This study examines on the association between the accountability and economic performance of Portuguese hospital entities after the entry into force of the new Public Accounting Standards, taking into account stakeholder theory, legitimacy theory, and institutional theory. Furthermore, we investigate whether accountability, underlying procurement, and other entity operations act differently in public and private hospitals. For this purpose, we collected data for 56 Portuguese hospital entities in the period from 2018 to 2022. We conducted a quantitative analysis, testing the hypotheses using econometric regressions estimated with panel data. The results show a reduction in the return on assets for both sectors. Our evidence suggests that being a public hospital entity harms economic performance. In this sector, size and gender positively affect economic performance. Still, the level of provisions negatively affects it. In contrast, in private hospital entities, the determinants of their economic performance are the number of directors (with a negative impact) and provisions (with a positive one). These results show that when hospital entities are committed to governance structures and social responsibility, or environmental, social, and governance (ESG) factors underlying sustainability strategies, they can enhance their performance. This article contributes by collecting evidence on the effect of accountability on the performance of public hospital entities, the features of which tend to be different from those of private hospital entities.