Key dates to consider
March 10
Submission of the SAF-T (PT) billing file, in accordance with Ordinance n.º 321-A/2007, and Rectification Declaration n.º 2-A/2017, of February 2, which amend Ordinance n.º 302/2016, of December 2, modifying the data structure of the file referred to in Ordinance n.º 321-A/2007, of March 26.
March 20
Date concentrating several relevant tax obligations, including:
Payment of withholding taxes on Personal Income tax -IRS- and Corporate Income Tax -IRC, in accordance with Articles 98.º of the Personal income tax Code and 94.º of the Corporate Income Tax Code.
Submission of the periodic VAT declaration (monthly regime), as provided in Article 41.º of the VAT Code (mandatory for companies whose turnover in the previous year is equal to or greater than €650,000, with any changes to be communicated in January).
Payment of quarterly VAT, when applicable.
Submission and payment of the Monthly Stamp Duty Declaration, corresponding to the month following that in which the tax obligation arose, in accordance with Article 44.º of the Stamp Duty Code.
Other relevant Corporate Income Tax – IRC- dates
May 31, 2026
Submission of the Modelo 22 of Portuguese Corporate Income Tax -IRC- declaration for the 2025 fiscal year, in accordance with Article 120.º of the IRC Code.
Payment of the IRC determined in the declaration.
The declaration must be submitted exclusively online via the Tax Authority Portal.
When a company closes its accounts on a date other than December 31, the principle remains the same, but the dates are adjusted. The logic guiding the calendar is that the final IRC payment occurs after the fiscal year is closed and the tax calculated, and the declaration must be submitted by the last day of the 5th month following the end of the period.
July, September, and December, 2026
Payments on Account (PC) of Portuguese Corporate Income Tax -IRC, which act as advances on the tax due for the current fiscal year.
These payments follow the structure of the fiscal year, not only the calendar year.
July 15, 2026
Submission of IES/DA – Simplified Business Information, relating to the 2025 accounts.
Note: exceptional extension of deadlines
It should be noted that, following exceptional measures adopted by the Government, Order SEAF n.º 7/2026 – XXV, of 7/02, regarding the calamity situation in certain areas of the country (the list of 68 affected municipalities can be found in Resolution of the Council of Ministers n.º 15-B/2026, of January 30, and in Resolution of the Council of Ministers n.º 15-C/2026, of February 1), the extension of certain tax deadlines until April 30, 2026 was admitted, without interest or penalties.
According to guidance issued by the Tax and Customs Authority, this extension may cover, among others, obligations related to VAT filings and payments, withholding taxes on Personal Income tax- IRS – and Corporate Income tax- IRC, Stamp Duty, and other periodic tax obligations.
Belzuz Advogados, S.L.P., Department of Tax Law, provides continuous legal and tax support, helping companies comply with all these obligations, anticipate deadlines, and benefit from exceptional regimes, such as the extension of deadlines in areas affected by calamity until April 30, 2026, without interest or penalties.