Expenses in the simplified regime: the 15% rule

Who this is for

This guide is for people who issue recibos verdes under the simplified regime and provide services. The rule applies to income with a coefficient of 0.75 (activities in the article 151 table) and 0.35 (other services), subparagraphs (b) and (c) of CIRS, article 31(1). It does not apply to sales of goods and products (coefficient 0.15).

If you do not know your coefficient yet, start with the guide to opening activity.

What the 15% rule says

In the simplified regime you do not pay IRS on everything you invoice. With a coefficient of 0.75, only 75% counts as income; the other 25% works like an expense the law assumes you have. But part of that allowance depends on real expenses: the law says the deduction that comes from the coefficients is “parcialmente condicionada” (partly conditional) on expenses actually incurred (CIRS, article 31(13)).

In practice, the calculation works like this:

1. Required amount: 15% of the gross income from services under subparagraphs (b) and (c).
2. Justified amount: the total of the expenses the law accepts (see the next section).
3. If the justified amount is lower, the difference is added to your taxable income. If it is equal or higher, nothing happens.

The first part of the justified amount is automatic: the specific deduction (dedução específica) in CIRS, article 25(1)(a), which is 8.54 × IAS, or €4,587.09 in 2026. So, up to €30,580.60 of services invoiced in the year, the specific deduction is enough on its own (15% × €30,580.60 = €4,587.09). Above that, your invoices start to count.

Instead of the specific deduction, the amount of compulsory Social Security contributions you did not deduct under CIRS, article 31(2) counts, if it is higher. Paragraph 2 only lets you deduct contributions for the part above 10% of gross income; the part up to that 10% is what can count here.

What counts as an expense

According to subparagraphs (a) to (f) of CIRS, article 31(13), the following add up towards the 15%:

• (a) the specific deduction (€4,587.09) or, if higher, the Social Security contributions not deducted under paragraph 2;
• (b) staff costs (salaries) reported to the AT;
• (c) rent for property used in the activity, with an invoice or receipt reported to the AT;
• (d) 1.5% of the taxable property value (valor patrimonial tributário) of property you own and use in the activity (4% for short-term rental, alojamento local, or hotels);
• (e) other purchases of goods and services linked to the activity, on invoices reported to the AT or issued on the Portal das Finanças. The law gives examples: everyday materials, electricity, water, transport and communications, insurance, professional association fees, travel and accommodation;
• (f) imports and intra-EU purchases linked to the activity.

Expenses only partly used for the activity (for example, a mobile phone you also use at home) count at just 25%, under subparagraphs (c), (d) and (e) (CIRS, article 31(14)).

Example: how much more you pay without expenses

Say you invoice €40,000 a year (without VAT) in an activity from the article 151 table, coefficient 0.75. You are in your 3rd year of activity, pay Social Security all year, have no other income and no IRS Jovem, and have €250 of tax deductions (deduções à coleta). The numbers come from the site’s calculator:

If you do not tag any expenses, the €1,412.91 is added to your income: taxable income (rendimento coletável) goes from €28,008.04 to €29,420.95. Estimated IRS goes from €5,244.31 to €5,677.67. In other words, you pay about €433.36 more just for not justifying expenses.

With the same amount in other services (coefficient 0.35), the shortfall is also €1,412.91 and the extra IRS is about €260.66. With €25,000 of invoicing, on the other hand, 15% is €3,750.00, below the specific deduction: the shortfall is €0.00.

The right amount depends on the rest of your return. Try your own numbers in the “Business expenses with an invoice” field of the freelancer tax calculator. Social Security in the example follows the rules of the Social Security calculator.

