Introduction: The right to social security is established as a fundamental human right, financed through a contributory system with the participation of public and private sector workers, employers, and the State. However, disparities exist regarding the contribution burden imposed on employees: while the private sector contribution rate is set at 9.45%, public sector employees contribute 11.45%, despite being enrolled under the same pension system and accessing identical benefits. Objectives: The general objective of this research is to examine the compatibility of the legal framework governing mandatory social security contributions for public and private sector workers with the principle of equality in Ecuador. Methodology: Methodologically, this study adopts a descriptive-analytical, dogmatic-legal approach based on the examination of statutory frameworks, legal doctrine, and case law, applying the parameters of the equality test developed by the Constitutional Court of Ecuador. Results: The findings demonstrate an unjustified percentage disparity in social security contribution rates between public and private sector employees, imposing a higher contributory burden on civil servants. In the absence of supporting evidence such as actuarial studies or objective technical criteria for this differentiation, the resulting asymmetry lacks proportionality and reasonableness, thereby directly violating the principle of equality before the law and the guarantee of non-discrimination in accessing this right. Discussion: The discussion evaluates how the percentage differentiation in employee and employer contributions administratively established by the Board of Directors of the Ecuadorian Social Security Institute (IESS) on grounds of institutional governance and financial sustainability must conform to constitutional review. Since public and private employees are in an analogous de jure and de facto position under the general social security regime, the doctrine and jurisprudence of the Constitutional Court demand the strict application of the equality and proportionality test, demonstrating that the regulatory powers of the IESS cannot establish discriminatory treatment without an objective, reasonable, and constitutionally valid justification. Conclusions: Public and private sector workers constitute comparable legal subjects within the social security system. Consequently, the distinction in contribution rates fails to meet the legal standards of suitability, reasonableness, and proportionality, raising critical concerns regarding its compatibility with the constitutional principle of equality. General area of study: Law. Specific area of study: Constitutional. Type of article: Narrative bibliographic review.