The article aims to cover the issue of foreign entities having a “fixed establishment” in a given country. A phenomenon discussed at length in recent months, but one that entities conducting digital business seem to have not really explored in great detail in the context of determination of the principles of taxation of VAT transactions. In this article, we will attempt to analyse the definition of FE on the basis of both binding legal regulations and the existing Polish and EU judicial decisions. At the same time, we will try to answer the question about the impact of the practice of tax authorities pursued in the area of interpretation of the conditions for a FE to be established on the stability of tax settlements of taxpayers operating in the digital industry. In addition to that, the authors will also try to arrive at a balance among the current views on FE, which depict Poland from the tax administration perspective as a country with highly unstable tax practices, detached from logical arguments and unaware of the nature of business.