Hi.
i didn't traded so much of my crypto for FIAT so i didn't dealt with that question yet.
however i think it's an issue need to be dealt with.
1. do you use accounting services?
2.if so, do you keep documentation of all traded or bought coins?
3. what do you do in cases of profit from ICO's
WHAT SHOULD I DO??
it depends on which country you live in
for small amounts i dont think it is easy to understand if you did profit or not
but, all of a sudden if you stransfer 1 million usd to your account, for sure they will make you pay the tax if it is not a tax free country