With all the excitement and opportunities around cryptcurrency, it might be easy to forget about crypto taxation. Almost every bitcoin or other "altcoin" transaction — mining, spending, trading, exchanging, air drops, etc. — will likely be a taxable event for U.S. tax purposes.
Without a doubt, 2018 will be a landmark year for Internal Revenue Service enforcement of cryptocurrency gains. Taxpayers should stay ahead of the game rather than be reactionary. The IRS is always more lenient with taxpayers who come forward on their own accord rather than those that get discovered. Coming forward now actually could be the difference between criminal penalties and simply paying.
source