According the legislation of my country there is no tax for bitcoin transactions. Even more there is no VAT because bitcoin is considered not a coin, like as fiat, but an agreement between two parties
In any bitcoin doesn't have tax for transactions. But if you wish you could consider minig fees as the tax for your every transaction. Apart from this fees there is no any charges for bitcoin.
Those transaction fees are considered as a tax on my part but not connected into government but its just a little amount to consider as a tax. Its impossible for government to impose taxes on bitcoin and thats the good thing about it. Unlike fiat which is already regulated by government then tax is expected.