Abstract: Nowadays, more and more Romanians do their shopping online, accessing various websites where individual persons/legal entities display the products they want to sell. Thus, it can be seen that the field of electronic commerce is gaining more and more ground, to the detriment of the traditional one. In this article we aim to present the accounting and tax treatment of online trading activities carried out by authorized natural persons and how to proceed when deciding to switch from single-entry bookkeeping to double-entry bookkeeping.