One of the ways in which entrepreneurs try to gain an unjustified advantage within economic relations is by committing tax fraud. Tax fraud is an integral part of today's economy, and as the ways of committing tax fraud evolve, so do the ways of detecting it. Entire chains of domestic and foreign companies are often involved in tax fraud. In this way, more and more pressure is exerted on the authorities that are supposed to serve to uncover these frauds. The aim of the article is to identify tax fraud as such, as well as the ways in which it is committed, and to analyze how these frauds affect business activities. In cross-border transactions, it is always much more difficult to prove that tax fraud has occurred. Authorities investigating tax fraud at the national level are limited by their national jurisdiction, and international cooperation at the bilateral and European level is therefore very essential in this area. We will probably never get rid of tax fraud completely. However, thanks to consistent cooperation, it is possible to significantly reduce their occurrence.