Individuals who stay in the United States for 183 days or more during a tax year are considered to have moved there and to be tax residents.

The same applies to individuals who stay in the United States for 31 days or more during a tax year, if this results in a total of 183 days or more when combining the days spent in that year and the two preceding years. When calculating the number of days, 1/6 of the days of presence in the year of arrival, 1/3 of the days in year two, and all days in year three are counted.

Tax residency can also be established on the basis of “green card” status. This means that individuals who have lawful permanent residence in the United States are considered tax residents.

Resident taxpayers and U.S. citizens are taxed on their worldwide income in the United States.

USA has a progressive tax system, with rates ranging from 10 to 37%.

USA grants tax credit for taxes paid abroad, limited to the amount of U.S. tax payable on the same income.

USA does not levy wealth tax.

The tax year in USA generally corresponds with the calendar year.

The individual tax return in USA must generally be filed by the 15th day of the fourth month of the year following the tax year.

The name of the tax authority in USA is Internal Revenue Service (IRS).

USA has tax treaties with approximately 70 countries, including Norway.

USA has property tax in certain states, with rates varying from state to state.