Decomposing the revenue implications of the global minimum tax

Abstract We develop a methodology to decompose the tax revenue impact of the global minimum tax introduced in 2024 into several components and quantify its potential impact on profit shifting. We apply the methodology to a dataset comprising 34 thousand country-multinational observations combined from corporate tax returns, financial statements, and global country-by-country reports of all multinationals active in Slovakia in 2020. We find that the global minimum tax has the potential to decrease profit shifting by most multinationals, which are on average likely to pay higher effective tax rates in most countries worldwide post-reform. We find that Slovak corporate tax revenues will increase by 4%, with half of the increase due to its minimum top-up taxes. The other half of the increase is corporate income tax on profits that will no longer be shifted out of the country. We expect the global minimum tax to target 49% of previously shifted profits.