Essential Tax Deadlines 2026: VAT, Corporate Tax, IES and Other Obligations
By Hugo Ribeiro, Certified Accountant · Member of the Order of Certified Accountants · HVR Business Consulting
<h2 id="introducao">Introduction: The Strategic Importance of the 2026 Tax Calendar for Business Management</h2> <p>Navigating the complex Portuguese tax landscape demands precision, planning, and a deep understanding of legal obligations. For any entity, be it a small or medium-sized enterprise (SME) or a large corporation, timely and rigorous compliance with its tax responsibilities is not merely a matter of legal conformity, but a critical component of its financial health and market reputation. Delays in submitting declarations, omissions of information, or late payments …
Key Takeaways
Monthly VAT: declaration by 20th, payment by 25th of the 2nd following month
Model 22 (Corporate Tax): deadline by May 31st of the following year
IES: deadline by July 15th of the following year
Advance payments: July (33%), September (33%), December (34%)
Late penalties range from €30 to €22,500 depending on severity
FAQ
What is the deadline for monthly VAT declaration?
The monthly VAT periodic declaration must be submitted by the 20th of the 2nd month following the relevant period. Payment must be made by the 25th of the same month.
When should I submit Model 22?
Model 22 (annual corporate tax return) must be submitted by the last working day of May of the following year.
What is the deadline for IES?
The Simplified Business Information (IES) must be submitted by July 15th, for companies with fiscal year matching calendar year.
When are the corporate tax advance payments due?
Corporate tax advance payments are divided into three installments: 1st by July 31st (33%), 2nd by September 30th (33%) and 3rd by December 15th (34%).
What are the consequences of late tax filing?
Delays result in late interest (4% per year), fines from €30 to €22,500 depending on severity, and possible loss of tax benefits for loss-making companies.