Originally Posted by dakota-xx
And how would the IRS define professional poker player?
From what I have read, there is no "definition". The IRS makes the determination on a case by case basis, but the bar is pretty high. According to the IRS "Like any other taxpayer, a gambler has the burden of proving that his activities rise to the level of a trade or business."
Reading the cases are tortuous, but if you are not engaged in gambling primarily full time and it is not your primary source of income and you don't have substantial per session records, it seems unlikely the IRS will buy that you are a professional gambler. Just my opinion, of course, don't want to get arrested for giving tax advice.
And if you are considered a professional and profitable, the downside appears to be that you have to pay self-employment tax of 13.3% for 2012 (10.4% for Social Security and 2.9% for Medicare).