This article analyses the concept of a service PE, as defined in article 5(4) of the PL-NO Tax Treaty, which has no equivalent in any other tax treaty signed by Poland or Norway and differs from the service PE provision in the Commentary on the OECD Model (2008) and the UN Model (2011). As a result, there is no guidance of the tax authorities or case law in this regard. This article addresses this legal gap in detail.