Income tax in the United States These treaties reduce the chance of double taxation by allowing each country to fully tax its citizens and residents and reducing the amount the other country can tax them. Generally the treaties provide for reduced rates of tax on investment income and limits as to which business income can be taxed. The treaties each define which taxpayers can benefit from the treaty. The United States social insurance system is funded by a tax similar to an income tax. Social Security tax of 6.2% is imposed on wages paid to employees. The tax is imposed on both the employer and the
Working Tax Credit significant levels of overpayments. In order to reduce the overpayment problem, the income disregard was raised tenfold from £2,500 to £25,000 with effect from 2006/07. Income for tax credit purposes is "in principle" assessed similarly to UK income tax. Thus 'income' (c/f 'taxable income') consists of what the individual receives from gross earned and unearned sources—less allowances for 'expenditures' that would reduce that income. But, unlike income tax, tax credits measure income based on family 'household', rather than the individuals within. Also the effect of "income disregard" —to mask large annual increases in resources from reassessment— weakens comparisons with a