Flat Tax
A tax system that applies a single uniform rate to all taxable income, without progressive brackets and often with limited deductions.
Definition
What it is
A flat tax applies a single statutory rate to all taxable income above a basic allowance. It contrasts with progressive systems, where the marginal rate rises with income. Flat-tax systems can apply to corporate income, personal income, or both. Estonia (20%, but applied to distributed profits only), Romania (10% personal, 16% corporate), Bulgaria (10%), Hungary (15% personal), and Russia historically (13%) are well-known examples.
Variants
- **Pure flat tax**: one rate, broad base, limited deductions
- **Distributed-profits flat tax**: Estonia's model - corporate tax is paid only when profits are distributed, encouraging reinvestment
- **Flat regimes for non-domiciled or new residents**: Italy's EUR 100,000-200,000 lump sum, Greece's alternative regime, Switzerland's cantonal lump-sum tax
Trade-offs
Proponents argue flat taxes simplify compliance, reduce distortions, and attract capital and talent. Critics highlight reduced progressivity and revenue concerns. From a founder's perspective, jurisdictions with attractive flat-tax regimes (Estonia for retained earnings, Italy and Greece for high-net-worth relocation) are popular structuring tools, particularly when combined with strong treaty networks and EU access.
When you'll encounter it
You will hear about flat taxes when comparing personal-residency options for founders relocating across the EU, when considering Estonia for an operating or holding entity (especially during high-growth retained-earnings phases), or when evaluating low-rate jurisdictions like Bulgaria or Romania for a back-office or shared-service company.
Used in our guides
FAQ
Is Estonia really a 0% tax country?
No. Estonia applies a 20% corporate tax, but only on distributed profits. Retained and reinvested profits are not taxed at the corporate level until distribution.
Are flat-tax regimes always low-tax?
Not always. They are flat, not necessarily low. Some flat regimes apply moderate rates (15%-20%) but avoid steep marginal brackets.
Do flat taxes interact with Pillar Two?
Yes. A 9% or 10% corporate flat tax may fall below the 15% GloBE minimum, triggering top-up tax for in-scope MNE groups.
References
- Tax Foundation - Flat Tax Overview https://taxfoundation.org/
- Estonian Tax and Customs Board - Corporate Income Tax https://www.emta.ee/en/business-client/taxes-and-payment/income-taxes/corporate-income-tax