Annual corporate income tax return (declaração Modelo 22)
Fixed date
Filed to
The Autoridade Tributária e Aduaneira, by electronic transmission of data through the Portal das Finanças. Article 120 of the Corporate Income Tax Code sets the date in absolute terms: the return «deve ser enviada, anualmente, por transmissão electrónica de dados, até ao último dia do mês de Maio,» «independentemente de esse dia ser útil ou não útil.» A company that has adopted a tax period other than the calendar year does not use that date: paragraph 2 sends it to «o último dia do 5.º mês seguinte à data do termo desse período», again whether or not that day is a business day. The balance of the tax rides on the same deadline rather than on a date of its own, because article 104 puts the final payment «Até ao último dia do prazo fixado para o envio da declaração periódica de rendimentos», so a return filed on time without the money is not the duty discharged.
Who it applies to
Every entity in the jurisdiction
The taxpayers that article 117 of the same code makes subject to the periodic income return, which in practice means every company resident in Portugal and every permanent establishment of a non-resident entity. There is no turnover floor below which the return stops being owed: a company that traded nothing in the year still has a tax period and therefore still has a filing window. Article 117 does carve out cases in which the return is not required of certain exempt entities; those exceptions were not read in a primary source for this entry, so the scope above is stated as the general rule and not as an exhaustive one.
Deadline
31 May, every year. A calendar date fixed by statute, independent of the financial year.
Extensions and exceptions: The statutory date is the last day of May, and that is the date printed above. It has nonetheless been moved later, year after year, by a despacho of the Secretary of State for Tax Affairs, and the Tax Authority's own fiscal calendar for 2026 shows the annual Modelo 22 not in May but in June: «DURANTE O MÊS E ATÉ AO DIA 30 DE JUNHO». An extension of that kind is announced during the year and carries no promise for the next one, so it is not something to plan against: work to the last day of May and treat any later date as a reprieve that has to be confirmed on the Tax Authority's own calendar for the year in question.
If missed
The general tax offences regime applies rather than a penalty inside the income tax code. Article 116 of the Regime Geral das Infrações Tributárias punishes the absence of a return, or its submission after the legal deadline, with a fine «de € 150 a € 3750». The range is what the article prints; where inside it a particular case falls is not something this entry states, and the reductions and aggravations that the same regime attaches to negligence, to voluntary regularisation and to repeat conduct were not read in a primary source here. Nothing is asserted about interest on the tax itself, which is a separate matter from the fine for the late return.
Proof of filing
The comprovativo de entrega that the Portal das Finanças returns for the submitted Modelo 22, carrying the identification of the return, the tax period it covers and the date and time of submission, together with the payment document generated for the balance and the proof that it was paid. Keep the approved accounts the return was built from alongside it, since those are what the figures must reconcile to if the return is later reviewed.