Wash Sale Checker
Your broker only catches wash sales inside one account. Paste or upload your trades from every account, including a spouse's and your IRAs, to find the losses you cannot take this year, the basis to carry forward, and the date it is safe to buy back.
Federal rules under IRC 1091. Your trades are read in your browser and never uploaded, saved or put in a link. For education only, not tax advice.
Your trades, all accounts
One row per buy or sell, from every account you and your spouse hold, including IRAs. Columns: date, account, type (taxable, spouse, IRA or Roth IRA), action, symbol, quantity, price. The sample shows two wash sales.
Read in your browser only; nothing is uploaded or saved, and trades are never put in a link. 8 trades read.
2 wash sales found
$6,300
of losses cannot be taken this year. $4,500 moves into the basis of the shares you bought back, and $1,800 is lost for good because the replacement was bought in an IRA.
Net gain or loss sold
−$7,500
before wash sales
Deferred to new shares
$4,500
Form 8949 code W
Lost for good (IRA)
$1,800
no basis increase
Shares now carrying a disallowed loss
- 100 VTI in Brokerage B, bought Feb 20, 2026
- basis $63.00/share, held from Oct 16, 2025
- 120 VTI in Brokerage A, bought Mar 25, 2026
- basis $59.00/share, held from Nov 18, 2025
- 40 QQQ in Brokerage A, bought Jul 1, 2026
- basis $195.00/share, held from Dec 17, 2025
How this is worked out. A loss is a wash sale if you, or your spouse, bought the same ticker within 30 days before or after the sale, in any account. The disallowed loss is added to the cost of the shares bought back and their holding period runs from the sold shares'; if they were bought in an IRA, the loss is gone for good. Your broker only reports wash sales inside one account.
Every sale
| Sale | Gain or loss | Disallowed | Allowed now | Replaced by |
|---|---|---|---|---|
| 300 VTIMar 10, 2026 · Brokerage A | −$4,500 | $3,300 | −$1,200 | 100 bought Feb 20, 2026 in Brokerage B (+$15.00/share)120 bought Mar 25, 2026 in Brokerage A (+$15.00/share) |
| 100 QQQJun 15, 2026 · Brokerage A | −$3,000 | $3,000 | $0 | 60 bought Jun 1, 2026 in Roth IRA (IRA: loss lost)40 bought Jul 1, 2026 in Brokerage A (+$30.00/share) |
On Form 8949, report each wash sale with code W in column (f) and the disallowed amount as a positive adjustment in column (g). Where your broker already reported a wash sale inside one account, check its figure against this one.
Same ticker is treated as substantially identical; different funds tracking the same index, options and short sales are not covered. Lots are sold first-in, first-out within each account. Shares bought and sold before the losing sale are not treated as replacements.
Thirty days both ways
The window is 30 days before and 30 days after the losing sale. Shares bought the week before you sell, including a dividend reinvestment, can make the loss a wash sale.
Your 1099-B misses most of them
Brokers report only same-account, same-securitywash sales. A repurchase at another broker, in a spouse's account or in an IRA is yours to find and report with code W.
IRA repurchases cost the most
A replacement bought in an IRA or Roth IRA disallows the loss with no basis increase to recover it later. The loss is simply lost.
Postponed, not forfeited
In a taxable account the disallowed loss is added to the cost of the new shares, and their holding period starts from the old shares'. You get the loss back when you sell them.
Frequently asked questions
What is a wash sale?
Selling a stock or fund at a loss and buying the same or a substantially identical security within 30 days before or after the sale, a 61-day window. The loss is not lost: it is added to the cost of the shares you bought back, and their holding period includes the time you held the shares you sold. The tax benefit is postponed until you sell the replacement shares.
Does my broker catch every wash sale?
No. Brokers must report a wash sale only when the sale and the repurchase happen in the same account with the same security (CUSIP). A repurchase at another broker, in your spouse's account or in your IRA is not on your 1099-B, but it still makes the loss a wash sale. You report those yourself on Form 8949 with code W.
What happens if I buy back in my IRA or Roth IRA?
The loss is disallowed, and because the replacement shares are inside the IRA, there is no basis to add it to. The IRS says in Revenue Ruling 2008-5 that the loss is simply gone. It is the most expensive kind of wash sale, and it often happens through automatic dividend reinvestment or a regular IRA contribution buying the same fund.
Does a purchase by my spouse count?
Yes. IRS Publication 550 says that if you sell at a loss and your spouse buys substantially identical stock within the window, you have a wash sale. That applies whether or not you file jointly. There is no official rule on whose shares then get the basis increase; the checker adds it to the shares your spouse bought.
When can I buy back without a wash sale?
On the 31st day after the sale. A purchase on day 30 is still inside the window. Remember the window also runs backward: shares bought in the 30 days before a losing sale count, including dividend reinvestments.
Are two S&P 500 funds substantially identical?
There is no IRS ruling. Shares of the same company or the same fund clearly are; stocks of two different companies generally are not. Funds from different providers tracking the same index are an open question, and practice varies. This checker treats only the same ticker as identical, so decide the close cases yourself.
Sources and references
- 26 U.S.C. 1091: loss from wash sales of stock or securities
- Treas. Reg. 1.1091-1: matching rules for replacement shares
- Treas. Reg. 1.1091-2: basis of replacement shares, with examples
- IRS Rev. Rul. 2008-5: a repurchase in an IRA or Roth IRA disallows the loss for good
- IRS Publication 550: wash sales, including purchases by a spouse
- IRS Form 1099-B instructions: brokers report only same-account, same-CUSIP wash sales
- IRS Form 8949 instructions: code W and the disallowed amount
- Rules encoded as of 27 October 2026.
Disclaimer: This checker is for educational purposes only and does not constitute tax advice. It treats the same ticker as substantially identical, sells lots first-in, first-out, and leaves out options, short sales and corporate actions. Check the results against your broker statements and a tax professional before filing.
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