A wash sale occurs when you sell or trade a security at a loss and purchase a “substantially identical” security within 30 days before or 30 days after that sale. The Internal Revenue Service (IRS) disallows the immediate deduction of that loss for tax purposes. The rule exists to prevent investors from claiming tax losses while effectively retaining the same market exposure.
Key points at a glance
– Window: 30 days before to 30 days after the loss sale (commonly described as a 61‑day span if you count the sale day).
– Effect: Disallowed loss is not lost forever — it is added to the cost basis of the replacement shares and the holding period of the sold shares tacks onto the new shares.
– Applies to: stocks, bonds, options, contracts, mutual funds, ETFs, and purchases in different accounts (including IRAs) or by related parties (e.g., spouse, controlled entity).
– Reporting: Disallowed wash sale loss is reported on Form 8949/Schedule D with an adjustment (code W). Brokers commonly report wash sales for a single taxable account on Form 1099‑B, but you are responsible for wash sales across accounts.
– Source IRS guidance: Publication 550, Topic No. 409, and Rev. Rul. 2008‑5.
How the rule works — mechanics and tax consequences
1. Sale at a loss: You sell shares of Security A and realize a loss.
2. Purchase within the wash-sale window: If you (or your spouse or a company you control) buy substantially identical shares within 30 days before or after that loss sale, the loss is disallowed for tax deduction in that tax year.
3. Basis adjustment: The disallowed loss is added to the cost basis of the newly purchased substantially identical shares. That raises your basis and reduces any future gain (or increases a future loss) when those replacement shares are eventually sold.
4. Holding period: The holding period of the original shares carries over to the replacement shares for purposes of determining long‑term vs. short‑term capital gain treatment.
Worked example (simple numbers)
– You bought 100 shares at $100 = basis $10,000.
– You sell 100 shares at $70 = sale proceeds $7,000 → realized loss $3,000.
– Within 30 days you buy 100 replacement shares at $70 = $7,000.
Result: The $3,000 loss is disallowed today and is added to the new shares’ basis: new basis = $7,000 + $3,000 = $10,000. When you later sell the replacement shares, that adjusted basis will determine the taxable gain or loss.
Common situations and special considerations
– “Substantially identical” is not precisely defined in statute. Shares of the same company are clearly substantially identical. Different funds that track the same index (e.g., S&P 500 ETFs from different issuers) are potentially at risk — IRS guidance is limited, so many advisors recommend treating them as risky within the wash-sale window.
– Options: Buying call options or writing puts that give equivalent exposure can trigger the rule if the option position is substantially identical to the stock position.
– Bonds/preferred stock: IRS ordinarily does not treat bonds or preferred stock as substantially identical to a company’s common stock, but convertible or virtually identical preferred issues can be problematic.
– IRAs and retirement accounts: Purchases of substantially identical securities in an IRA within the window will trigger the wash sale rule and permanently disallow the loss; you don’t get the loss now nor does the IRA’s basis get increased (Rev. Rul. 2008‑5).
– Related parties: Purchases by your spouse or certain entities you control can create wash sales.
– Dividend reinvestment plans (DRIPs): Automatic reinvestment of dividends may create purchases inside the 30‑day window and trigger wash-sale consequences.
Reporting a wash sale
– Brokers: Many brokers report wash sale adjustments for transactions executed within the same taxable account on Form 1099‑B, but they often do not coordinate across your different accounts (non‑retirement accounts vs. IRAs) or across accounts owned by your spouse. You are ultimately responsible for correct reporting.
– Tax forms: Report the details on Form 8949 and Schedule D. Enter the disallowed amount as an adjustment (use code W) and adjust the basis of the replacement shares accordingly. See IRS Publication 550 and Topic No. 409 for examples and instructions.
Is the window 30 or 60 days?
– The rule specifies 30 days before and 30 days after the sale. People commonly say “60‑day window,” but it’s more precise to say “30 days before OR after” the sale — if you include the sale day itself, it spans 61 days total (30 days prior + sale day + 30 days after).
