Income tax in the United States increase complexity, irrespective of the system's flatness or lack thereof. Income tax is also levied by most U.S. states and many localities on individuals, corporations, estates, and trusts. These taxes are in addition to federal income tax and are deductible for federal tax purposes. State and local income tax rates vary from 1% to 16% of taxable income. Some state and local income tax rates are flat (single rate) and some are graduated. State and local definitions of what income is taxable vary highly. Some states incorporate the federal definitions by reference. Taxable income is defined separately and differently for
Working income tax benefit 453 of the income tax return if their income exceeds $3,000 for the calendar year. However, the additional paperwork required to claim the credit is complex, involving a the 42-step process on Schedule 6 of Canada's main income-tax form. As of 2016, the WITB is worth up to $1,028 for a single individual and $1,868 for couples and single-parent families. Benefits increase and then decrease with income. At an income of $18,529 for single individuals or $28,576 for families the benefits decrease to $0. WITB is estimated to benefit 1.4 million working Canadians annually, at a cost to the federal