Considering at least Coinbase is US-based, you may want/need to look into compliance with the guidance[1]. The tl;dr is that you're supposed to mark to market f

Considering at least Coinbase is US-based, you may want/need to look into compliance with the guidance[1]. The tl;dr is that you're supposed to mark to market for each trade and denominate it in USD; if you're in the US and haven't been keeping records, I'd strongly consider retaining a tax professional for advice/service if you get one of these. I assume that the IRS isn't going to take your lack of records very seriously or kindly. [1]https://www.irs.gov/businesses/small-businesses-self-employed/virtual-currencies https://www.irs.gov/businesses/small-businesses-self-employe...