[Exitonly]

I'm pretty sure it's not when you 'cash it out' but when you earn it. Atleast that's what i've read anytime i've looked this stuff up.

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other general info:

you can file either as a professional (but you'll need lots and lots of records) and then you'll pay like a 15% self employment tax, and can deduct ISP costs and office supplies/books.

or

you can file it as gambling where you add all your winnings into your income, and you can deduct the losses. But you're supposed to winning sessions seperate from losing sections and it's crappy, so even if you were a losing player, as long as you had some winning sessions, you'd be paying taxes on it.

And as far as not paying them, that seems like a bad idea as the governent will probably eventually find out, and interest and penalties will suck dick.