Income tax in the United States dates. Some states permit related corporations to file combined or consolidated returns. Most states and localities imposing income tax require estimated payments where tax exceeds certain thresholds, and require withholding tax on payment of wages. Puerto Rico is treated as a separate taxing entity from the USA; its income tax rates are set independently, and only some residents there pay federal income taxes (though everyone must pay all other federal taxes). The unincorporated territories Guam, American Samoa, and the Virgin Islands also impose income tax separately, under a "mirror" tax law based on federal income tax law. Proposals have been
Working Tax Credit from the earlier benefit for working families known as Family Credit (FC), which had been in operation since 1986. The WFTC shared its assessment of means and period of renewal (6 months) with FC but moved towards a tax credit approach styled on schemes in other countries, which used an annual declaration of income to assess entitlement for a whole year. Tax credits also replaced the child elements in means tested benefits, the Children's Tax Credit in the tax system, and disabled persons tax credit. In 2014 WTC and CTC combined cost £30 billion per year. The basic operation of