Imposta Sostitutiva

Imposta sostitutiva is a flat-rate substitute tax that replaces Italy's progressive income tax (IRPEF) for certain categories of financial income. For capital gains on financial instruments, the rate is 26%.

Application to prediction markets

If the Agenzia delle Entrate (Italian Revenue Agency) classifies prediction market contracts as financial instruments, gains would be subject to the 26% imposta sostitutiva. This is more favorable than the progressive IRPEF rates, which can reach 43%.

Regime del risparmio

Italian investors can choose between different tax regimes:

• Regime dichiarativo: You declare gains on your annual return and pay 26%. This is the default for international platform trades.
• Regime amministrato: An Italian intermediary withholds tax at source. Not available for foreign prediction market platforms.

Loss compensation

Capital losses (minusvalenze) can be carried forward for 4 years to offset future gains of the same category. However, the loss offset rules are complex and depend on the type of income.

Comparison with other European flat rates

Italy's 26% imposta sostitutiva sits in the middle of European flat capital gains rates:

• Germany: ~26.4% (Abgeltungsteuer + Soli) — virtually identical
• Portugal: 28% (without englobamento) — slightly higher
• Spain: 19–28% (rentas del ahorro) — progressive but similar range
• Sweden: 30% (inkomst av kapital) — higher
• Ireland: 33% (CGT) — significantly higher

Crypto and prediction market specifics

Italy updated its cryptocurrency tax rules in 2023, introducing a 26% capital gains tax on crypto gains above €2,000. Since Polymarket operates on the Polygon blockchain using USDC, Italian traders may need to consider both the crypto tax framework and the general imposta sostitutiva — potentially with complex interactions between the two.

Frequently asked questions

Do I need an Italian intermediary to use regime amministrato?

Yes. Regime amministrato requires an Italian bank or broker to act as "sostituto d'imposta" (tax substitute), withholding the 26% at source. Since Kalshi and Polymarket are not Italian intermediaries, you must use regime dichiarativo and self-declare.

What's the deadline for filing Modello Redditi?

The Modello Redditi (income tax return) for the previous year is due by November 30. This is later than many European countries, giving Italian traders more time to prepare their documentation.