Offer your thoughts or opinion on the input financial query or topic using your financial background.

When and how should I pay taxes on ForEx trades?
Legally speaking, when you convert that bit-coin onto something else, the Israeli Tax Authority will look into the value of that something else, compare it to the original value of the previous something else you used to buy bit-coins (USD, in your example), and charge you capital gain taxes for the difference. According to the Israeli law you're supposed to pay taxes when selling (converting the bit-coin to something else), and since you're not using any formal bank or stock broker which will automatically deduct the taxes, you have to pay the taxes yourself. By not doing so you're committing a tax fraud. The real question you're asking is whether they'll come after you. Well, that depends on the amounts. They might. Pay attention: there's no statute of limitation for tax fraud in Israel. They may come after you in 50 years from now. Another thing to keep in mind: if you used bit-coins to buy something (services or products of any kind), you probably didn't pay the VAT (מע"מ) - which is another case of tax fraud on your behalf. PS: I'm not a lawyer or accountant, so get a professional advice, but I have been dealing with the Tax Authority in Israel, so I've got a pretty good idea of what the rules are.