{"attribution":{"lines":["The wash-sale rule applied here is Internal Revenue Code section 1091, in the form IRS Publication 550 describes it (a US Government work in the public domain).","BasisScout is not affiliated with or endorsed by the IRS or by any broker."],"sources":[{"name":"Internal Revenue Code section 1091 and IRS Publication 550, Investment Income and Expenses (Wash Sales)","licence":"Public domain (U.S. Government work)","licence_url":"https://www.usa.gov/government-copyright","url":"https://www.irs.gov/publications/p550"}],"text":"The wash-sale rule applied here is Internal Revenue Code section 1091, in the form IRS Publication 550 describes it (a US Government work in the public domain).\nBasisScout is not affiliated with or endorsed by the IRS or by any broker."},"disclaimer":"BasisScout is a record-keeping calculation, not tax advice. It applies the US wash-sale rule (IRC section 1091) to the trades you send, using same-ticker matching only. It cannot see trades you did not send, cannot decide whether two different securities are \"substantially identical\", and does not know your full tax situation. Confirm results with a tax professional before relying on them. BasisScout is not affiliated with any broker or with the IRS.","examples":["https://basisscout.scalpstream.com/basis?trades=fid,taxable,2026-08-01,PLTR,buy,100,10;fid,taxable,2026-09-03,PLTR,sell,100,8\u0026check=buy\u0026symbol=PLTR\u0026on=2026-09-20","https://basisscout.scalpstream.com/basis?trades=fid,taxable,2026-06-01,PLTR,buy,100,10;roth,roth_ira,2026-09-10,PLTR,buy,50,11\u0026check=sell\u0026symbol=PLTR\u0026on=2026-09-20\u0026account=fid\u0026quantity=100"],"honesty":"Every answer is a rule calculation on the trades sent, in sentences that state the rule and never recommend a trade. It cannot see trades it was not sent, so 'no open window' means no window among those trades. Rows the rule cannot apply to (a sale of more than the account holds, an unsupported kind) are listed in errors, never dropped silently.","parameters":{"account":"check=sell: the account the shares would be sold from, as named in trades","account_type":"check=buy: where the purchase would be: taxable, trad_ira, roth_ira, spouse_taxable, spouse_ira (default taxable)","check":"buy or sell: the pre-trade question (optional; leave out for the ledger alone)","on":"the date of the proposed trade, YYYY-MM-DD (default: today)","quantity":"check=sell: how many shares","symbol":"the ticker the question is about (required with check)","trades":"your trades: rows account,account_type,date,symbol,kind,quantity,price[,fees] separated by ';', or a JSON array of objects with those fields (required)","year":"the tax year to total (default: the year of `on`, else of the latest trade)"},"payment":"x402 (HTTP 402): USDC on Base, USDC on Arbitrum, USDC on Polygon, USDC on Solana, XRP on the XRP Ledger, RLUSD on the XRP Ledger. Custody-free.","price_usd":"0.01","privacy":"The trades you send are processed in memory for this response only. They are not stored, not logged and not shared.","scope":"US federal wash-sale rule only, matched on the same ticker across every account sent (taxable, traditional and Roth IRA, spouse). Not modelled: options on the same underlying, short sales, stock splits, \"substantially identical\" pairs (share classes, similar ETFs) and digital assets, to which the rule does not currently apply. FIFO lot matching. Trade dates, not settlement dates.","service":"BasisScout","source":"Rule: Internal Revenue Code section 1091 and IRS Publication 550, Investment Income and Expenses (Wash Sales). The calculation is BasisScout's own.","what":"A machine-payable wash-sale check: send your own trades, ask whether buying or selling a ticker on a date would wash a loss, and get the rule's answer across every account you sent, taxable, IRA and spouse together, before the trade rather than on next year's 1099-B.","why":"A broker reports wash sales only inside one account for the identical security. Everything cross-account, cross-broker, in an IRA or in a spouse's account is the taxpayer's own job on Form 8949, and an IRA repurchase loses the loss for good. BasisScout applies IRC section 1091 to all the accounts at once: disallowed loss, the basis the replacement shares carry, the holding period that tacks on, the first safe rebuy date, and the year's realized figures split short and long term."}