There are capital gains due on any profits made, and the US government (and others around the world) is getting more proactive in establishing guidelines. I could not find an official document, but these links might help. The first is a news article, and the second is a tax service which is linked at the bottom of the first article.
https://www.cnbc.com/2018/01/30/cryptocurrency-and-taxes-what-you-need-to-know.htmlhttps://bitcoin.tax/At this point I would, at the very least, be keeping meticulous records of all of your cryptocurrency transactions in preparation for reporting. Always best to be prepared, especially when it comes to taxes. Best general advice is to hold for at least a year when possible (and monetarily worthwhile!), as this greatly reduces the amount of capital gains tax payable. Either way, best to get ahead of the game, keep records and put aside enough profits to cover any gains, remembering to keep track of any losses too.