Step by step on the Portal das Finanças

1. Open e-Fatura on the Portal das Finanças, or use the e-Fatura app or the ATGo app. If you have an activity, you must classify your invoices, because they can be personal or business (AT frequently asked questions, no. 4923).
2. Open Faturação > Adquirente > Resolver Pendências (Invoicing > Buyer > Resolve pending items). When you have an activity, invoices stay “pending” until you say whether they are business expenses and which is the “Atividade de Realização da Aquisição” (the activity the purchase was made for) (nos. 4924 and 4927).
3. For each business invoice, say whether it is fully or partly for the activity and click Guardar (Save).
4. Check the “Despesas da atividade” tab (business expenses) in e-Fatura: that is where you see the invoices you have tagged (no. 4922). If you made a mistake, use Faturação > Adquirente > Verificar Faturas > Alterar (Check invoices > Change) (no. 4928).
5. Do it all by the end of February of the following year (CIRS, article 31(15)(a)). The exact date for 2026 invoices is in the e-Fatura guide.
6. On your IRS return, check table 17 of Annex B (Anexo B). Table 17A includes Social Security contributions (with table 17B giving the NIF of the entity) and imports or intra-EU purchases.
7. Only if the reported amounts are wrong, answer “Sim” (Yes, field 01) in table 17C and enter the totals in fields 17051 to 17054 (staff, rent, other expenses fully or partly for the activity). Rent also requires table 17D. Note: with “Sim”, the AT only considers what you enter in that table, so include all your expenses, even the ones that were already correct (Annex B instructions; CIRS, article 31(16)).

The rest of the return is covered in the guide to filing IRS on recibos verdes.

Common mistakes

• Leaving invoices pending: a business invoice you do not tag does not count towards the 15%.
• Tagging everything as fully business: what you also use in your personal life is partial and only counts at 25%.
• Using an old value for the specific deduction: in 2026 it is €4,587.09 (8.54 × IAS).
• Answering “Sim” in 17C and entering only the missing expenses: with that option, only the amounts in the table count.

Calculate my case with expenses

Frequently asked questions

What is the 15% rule in the simplified regime?

For services with a coefficient of 0.75 or 0.35, you must justify expenses worth 15% of the gross income from those services. Any shortfall is added to your taxable income (CIRS, article 31(13)).

Does the specific deduction count towards the 15%?

Yes. The specific deduction of 8.54 × IAS (€4,587.09 in 2026) always counts or, if higher, the Social Security contributions that were not deducted under article 31(2). Up to €30,580.60 of services a year, that amount is enough on its own.

How much more do I pay if I do not justify expenses?

It depends on your case. In this guide’s example, with €40,000 of services from the article 151 table, the shortfall is €1,412.91 and estimated IRS goes up by about €433.36. Use the calculator with your own numbers.

Does an expense I also use in my personal life count?

It does, but only at 25% of its value, for rent, property and other expenses with an invoice (CIRS, article 31(14)). In e-Fatura, tag it as partly for the activity.

Until when can I tag invoices as business expenses?

Until the end of February of the year after they were issued, on the Portal das Finanças > e-Fatura or in the e-Fatura and ATGo apps (CIRS, article 31(15)(a)).

Can I declare expenses in Annex B instead of e-Fatura?

Yes. In table 17C of Annex B you answer “Sim” (Yes) in field 01 and enter the totals. In that case the AT only considers the amounts in that table, which replace the reported ones, and you must be able to prove them (CIRS, article 31(16)).

Does the 15% rule apply to sales?

No. It only applies to income under subparagraphs (b) and (c) of article 31(1) of the CIRS, that is, services with a coefficient of 0.75 or 0.35.

Official sources

Every figure on this page comes from these sources (official documents, in Portuguese). Updated on 11 November 2026

• CIRS, art.º 31.º — Regime simplificado (Portal das Finanças) (opens in a new window)
• CIRS, art.º 25.º — Dedução específica (8,54 × IAS) (opens in a new window)
• Portaria n.º 480-A/2025/1, de 30 de dezembro (IAS 2026) (opens in a new window)
• Segurança Social — Guia Prático "Novo Regime dos Trabalhadores Independentes" (v1.09, 12/01/2026) (opens in a new window)
• AT — Anexo B do IRS (modelo e instruções do quadro 17) (opens in a new window)
• AT — Perguntas frequentes e-Fatura, adquirentes, faturas (n.os 4922 a 4928) (opens in a new window)