spouse buy what you just sold at a loss — the IRS treats you as one person.
Don’t assume crypto rules will stay loss-friendly — the law may change after 2025.
Don’t report only what the 1099-B shows when you traded across brokers — you’ll under-report.
Don’t guess on “substantially identical” — when unsure, pick a clearly different investment.

Pros and Cons of Relying on Your Broker

Upside of broker tracking	Downside of broker tracking
Free, automatic for single-account same-security trades	Blind to cross-broker and cross-account wash sales
Pre-filled 1099-B saves data entry at tax time	Misses IRA and spousal wash sales entirely
Matches what the IRS receives for that one account	Ignores “substantially identical” judgment calls
Reliable for buy-and-hold investors with one account	Can lull active traders into under-reporting
Reduces obvious errors on simple returns	Leaves you legally responsible for the gaps

The takeaway is that broker tracking is genuinely helpful for simple, single-account investors, but it is dangerous to lean on if you trade across multiple accounts or with a spouse.

What to Do Next

Take these steps in order before you file your tax year 2025 return.

Download every 1099-B from all your brokers for 2025.
Build one combined spreadsheet of all sales and repurchases, including IRA and spousal accounts.
Flag any repurchase within 30 days before or after a loss sale.
Mark each wash sale on Form 8949 with code “W” and adjust the basis.
Carry totals to Schedule D and file by April 15, 2026.
If you have heavy trading, IRA overlap, or “substantially identical” questions, hire a CPA — expect roughly $300 to $800 for a return with active trading, which often pays for itself in saved deductions.

This article is educational and not a substitute for advice from a licensed tax professional for your specific situation. A return with cross-account trading, IRA wash sales, or large losses is complex enough to warrant a CPA or tax attorney.

FAQs

Do brokers report wash sales between two different brokers?

No. For tax year 2025, each broker only sees its own accounts. A loss at one broker and a rebuy at another is still a wash sale, but neither 1099-B will report it. You must track it yourself.

Does the wash sale rule apply across my IRA?

Yes. Under Revenue Ruling 2008-5, a taxable-account loss plus an IRA or Roth repurchase is a wash sale. Worse, the loss is permanently forfeited and your IRA basis is not increased.

What is the wash sale time window?

61 days total. The window covers 30 days before the loss sale, the sale day, and 30 days after, per IRS Publication 550. Buying inside that window in either direction triggers the rule.

Does the wash sale rule apply to crypto?

No, not for 2025. The IRS treats crypto as property, so Section 1091 does not apply. You can sell crypto at a loss and rebuy it immediately, though Congress may change this after 2025.

What happens to my disallowed wash sale loss?

It’s added to your replacement shares’ basis in a taxable account, deferring the loss until you sell. But in an IRA repurchase, the loss is lost forever.

Does the wash sale rule apply to my spouse’s account?

Yes. The IRS treats married taxpayers as one for this rule. If you sell at a loss and your spouse rebuys the same security within 30 days, the loss is disallowed even across separate brokers.

How do I report a wash sale on my taxes?

On Form 8949 with code “W.” Enter the disallowed loss as a positive number in column (g), then carry totals to Schedule D. Adjust your replacement shares’ basis in your records.

Are two different S&P 500 ETFs substantially identical?

Usually no. Different issuers tracking the same index are generally treated as not identical, per Morningstar. But the IRS uses a facts-and-circumstances test, so it isn’t guaranteed.

Can dividend reinvestment trigger a wash sale?

Yes. An automatic reinvested purchase within 30 days of a loss sale counts as a repurchase and can trigger a partial wash sale. Turn off reinvestment around loss-harvesting trades to avoid it.

Will the IRS catch a wash sale my broker missed?

Sometimes. The IRS may not flag it immediately, but cross-account wash sales can surface in an audit, leading to disallowed losses, back tax, and interest. You remain legally responsible for reporting them.

Does my state follow the federal wash sale rule?

Usually yes. Most income-tax states start from federal income, so they follow Section 1091. No-income-tax states like Florida and Texas don’t tax capital gains at all, so the rule has no state effect.

Is the wash sale window 30 days or 61 days?

61 days in total. People say “30 days,” but the rule runs 30 days before and 30 days after the loss sale, plus the sale day itself, for a 61-day danger zone.

Word count: approximately 2,950.

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