For me, it depends on the volume of transactions. The more transactions there are, the more likely I am to group them together.

While the purists would list each sell separately if they are shown separately on the 1099-B, I'll routinely group those by day. So if your sell order got split into multiple lots but all sold on the same day, I'll enter them as a single item. But if it got split into two days, then I'd split them up on the tax return.

Frankly, I don't get too worked up about it. The key is to make the total of the sales match the total of the 1099-Bs. And now we also need to make sure that all reported purchases match up to the 1099-Bs as well. If those two totals match, the IRS is highly unlikely to send the dreaded (but often quite wrong) matching notice, a CP2000.

And in any event, even in an audit, if your numbers are correct, there's nothing for the auditor to adjust.

--Peter