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Around the world

Income taxes are used in most countries around the world. The tax systems vary greatly and can consist of a flat fixed rate, progressive, or regressive, structures depending on the type of tax. Comparison of tax rates around the world is a difficult and somewhat subjective enterprise. Tax laws in most countries are extremely complex, and tax burden falls differently on different groups in each country and sub-national unit. Of course, services provided by governments in return for taxation also vary, making comparisons all the more difficult.

Countries that tax income generally use one of two systems: territorial or residential. In the territorial system, only local income – income from a source inside the country – is taxed. In the residential system, residents of the country are taxed on their worldwide (local and foreign) income, while non-residents are taxed only on their local income. In addition, a very small number of countries, notably the United States, also tax their non-resident citizens on worldwide income.

Countries with a residential system of taxation usually allow deductions or credits for the tax that residents already pay to other countries on their foreign income. Many countries also sign tax treaties with each other to eliminate or reduce double taxation.

Countries do not necessarily use the same system of taxation for individuals and corporations. For example, France uses a residential system for individuals but a territorial system for corporations, while Singapore does the opposite, and Brunei taxes corporate but not personal income.