I learned from the “Bitcoin Book for Beginners” by my colleague, Mr. Esaki that with regard to bitcoin, the tax Q&As and comments have already been announced by the National Tax Agency. Although consumption tax does not apply, when individuals trade, as a rule, it becomes miscellaneous income, except when it is recognized as business income, and when a corporation transacts, corporation tax (as income of the corporation) will be imposed.
What I thought was a bit unreasonable is that even if you buy something with bitcoin, taxation would apply. For example, if you purchased 1 BTC for 400,000 yen on April 1 and paid 600,000 yen for home appliances at Yamada Electrics on April 10, and then paid 1 BTC because the rate for 1 BTC at that time was 600,000 yen, you would incur a miscellaneous income of 200,000 yen. However, if you had to record the rate every time you bought an item and then compare it to the rate of bitcoin purchase costs, you would not be able to benefit from money markets, rendering the benefits of cryptocurrency pointless. Additionally, it would be incredibly difficult to make frequent purchases of some items in shops. Even though Japan worked on the virtual currency law ahead of other developed nations, the use of the virtual currency will not spread, and this will be the result of such nonsense.
However, when I asked a tax accountant about this issue, it seems that such handling is the same with foreign currency. For example, if you purchased $400 for ¥400,000 on April 1, then the yen depreciated rapidly, and you bought home appliances for ¥600,000 on April 10 at $400 US, you would still incur a miscellaneous income of 200,000 yen. Thus, the tax accountant says that even if you buy things in dollars, if you convert it to Japanese yen to determine the number of dollars, the income has to be taken into account, so from the tax law point of view, it is not theoretically wrong.
Therefore, in order to change such tax laws, it is necessary for bitcoins to be as prevalent as Japanese yen, so that it would not be necessary to convert them into yen to buy things. I dream of this happening someday.