If you have self-employment income (Category B) in Portugal, your tax is calculated under one of two regimes: simplified or organized accounting. This article explains the difference and why FIZ may show an estimate warning for organized accounting users.
Simplified regime (Regime Simplificado)
This is the default regime for most self-employed workers. Instead of deducting actual expenses, the tax authority applies fixed coefficients to your gross income to determine taxable income.
Common coefficients under Art. 31 CIRS:
Income type | Coefficient | Taxable portion |
Sales of goods (commerce) | 0.15 | 15% of income |
Professional services | 0.75 | 75% of income |
Intellectual property | 0.95 | 95% of income |
Rental income — short-term AL (outside pressure zones) | 0.35 | 35% of income |
Rental income — short-term AL (in pressure zones) | 0.50 | 50% of income |
Agricultural subsidies (farming activity) | 0.10 | 10% of income |
Agricultural subsidies (non-farming) | 0.30 | 30% of income |
Example: If you earn 50,000€ from professional services, your taxable income is 50,000€ × 0.75 = 37,500€. The remaining 25% is assumed to cover your business expenses — you don't need to prove them.
Who benefits: Freelancers and consultants with relatively low business expenses (less than 25% of income for services).
Organized accounting (Contabilidade Organizada)
Under organized accounting, you deduct actual, documented expenses from your gross income. This requires:
A registered accountant (contabilista certificado)
Proper bookkeeping with invoices and receipts
Submission of additional tax annexes (e.g., IES)
Who benefits: Businesses with significant expenses (office rent, employees, equipment, supplies) where actual deductions exceed the simplified regime coefficients.
Mandatory threshold: If your annual gross income exceeds 200,000€, organized accounting is mandatory.
Why FIZ shows an estimate for organized accounting
FIZ's wizard collects your income data but does not have access to your full expense records (which your accountant manages). For organized accounting users, FIZ cannot calculate exact taxable income because it doesn't know your actual deductible expenses.
Instead, FIZ uses the simplified regime coefficients as a rough estimate. This means:
The estimated tax shown may be higher or lower than your actual tax liability
The estimate is useful for a ballpark figure, but should not be relied upon for financial planning
Your accountant will calculate the precise amount when preparing your actual filing
How to choose between regimes
Factor | Simplified | Organized |
Expenses > 25% of services income | Consider organized | Better fit |
Expenses < 25% of services income | Better fit | Overpaying for accounting |
Income > 200,000€/year | Not available | Mandatory |
Want simplicity, no accountant | Better fit | Requires accountant |
Have employees or complex operations | Not ideal | Better fit |
Can I switch regimes?
Yes. You can switch from simplified to organized (or vice versa) by submitting a declaration of change to Finanças, typically by the end of March of the year in which you want the change to take effect.
Related articles: - How to Categorize Expenses in e-Fatura
Legal references: - Art. 28 CIRS (regime options for Category B) - Art. 31 CIRS (simplified regime coefficients)