In today's global business world, startups play a key role in driving innovation, job creation and economic growth. However, one of the key factors affecting the success and competitiveness of startups is the tax burden in different jurisdictions. Accordingly, this chapter analyzes various aspects of taxation of startup companies in three different regions: the Republic of Croatia, the countries of the European Union and the United States of America. The analysis of the comparison of the tax burden of startup companies in the Republic of Croatia with selected countries of the European Union and the United States highlights the crucial importance of understanding the differences in tax systems when assessing the attractiveness of the market for startup business. In Croatia, startups are subject to general tax regulations, with VAT of 25% on certain revenues and corporate tax of 18%. The analysis highlights the need for a careful review of all tax liabilities, including VAT, corporate tax and other charges. Within the European Union, different countries offer different incentives for startup companies, including different corporate tax rates and incentives for investment in research, development and innovation. In the United States, the tax regime for startups is complex and varied, depending on the structure of the company, income taxes, corporate tax, and additional taxes such as social security and capital gains. Tax credits play a key role in supporting startup businesses and reducing the tax burden. The analysis concludes that different jurisdictions offer different approaches to the taxation of startups and highlights the importance of careful consideration of tax factors when choosing a market for startup business