Free wash-sale calculator

Paste trades, one per line: date, buy or sell, symbol, shares, price. Add , ira to a buy made in an IRA. Nothing is stored.

The rule in one paragraph

If you sell at a loss and buy the same (or substantially identical) security within 30 days before or after the sale, in any of your accounts, the loss is disallowed for now and added to the basis of the new shares, whose holding period starts from the old shares' purchase. If the buy is in an IRA, the loss is gone for good (Rev. Rul. 2008-5). Your broker's 1099-B only catches wash sales inside that one account.