Proportionality, pivotal to EU regulations and Solvency II, tailors rules to insurers’ size and complexity. Inconsistent application by supervisory authorities (NSAs) necessitates clarity to prevent undue costs. This study examines the issue via a review of the literature and industry discussions, emphasizing Solvency II’s introduction of proportionality and the varied interpretations it evokes. Transparent communication is crucial, and regulatory evolution must align with market dynamics, with the European Insurance and Occupational Pensions Authority (EIOPA) fostering convergence. Assessing proportionality mandates a comprehensive evaluation of an insurer’s nature, scale, and complexity. Regulatory distinctions between first-party and third-party risks could enhance market efficiency. Ultimately, a holistic, market-oriented approach is essential for proportionate regulation in the insurance sector, requiring concerted efforts to elucidate frameworks, foster transparency, and align regulatory evolution with market dynamics.