Flat tax proposals differ in how the subject of the tax is defined.
A true flat rate tax is a system of taxation where one tax rate is applied to all personal income with no deductions.
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.
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.
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.
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.
A capped flat tax is one in which income is taxed at a flat rate until a specified cap amount is reached. For example, in 2014, the United States Federal Insurance Contributions Act tax is 6.2% of gross compensation up to a limit of $117,000 of gross compensation (resulting in a maximum Social Security tax of $7,254). This cap has the effect of turning a nominally flat tax into a regressive tax.
In devising a flat tax system, several recurring issues must be enumerated, principally with deductions and the identification of when money is earned.
Since a central tenet of the flat tax is to minimize the compartmentalization of incomes into myriad special or sheltered cases, a vexing problem is deciding when income occurs. This is demonstrated by the taxation of interest income and stock dividends. The shareholders own the company and so the company's profits belong to them. If a company is taxed on its profits, then the funds paid out as dividends have already been taxed. It's a debatable question if they should subsequently be treated as income to the shareholders and thus subject to further tax. A similar issue arises in deciding if interest paid on loans should be deductible from the taxable income since that interest is in-turn taxed as income to the loan provider. There is no universally agreed answer to what is fair. For example, in the United States, dividends are not deductible but mortgage interest is deductible. Thus a Flat Tax proposal is not fully defined until it differentiates new untaxed income from a pass-through of already taxed income.
Taxes, in addition to providing revenue, can be potent instruments of policy. For example, it is common for governments to encourage social policy such as home insulation or low income housing with tax credits rather than constituting a ministry to implement these policies. In a flat tax system with limited deductions such policy administration, mechanisms are curtailed. In addition to social policy, flat taxes can remove tools for adjusting economic policy as well. For example, in the United States, short-term capital gains are taxed at a higher rate than long-term gains as means to promote long-term investment horizons and damp speculative fluctuation. Thus, if one assumes that government should be active in policy decisions such as this, then claims that flat taxes are cheaper/simpler to administer than others are incomplete until they factor in costs for alternative policy administration.
In general, the question of how to eliminate deductions is fundamental to the flat tax design: deductions dramatically affect the effective "flatness" in the tax rate. Perhaps the single biggest necessary deduction is for business expenses. If businesses were not allowed to deduct expenses, businesses with a profit margin below the flat tax rate could never earn any money since the tax on revenues would always exceed the earnings. For example, grocery stores typically earn pennies on every dollar of revenue; they could not pay a tax rate of 25% on revenues unless their markup exceeded 25%. Thus, corporations must be able to deduct operating expenses even if individual citizens cannot. A practical difficulty now arises as to identifying what is an expense for a business. For example, if a peanut butter maker purchases a jar manufacturer, is that an expense (since they have to purchase jars somehow) or a sheltering of their income through investment? Flat tax systems can differ greatly in how they accommodate such gray areas. For example, the "9-9-9" flat tax proposal would allow businesses to deduct purchases but not labor costs. (This effectively taxes labor-intensive industrial revenue at a higher rate.) How deductions are implemented will dramatically change the effective total tax, and thus the flatness of the tax. Thus, a flat tax proposal is not fully defined unless the proposal includes a differentiation between deductible and non-deductible expenses.
Flat tax benefits higher income brackets progressively due to decline in marginal value. For example, if a flat tax system has a large per-citizen deductible (such as the "Armey" scheme below), then it is a progressive tax. As a result, sometimes the term Flat Tax is actually a shorthand for the more proper marginally flat tax.
One type of flat tax would be imposed on all income once—at the source of the income. Hall and Rabushka (1995) includes a proposed amendment to the U.S. Internal Revenue Code that would implement the variant of the flat tax they advocate. This amendment, only a few pages long, would replace hundreds of pages of statutory language (although most statutory language in taxation statutes is not directed at specifying graduated tax rates). As it now stands, the U.S. Internal Revenue Code is over several million words long, and contains many loopholes, deductions, and exemptions which, advocates of flat taxes claim, render the collection of taxes and the enforcement of tax law complicated and inefficient. It is further argued that current tax law retards economic growth by distorting economic incentives, and by allowing, even encouraging, tax avoidance. With a flat tax, there are fewer incentives than in the current system to create tax shelters, and to engage in other forms of tax avoidance. Flat tax critics contend that a flat tax system could be created with many loopholes, or a progressive tax system without loopholes, and that a progressive tax system could be as simple, or simpler, than a flat tax system. A simple progressive tax would also discourage tax avoidance.
