<p>The evaluation of taxpayers' compliance costs has grown in significance within tax system research over the last 15 years. In 2001, two surveys of VAT and personal income taxpayers were conducted in Slovenia to evaluate compliance costs for the 2000 fiscal year. This paper presents the results of research into compliance costs for personal income tax in Slovenia. The results show that compliance costs for personal income tax are relatively low, primarily because most taxpayers consider filing their tax declaration to be a simple procedure, which means that consultancy costs are low.</p>