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Flat tax

Type of tax

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Related on Lably

Through Tax, Tax rate and Tax deduction

A flat tax system is usually discussed in the context of an income tax, where progressivity is common, but it may also apply to taxes on consumption, property or transfers.

Major categories

Flat tax proposals differ in how the subject of the tax is defined.

True flat-rate income tax

A true flat-rate tax is a system of taxation where one tax rate is applied to all personal income with no deductions.

Marginal flat tax

Where deductions are allowed, a 'flat tax' is a progressive tax with the special characteristic that, above the maximum deduction, the marginal rate on all further income is constant. Such a tax is said to be marginally flat above that point. The difference between a true flat tax and a marginally flat tax can be reconciled by recognizing that the latter simply excludes certain types of income from being defined as taxable income; hence, both kinds of tax are flat on taxable income.

Flat tax with limited deductions

Modified flat taxes have been proposed which would allow deductions for a very few items, while still eliminating the vast majority of existing deductions. Charitable deductions and home mortgage interest are the most discussed examples of deductions that would be retained, as these deductions are popular with voters and are often used. Another common theme is a single, large, fixed deduction. This large fixed deduction would compensate for the elimination of various existing deductions and would simplify taxes, having the side-effect that many (mostly low income) households will not have to file tax returns.

Hall–Rabushka flat tax

Designed by economists at the Hoover Institution, Hall–Rabushka is a flat tax on consumption. Principally, Hall–Rabushka accomplishes a consumption tax effect by taxing income and then excluding investment. Robert Hall and Alvin Rabushka have consulted extensively in designing the flat tax systems in Eastern Europe.

Negative income tax

The negative income tax (NIT), which Milton Friedman proposed in his 1962 book Capitalism and Freedom, is a type of flat tax. The basic idea is the same as a flat tax with personal deductions, except that when deductions exceed income, the taxable income is allowed to become negative rather than being set to zero. The flat tax rate is then applied to the resulting "negative income," resulting in a "negative income tax" that the government would owe to the household—unlike the usual "positive" income tax, which the household owes the government.

For example, let the flat rate be 20%, and let the deductions be $20,000 per adult and $7,000 per dependent. Under such a system, a family of four making $54,000 a year would owe no tax. A family of four making $74,000 a year would owe tax amounting to 0.20 × (74,000 − 54,000) = $4,000, as would be the case under a flat tax system with deductions. Families of four earning less than $54,000 per year, however, would experience a "negative" amount of tax (that is, the family would receive money from the government instead of paying to the government). For example, if the family earned $34,000 a year, it would receive a check for $4,000. The NIT is intended to replace not just the USA's income tax, but also many benefits low income American households receive, such as food stamps and Medicaid. The NIT is designed to avoid the welfare trap—effective high marginal tax rates arising from the rules reducing benefits as market income rises. An objection to the NIT is that it is welfare without a work requirement. Those who would owe negative tax would be receiving a form of welfare without having to make an effort to obtain employment. Another objection is that the NIT subsidizes industries employing low-cost labor, but this objection can also be made against current systems of benefits for the working poor.

Capped flat tax

A capped flat tax is one in which income is taxed at a flat rate until a specified cap amount is reached. For example, the United States Federal Insurance Contributions Act tax is 6.2% of gross compensation up to a limit (in 2025, up to $176,100 of earnings, for a maximum tax of $10,918.20). This cap has the effect of turning a nominally flat tax into a regressive tax.

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