Under a pure flat tax without deductions, every tax period a company would make a single payment to the government covering the taxes on the employees and the taxes on the company profit. For example, suppose that in a given year, a company called ACME earns a profit of 3 million, spends 2 million in wages, and spends 1 million on other expenses that under the tax law is taxable income to recipients, such as the receipt of stock options, bonuses, and certain executive privileges. Given a flat rate of 15%, ACME would then owe the U.S. Internal Revenue Service (IRS) (3M + 2M + 1M) × 0.15 = 900,000. This payment would, in one fell swoop, settle the tax liabilities of ACME's employees as well as the corporate taxes owed by ACME. Most employees throughout the economy would never need to interact with the IRS, as all tax owed on wages, interest, dividends, royalties, etc. would be withheld at the source. The main exceptions would be employees with incomes from personal ventures. The Economist claims that such a system would reduce the number of entities required to file returns from about 130 million individuals, households, and businesses, as at present, to a mere 8 million businesses and self-employed.
This simplicity depends, however, on the absence of deductions of any kind being allowed (or at least no variability in the deductions of different people). Furthermore, if income of differing types are segregated (e.g., pass-thru, long term cap gains, regular income, etc.) then complications ensue. For example, if realized capital gains were subject to the flat tax, the law would require brokers and mutual funds to calculate the realized capital gain on all sales and redemption. If there were a gain, a tax equal to 15% of the amount of the gain would be withheld and sent to the IRS. If there were a loss, the amount would be reported to the IRS. The loss would offset gains, and the IRS would settle up with taxpayers at the end of the period. Lacking deductions, this scheme cannot be used to implement economic and social policy indirectly by tax credits and thus, as noted above, the simplifications to the government's revenue collection apparatus might be offset by new government ministries required to administer those policies.
The Russian Federation is considered a prime case of the success of a flat tax; the real revenues from its Personal Income Tax rose by 25.2% in the first year after the Federation introduced a flat tax, followed by a 24.6% increase in the second year, and a 15.2% increase in the third year. The Laffer curve predicts such an outcome, attributing the primary reason for the greater revenue to higher levels of economic growth stemming from the introduction of the flat tax.
The Russian example is often used as proof of the validity of this analysis, despite an International Monetary Fund study in 2006 which found that there was no sign "of Laffer-type behavioral responses generating revenue increases from the tax cut elements of these reforms" in Russia or in other countries.
Taxes other than the income tax (for example, taxes on sales and payrolls) tend to be regressive. Hence, making the income tax flat could result in a regressive overall tax structure. Under such a structure, those with lower incomes tend to pay a higher proportion of their income in total taxes than the affluent do. The fraction of household income that is a return to capital (dividends, interest, royalties, profits of unincorporated businesses) is positively correlated with total household income. Hence a flat tax limited to wages would seem to leave the wealthy better off. Modifying the tax base can change the effects. A flat tax could be targeted at income (rather than wages), which could place the tax burden equally on all earners, including those who earn income primarily from returns on investment. Tax systems could utilize a flat sales tax to target all consumption, which can be modified with rebates or exemptions to remove regressive effects (such as the proposed FairTax in the U.S.).
A flat tax system and income taxes overall are not inherently border-adjustable; meaning the tax component embedded into products via taxes imposed on companies (including corporate taxes and payroll taxes) are not removed when exported to a foreign country (see Effect of taxes and subsidies on price). Taxation systems such as a sales tax or value added tax can remove the tax component when goods are exported and apply the tax component on imports. The domestic products could be at a disadvantage to foreign products (at home and abroad) that are border-adjustable, which would impact the global competitiveness of a country. However, it's possible that a flat tax system could be combined with tariffs and credits to act as border adjustments (the proposed Border Tax Equity Act in the U.S. attempts this). Implementing an income tax with a border adjustment tax credit is a violation of the World Trade Organization agreement. Tax exemptions (allowances) on low income wages, a component of most income tax systems could mitigate this issue for high labour content industries like textiles that compete Globally.
In a subsequent section, various proposals for flat tax-like schemes are discussed, these differ mainly on how they approach with the following issues of deductions, defining income, and policy implementation.
Flat tax proposals have made something of a "comeback" in recent years. In the United States, former House Majority Leader Dick Armey and FreedomWorks have sought support for the flat tax (Taxpayer Choice Act). In other countries, flat tax systems have also been proposed, largely as a result of flat tax systems being introduced in several countries of the former Eastern Bloc, where it is generally thought to have been successful, although this assessment has been disputed (see below).
