Do I need to pay taxes if I sell an alt coin for bitcoin then rebuy a different alt coin. I never took out actual USD so I am unsure how that would work. Or am I only taxes on actual USD made when I cash out?
In most countries you will only be taxed on any USD you take out, quite simply, USD out - USD in = taxable amount, it is a little more complex than that and an accountant can work things out in detail for you but that's the simplified version.