Flat Tax

Tax Planning
Updated Apr 2026

A tax system that applies a single uniform rate to all taxpayers regardless of income level.

Tax laws change annually and vary by country. The information on this page is for educational purposes only. Always verify figures with current official sources (IRS, HMRC, CRA, ATO) and consult a qualified tax professional before making any tax-related decision.

What is Flat Tax?

A flat tax applies the same percentage rate to all taxpayers regardless of their income level, in contrast to a progressive system where rates rise with income. Proponents argue it simplifies tax compliance, eliminates bracket-creep distortions, and reduces disincentives to earn more. Critics contend it is regressive in practice because a fixed rate consumes a larger share of disposable income for lower earners. Several countries, including Russia (until 2021) and Estonia, have used flat income tax systems, and some U.S. states apply a flat rate to state income.

Example

Example

Under a hypothetical 15% flat tax, a person earning $40,000 pays $6,000 (15%), and a person earning $400,000 also pays 15%—or $60,000. Both pay the same rate, but the lower earner retains $34,000 net while the higher earner retains $340,000, illustrating why critics view flat taxes as regressive relative to disposable income.

Source: Tax Foundation — Flat Tax

Sources
  1. Tax Foundation — Flat Tax
  2. Investopedia — Flat Tax