The countries that have recently reintroduced flat taxes have done so largely in the hope of boosting economic growth. The Baltic countries of Estonia, Latvia and Lithuania have had flat taxes of 24%, 25% and 33% respectively with a tax exempt amount, since the mid-1990s. On 1 January 2001, a 13% flat tax on personal income took effect in Russia. Ukraine followed Russia with a 13% flat tax in 2003, which later increased to 15% in 2007. Slovakia introduced a 19% flat tax on most taxes (that is, on corporate and personal income, for VAT, etc., almost without exceptions) in 2004. Romania introduced a 16% flat tax on personal income and corporate profit on 1 January 2005. Macedonia introduced a 12% flat tax on personal income and corporate profit on 1 January 2007 and promised to cut it to 10% in 2008. Albania has implemented a 10% flat tax from 2008. Bulgaria applies flat tax rate of 10% for corporate profits and personal income tax since 2008.
In the United States, while the Federal income tax is progressive, eight states — Colorado, Illinois, Indiana, Massachusetts, Michigan, ((North Carolina)) Pennsylvania, and Utah — tax household incomes at a single rate, ranging from 3.07% (Pennsylvania) to 5.8% (North Carolina). Pennsylvania even has a pure flat tax with no zero-bracket amount.
Paul Kirchhof, who was suggested as the next finance minister of Germany in 2005, proposed introducing a flat tax rate of 25% in Germany as early as 2001, which sparked widespread controversy. Some claim the German tax system is the most complex one in the world.
On 27 September 2005, the Dutch Council of Economic Advisors recommended a flat rate of 40% for income tax in the Netherlands. Some deductions would be allowed, and persons over 65 years of age would be taxed at a lower rate.
In the United States, proposals for a flat tax at the federal level have emerged repeatedly in recent decades during various political debates. Jerry Brown, former and current Democratic Governor of California, made the adoption of a flat tax part of his platform when running for President of the United States in 1992. At the time, rival Democratic candidate Tom Harkin ridiculed the proposal as having originated with the "Flat Earth Society". Four years later, Republican candidate Steve Forbes proposed a similar idea as part of his core platform. Although neither captured his party's nomination, their proposals prompted widespread debate about the current U.S. income tax system.
Flat tax plans that are presently being advanced in the United States also seek to redefine "sources of income"; current progressive taxes count interest, dividends and capital gains as income, for example, while Steve Forbes's variant of the flat tax would apply to wages only.
In 2005, Senator Sam Brownback, a Republican from Kansas, stated he had a plan to implement a flat tax in Washington, D.C.. This version is one flat rate of 15% on all earned income. Unearned income (in particular capital gains) would be exempt. His plan also calls for an exemption of $30,000 per family and $25,000 for singles. Mississippi Republican Senator Trent Lott stated he supports it and would add a $5,000 credit for first time home buyers and exemptions for out of town businesses. DC Delegate Eleanor Holmes Norton's position seems unclear, however DC mayor Anthony Williams has stated he is "open" to the idea.
Flat taxes have also been considered in the United Kingdom by the Conservative Party. In September 2005, George Osborne, then in opposition, said that while he was "fully conscious that we may not be able to introduce a pure flat tax, we may be able to move towards simpler and flatter taxes." However, it was roundly rejected by Gordon Brown, then the Labour Chancellor of the Exchequer, who said that it was "An idea that they say is sweeping the world, well sweeping Estonia, well a wing of the neo-conservatives in Estonia", and criticised it thus: "The millionaire to pay exactly the same tax rate as the young nurse, the home help, the worker on the minimum wage".
These are countries, as well as minor jurisdictions with the autonomous power to tax, that have adopted tax systems that are commonly described in the media and the professional economics literature as a flat tax. In some countries different rates apply to different kinds of income, the main rate for personal income is shown below.
At the federal level, the United States taxes personal income at progressive rates. Most states also tax income, most of them also at progressive rates, but some use a flat tax rate. Hong Kong: Some sources claim that Hong Kong has a flat tax, though its salary tax structure has several different rates ranging from 2% to 17% after deductions. Taxes are capped at 15% of gross income, so this rate is applied to upper income returns if taxes would exceed 15% of gross otherwise. Accordingly, Duncan B. Black of Media Matters for America, says "Hong Kong's 'flat tax' is better described as an 'alternative maximum tax.'" Alan Reynolds of the Cato Institute similarly notes that Hong Kong's "tax on salaries is not flat but steeply progressive." Hong Kong has, nevertheless, a flat profit tax regime.
