Can a day trading taxable income be more than the actual capital gain?

External question — Personal Finance Stack Exchange Author: giorgijaparidzevillanovaedu Original post: https://money.stackexchange.com/questions/137935 License: CC BY-SA 4.0 — https://creativecommons.org/licenses/by-sa/4.0/ Adaptation: HTML converted to plain text; contact email addresses removed. I've day-traded (in USA) actively during 2020, mostly short trades. Never kept positions overnight, so carried no positions into 2021 (and, similarly, no positions were carried from 2019 into 2020. The cash in the account at the beginning of the year was $300,000, and was about $400,000 at the end of the year. Thus, the actual gain was $400,000-$300,000=$100,000. But my accountant is telling me that the taxable gain, according to form 1099, is $130,000 instead. Explains this discrepancy by some wash-sale rules, but it all appears so absurd that I cannot believe. Shall I assume an error somewhere, or is it really possible that I can be taxed on more than what my actual capital gain was? more info from the comments: the trades were commission-free. Even if not, the 30% difference is to big to be attributed to some hidden fees. no money was pulled in or out of the account