In recent years, the CSR disclosure–firm risk relationship has raised the acute interest of capital providers, regulators, debtholders, and academic researchers. In addition to the mounting corporate social responsibility (CSR) disclosure issues, one particular area that has increasingly attracted the attention of academics, practitioners, and policymakers is the dynamic of CSR disclosure. The effects of institutional pressures and the relative nature of reputation have amplified expectations over time, resulting in a dynamic CSR disclosure strategy to meet those expectations. However, studies on the relationship between CSR disclosure and firm risk over time are still in their premature stages. Thus, this paper seeks to contribute to the literature on firm risk and CSR disclosure by examining the effect of ESG disclosure on the cost of capital over time. The study examines a sample of 430 S&P 500 US firms observed over the 2011 to 2019 period. Our results indicate that the three dimensions do not have the same effect. Governance disclosure decreases the cost of capital during the first years, and in later years, the effect becomes positive. Over time, social disclosure increases the cost of capital. However, environmental disclosure shows a negative and significant effect on the cost of capital during the first years but no significant effect later in time. Our results contribute to explaining the dynamic effect of CSR disclosure. A predominant feature to consider is the evolution of CSR disclosure over time. Steadily, US firms are moving away from some CSR disclosure activities to others. However, firms that abandoned some existing CSR disclosure commitments may face aggressive responses from stakeholders. US firms have to be more cautious when linking CSR disclosure to firm risk over time, recognizing the long-term benefits and drawbacks of CSR disclosure.