Albania introduced a flat tax of 10% on personal income in 2008, and replaced it with two rates of 13% and 23% in 2014.
Czech Republic introduced a flat tax of 15% on personal income in 2008, and a second higher rate of 22% in 2013.
Iceland introduced a flat tax on personal income in 2007, at a national rate of 22.75%. With the additional municipal rate, the total tax rate was up to 36%. In 2010, Iceland replaced its flat tax system with progressive national rates of 24.1 to 33%, for a combined (national and municipal) top rate of 46.28%.
Montenegro introduced a flat tax of 15% on personal income in 2007, reduced to 12% in 2009 and 9% in 2010. It introduced a second higher rate of 15% on salaries in 2013, reduced to 13% in 2015 and 11% in 2016.
Saint Helena introduced a flat tax of 25% on personal income in 2012, and replaced it with two rates of 26% and 31% in 2015.
Slovakia introduced a flat tax of 19% on personal income in 2004, and a second higher rate of 25% in 2013.
Ukraine introduced a flat tax of 13% on personal income in 2004, increased to 15% in 2007, and introduced a second higher rate of 17% in 2011. The second rate was increased to 20% in 2015, and the first rate was increased to 18% in 2016.
These are countries where concrete flat tax proposals are being considered by influential politicians or political parties. Australia: In 2010, the former leader of the Liberal Party and former Prime Minister Tony Abbott, expressed his desire for a tax debate that included the implementation of a flat tax system. However, the then Australian Labor Party government believed that a flat tax would be detrimental to middle income earners, who would see a rise in taxation from their current levels.
Faroe Islands: The cabinet appointed in November 2011, consisting of the Union Party, People's Party, Self-Government Party and Centre Party, defined a flat tax system as a part of its financial policy. The bill introducing the flat tax passed on 23 December 2011.
Panama: During the 2008–2009 political campaign, presidential candidate Ricardo Martinelli included in his government plan the replacement of the current tax system implemented by president Martin Torrijos with a 10 or 15% flat tax rate in order to raise employment and wages.
Poland: In the 2007 elections, the Civic Platform gained 41.5% of the votes, running on a 15% flat tax as one of the main points in the party program.
Advocates of the flat tax argue that the former communist states of Eastern Europe have benefited from the adoption of a flat tax. Some of these nations have experienced strong economic growth of 6% and higher in recent years, particularly the Baltic countries, who experience exceptional GDP growth of around 10% yearly. Some argue that other factors, primarily the advent of capitalist economic systems and rapid market expansion after Soviet (communist) domination explain the rapid growth. Some argue that economic growth in these countries would likely have occurred regardless of the chosen tax system.Lithuania, which levies a flat tax rate of 15% (previously 20%) on its citizens, has experienced -15.8%, +1.3%, and +5.8% change in GDP from 2009-2011. The growth in 2011 is listed as being high compared to other nations in the region and 46th globally. The unemployment rate of 15.4% is listed as higher than 151 other nations and the inflation rate of 4.1% is greater than 103 other currencies including that of the European Union
In Estonia, which has had a flat tax since 1994 (rate has been 20% since 2015, and used to be 21-26%), studies have shown that the significant increase in tax revenue experienced was caused partly by a disproportionately rising VAT revenue. Moreover, Estonia and Slovakia have high social contributions, pegged to wage levels. Both matters raise questions regarding the justice of the flat tax system, and thus its long-term political sustainability. The Estonian economist and former chairman of his country's parliamentary budget committee Olev Raju, stated in September 2005 that "income disparities are rising and calls for a progressive system of taxation are getting louder – this could put an end to the flat tax after the next election". However, this did not happen, since after the 2007 elections a right-wing coalition was formed which has stated its will to keep the flat tax in existence. However, critics argue that the tax rates these countries have are actually more progressive than flat.
Hungary introduced a flat tax at 16% on 1 January 2011.
According to a 2010 study published in the Brussels newspaper L'Anglophone, the tax burden for typical workers in Central and Eastern Europe's "flat tax" countries is slightly higher (40.3% versus 40.2% of the total cost of employment) than that of the progressive systems elsewhere in the EU. "Slovakia has a “flat tax” rate of 19%," wrote the authors, "but its employers pay a 35.2% contribution to social security (higher than the 34.8% in Belgium) and, in addition to the flat income tax, employees have 13.4% deducted for social security (also higher than the 13.07% in Belgium)," adding that a typical Slovak worker's Tax Freedom Day is a day later than a Finnish worker's. Slovakia reintroduced progressive tax rates in 2013.