CIRS

CIRS is the legislation. IRS is the tax. When a freelancer in Portugal says they "pay IRS," they mean the tax defined by the Código do Imposto sobre o Rendimento das Pessoas Singulares.

For most freelancers, the practical entry point into CIRS is Article 151 and the table of activity codes it refers to.

CIRS vs CAE: two different systems

This distinction causes more confusion than almost anything else in Portuguese freelancer registration.

The CIRS activity code comes from the table attached to Article 151 (approved by Portaria 1011/2001 and applied by AT, the tax authority). It classifies professional income: the liberal and technical services a trabalhador independente (independent worker) provides.

CAE (Classificação Portuguesa de Atividades Económicas) is the national classification of economic activities, now in its CAE-Rev.4 version. For an individual it classifies business income, such as selling goods. A company uses CAE codes only, whatever it does: when a Lda forms, its CAE codes follow from its business purpose.

So the two systems are not "one for individuals, one for companies". An individual can hold one or both: a freelancer who only provides professional services may have just a CIRS code, while one who also sells goods holds a CAE as well. A programmer, for example, can be registered under CIRS code 1332 (programadores informáticos) and CAE 62100 (atividades de programação informática). The numbers are different in each system and are not interchangeable.

For a freelancer, it is the CIRS code and the work actually done, not the CAE, that drive the coefficient and the withholding rate. See the CAE glossary entry for the CAE side.

What Art. 151 governs

Article 151 of CIRS is one sentence: it refers to a table of activities approved by portaria of the Minister of Finance. That table (Portaria 1011/2001, Anexo I) gives each professional activity a code. Whether your activity is specifically listed in it decides your simplified-regime (regime simplificado) coefficient, which is the multiplier AT applies to your gross revenue to calculate taxable income. What counts is the work you actually do, not just the code you registered.

Named professions in the Art. 151 table carry the 0.75 coefficient: 75% of gross revenue is taxable, 25% is treated as assumed business costs. This applies to programmers (code 1332), consultants (1320), architects, engineers, lawyers, accountants, doctors, and most other listed professions.

The catch-all code for activities not specifically named is code 1519 ("outros prestadores de serviços," other service providers). Its coefficient is 0.35: only 35% of gross revenue is taxable. In raw numbers it looks more favorable, but using it when a specific code applies to your activity is a misclassification.

Common Art. 151 codes for tech and creative freelancers

Code	Activity (PT)	Activity (EN)	Coefficient
1332	Programadores informáticos	Programmers	0.75
1313	Analistas de sistemas	Systems analysts	0.75
1320	Consultores	Consultants	0.75
1336	Designers	Designers	0.75
1519	Outros prestadores de serviços	Other service providers	0.35

For a full breakdown of how CIRS 1332 specifically works for programmer-freelancers in Portugal, including the expat-specific cross-border obligations, see CAE vs CIRS: what activity code do you actually need as a programmer?

The coefficient and what it means

Under the simplified regime, AT doesn't ask you to prove your expenses item by item. Instead, it assumes a fixed percentage of your gross revenue went to business costs and taxes you on the rest.

For a programmer on code 1332, earn €40,000 in a year and AT starts from €30,000 of taxable income (75%). The other €10,000 is the assumed expense deduction. That figure applies from your third tax year, or from the start if you also earn employment or pension income or closed an activity in the last five years; otherwise the coefficient is reduced in your first two years. Either way it assumes your documented expenses pass the check below.

If your documented expenses fall short, the shortfall is added back to taxable income. You need to show 15% of gross services income in documented expenses (invoices with your NIF in the e-fatura system), but an automatic specific deduction of roughly 4587,09 € (2026) counts toward that threshold, or your Social Security contributions up to a cap of 10% of your gross, whichever is larger. At income under roughly €30,580, you may not need to show any additional expenses. Foreign supplier invoices never reach e-Fatura, and whether they count depends on where they come from: purchases from another EU country are declared separately in Anexo B, while services bought from outside the EU are an open question.

See regime simplificado for the full mechanics including first-year discounts and the organized-accounting threshold.

CIRS vs CIRC

CIRS governs personal income tax (individuals). CIRC (Código do Imposto sobre o Rendimento das Pessoas Coletivas) governs corporate income tax (companies). If you operate as a sole proprietor, CIRS applies. If you form a Lda or Unipessoal Lda, CIRC applies to the company and CIRS applies to income you extract from it (salary, dividends).

The two codes have separate simplified regimes, separate coefficients, and separate rate tables. Running a company and running a sole proprietorship are not the same tax situation, even when the underlying commercial activity is identical.