But there is some uncertainty among tax professionals about whether cryptocurrency investors who buy via foreign exchanges need to go through additional reporting measures.

The IRS has defined cryptocurrencies as property , meaning no matter where you buy your digital coins, you'll pay taxes at your capital gains rate.

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Are certain cryptocurrency exchanges foreign accounts? That's not a philosophical musing. Americans who hold more than a certain amount of money abroad typically have to file reports with both the Internal Revenue Service and the U.S. Treasury. Failure to do so can result in more than $100,000 in fines and time in prison. "U.S. taxpayers may not even be aware of this requirement because it's not something they readily file every year," said Selva Ozelli, a certified public accountant and lawyer who specializes in the digital coins. Here are the rules: Anyone with more than $10,000 abroad usually needs to fill out the Report of Foreign Bank and Financial Accounts, or FBAR, with the Treasury Department each year. Another law — the Foreign Account Tax Compliance Act, or FATCA — requires certain U.S. taxpayers to describe their overseas accounts on Form 8938, when they file their taxes with the IRS.

It's clear the IRS has defined cryptocurrencies as property, and so no matter where you buy your digital coins you need to pay taxes at your capital gains rate on them. But there is some uncertainty among tax professionals about whether cryptocurrency investors who buy off foreign exchanges need to go through these additional foreign account reporting measures. "There probably is an FBAR requirement, but I wouldn't go as far as to say there always is one," said Kevin F. Sweeney, a former federal tax prosecutor and an attorney at Chamberlain Hrdlicka in Philadelphia. He said a lack of guidance from the government has left a "black hole" in his analysis. "It would seem awfully unfair if they would expect taxpayers to know that — and to then issue penalties for taxpayers who didn't do that — when practitioners can't even 100 percent figure out if there's an FBAR requirement," he said.

U.S. taxpayers may not even be aware of this requirement. Selva Ozelli a CPA and lawyer who specializes in the digital coins