Is it illegal to trigger a wash sale?
– No — wash sales are not illegal. The rule only disallows the immediate tax deduction of the loss. For some active traders, wash sales happen frequently and simply defer the recognition of the loss. However, they can produce unfavorable immediate tax outcomes and complicate recordkeeping.
Practical steps to avoid or manage wash sales
1. Plan a 31‑day buffer: If you want to claim a loss, avoid buying the same (or substantially identical) security for at least 31 days after the sale (and avoid having bought it in the 30 days before). This is the simplest and most certain way to avoid the rule.
2. Use non‑identical replacements: Replace a sold security with a different but correlated security (e.g., sell an S&P 500 ETF and buy a total‑market ETF or a different sector ETF) — but beware that very similar ETFs/funds may still be treated as substantially identical in some cases.
3. Harvest losses earlier in the year: Don’t wait until year‑end to do all tax‑loss harvesting; that reduces the need to repurchase quickly near December and reduces the risk of inadvertently triggering the rule.
4. Use tax‑aware funds or baskets: Some tax advisors use funds or baskets that provide similar exposure without being “substantially identical.” Document the differences.
5. Avoid replacement purchases in IRAs: Never repurchase substantially identical securities in an IRA within 30 days of a loss sale in a taxable account — that locks in a permanently disallowed loss (Revenue Ruling 2008‑5).
6. Consider a tax professional for active traders: Day traders and pattern day traders often create complex wash‑sale patterns across many trades and accounts; professional tax help and specialized software can help.
7. Recordkeeping and tracking: Keep detailed trade logs, watch 30‑day windows across all accounts and related-party accounts, and reconcile broker 1099‑B wash‑sale reporting with your own calculations. Brokers may not report wash sales that cross accounts.
8. If you trigger a wash sale intentionally: Understand that the loss is deferred (added to the basis of replacement shares) and prepare for the future tax implications.
Practical example: How to harvest safely (illustrative)
– Problem: You hold 100 shares of Fund A (loss) and want to preserve market exposure while harvesting the loss.
– Options:
a) Wait 31 days and repurchase Fund A.
b) Buy Fund B that tracks a broader index or uses a different issuer/fund structure — document why Fund B is not “substantially identical.”
c) Use inverse/other instruments cautiously — these may still trigger wash rules or introduce different risks.
– Choose the approach that matches your risk tolerance and consult a tax professional if uncertain.
Recordkeeping and tax filing checklist
– Track purchase and sale dates to identify 30‑day windows.
– Reconcile broker Form 1099‑B wash‑sale amounts with your own records. Brokers often provide wash‑sale adjustments only for that brokerage account.
– Report adjustments on Form 8949 (use Code W) and reflect the adjusted basis on Schedule D.
– Keep documentation of rationale if you use a replacement security that could be viewed as similar (e.g., different ETF with differing holdings).
When a wash sale might be acceptable
– Temporary exposure maintenance: If you need immediate exposure and don’t want to wait 31 days, you may accept the tax deferral knowing your loss is added to basis of the replacement. This is a strategic decision — not illegal — but changes timing of tax benefits.
– Active traders: For some traders, constant turnover and the administrative burden of avoiding wash sales may make accepting the deferred loss sensible. Consider trader tax status and consult a tax advisor.
Resources and IRS guidance
– IRS Publication 550, Investment Income and Expenses — wash sale rules and examples.
– IRS Topic No. 409, Capital Gains and Losses.
– Revenue Ruling 2008‑5 — wash sale interaction with IRAs and retirement accounts.
Bottom line
The wash sale rule denies an immediate deduction for losses when substantially identical securities are bought within 30 days before or after a loss sale. The disallowed loss is added to the basis of the replacement shares, deferring the tax benefit until a later sale. Careful planning (31‑day buffers, use of non‑identical replacements, and careful recordkeeping) and professional advice for complex situations can reduce unwanted tax outcomes and reporting headaches.
Editor’s note: The following topics are reserved for upcoming updates and will be expanded with detailed examples and datasets.