Evolução da tributação do rendimento de pessoas singulares em Portugal

Abstract

In recent years, the taxation of personal income in Portugal, especially the Individual Income Tax (IRS), has undergone several reforms. This dissertation aims to investigate the evolution of the Individual Income Tax (IRS) in Portugal, focusing on legislative changes and the fiscal impact on disposable income. Thus, the underlying research of this study explores the transformations in the taxation system over the years: 2013, 2015, and 2023, to understand how changes in IRS rates, tax deductions, and income brackets have financially affected various family compositions. The presented study consists of two parts: a theoretical analysis and a practical, simulated application. The theoretical part includes an introduction to the topic and its historical evolution. The practical application focuses on analysing various cases through simulations of different family compositions, calculating the tax in the selected years to determine the respective effective tax rates and their fiscal evolution. It is concluded that over the past ten years, there has been a reduction in IRS rates and some occasional tax cuts, but the net gains for taxpayers are considered minimal, especially when compared to inflation and the loss of purchasing power.

Date of Award	20 Oct 2025
Original language	Portuguese
Awarding Institution	Universidade Católica Portuguesa
Supervisor	Luísa Anacoreta (Supervisor)