Income tax the discussion of taxation by the United States of foreign persons. Residents, however, are generally subject to income tax on all worldwide income. A very few countries (notably Singapore and Hong Kong) tax residents only on income earned in or remitted to the country. Residence is often defined for individuals as presence in the country for more than 183 days. Most countries base residence of entities on either place of organization or place of management and control. The United Kingdom has three levels of residence. Most systems define income subject to tax broadly for residents, but tax nonresidents only on
Income tax in the United States of certain types of business expenses. Individuals are also allowed credits related to education expenses, retirement savings, child care expenses, some health care premiums, and a credit for each child. Each of the credits is subject to specific rules and limitations. Some credits are treated as refundable payments. Alternative Minimum Tax: All taxpayers are also subject to the Alternative Minimum Tax if their income exceeds certain exclusion amounts. This tax applies only if it exceeds regular income tax, and is reduced by some credits. Additional Medicare Tax: High-income earners may also have to pay an additional 0.9% tax on wages,