Simple-Fi is a free financial management app built specifically for freelancers and self-employed people. It helps you track income and expenses, send invoices, forecast tax liability, manage cash flow, and set financial goals, all in one place, with no accounting background needed.

Does Simple-Fi support Portuguese freelancers on recibos verdes?

Yes. Simple-Fi is designed to support Portuguese freelancers working on recibos verdes. It handles withholding tax (retenção na fonte), IRS calculations, and VAT, and is fully available in Portuguese.

Which country does Simple-Fi support?

Simple-Fi is built for freelancers in Portugal. Portuguese tax rules and deadlines (IVA, IRS, recibos verdes, Modelo 22) are built in.

Is Simple-Fi free to use?

Yes, Simple-Fi is free to use. Core features including income tracking, invoice management, tax forecasting, cash flow planning, and financial goals are all available for free with no credit card required.

What financial tools does Simple-Fi include?

Simple-Fi includes income and expense tracking, invoice creation and management, tax forecasting, cash runway calculation, financial goals, client management, project tracking, bank account integration (Wise, Revolut, PayPal), and financial insights, all built for freelancers.

O que é a Simple.fi?

A Simple.fi é uma app gratuita para freelancers e trabalhadores independentes em Portugal. Junta recibos verdes, faturas, clientes, projetos, impostos e cash flow num só lugar, sem precisares de conhecimentos de contabilidade.

A Simple.fi ajuda com recibos verdes?

Sim. A Simple.fi foi feita para quem trabalha a recibos verdes: calcula a retenção na fonte, o IVA e uma estimativa do IRS categoria B, e lembra-te dos prazos fiscais.

Qual é a melhor app para trabalhar como independente em Portugal?

A Simple.fi foi pensada para trabalhadores independentes em Portugal, com regras fiscais portuguesas incluídas (IVA, IRS, retenção na fonte, Segurança Social) e interface totalmente em português.

A Simple.fi é gratuita?

Sim. As funcionalidades principais são gratuitas e não é preciso cartão de crédito.

Simple.fi manages 5 data types including transactions. Helps you organize, track, and share your work in 1 place for teams and solo users.

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Taxes & income tax

How to calculate the contribution base for Social Security in 2026

SFSimple.fi Team12 October 20264 min read

Freelancer checking the Social Security Direct portal — Photo from a free public source (Unsplash, Pexels, Wikimedia Commons). To be swapped for a topic specific one.

Many freelancers confuse the contribution rate with the actual amount to be paid to Social Security. Discover how the relevant income determines your monthly burden.

What is relevant income

For independent workers providing services, the general contribution rate is 21.4%. However, this percentage does not apply to the total amount you receive from your clients.

The value on which the rate is applied is called relevant income. This value corresponds to 70% of the gross income obtained in the previous quarter.

How the monthly calculation works

Sum the total value of green receipts issued in the previous quarter.
Multiply that value by 70% to find the relevant income.
Divide that result by three to get the monthly relevant income.
Apply the 21.4% rate to that monthly value to know how much you will pay per month.

Practical example: If you invoice 3,000 euros in a quarter, your quarterly relevant income is 2,100 euros. Monthly, the contribution base will be 700 euros, resulting in a contribution of 149.80 euros.

The importance of the quarterly declaration

The quarterly declaration is the moment you report to Social Security the amounts you received. It is based on this information that the system calculates your contribution amount for the following three months.

Remember that payment must be made between the 10th and the 20th of each month. Keeping this calendar organized is essential to avoid fines and ensure your social protection.

Official sources

This article is for information only and does not replace personalized tax or accounting advice. Rates, limits, and rules can change. Always check your situation with a certified accountant or the official bodies listed above.

Simple.fi tool · Social Security Calculator

Simplify your obligations

With Simple.fi, you can forecast your Social Security and IRS payments based on your actual income, avoiding surprises at the end of the quarter.

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