This study aimed to investigate the relationship between corporate use of social media and corporate social responsibility (CSR) practices, once Facebook and Twitter are characterized as less costly means of disclosing information, especially non-mandatory ones, like CSR. For this, a descriptive, documentary and quantitative research were carried out through the operation of multiple linear regression, Tobit model, for robust standard errors. The analysis consisted of 360 observations from 2013 to 2017. The main findings showed a positive relationship between corporate use of social media and CSR practices, which was confirmed by the sensitivity test. In addition, the variables of size control, sales growth, return on assets and leverage were also significant, being useful to explain CSR. The results of this study suggest that social media, and more specifically Facebook and Twitter, may be considered as facilitating means for companies to disclose voluntary information, as these channels enable rapid, comprehensive and cost-effective disclosure. Therefore, the research contributes by expanding the literature on the themes through empirical tests that considered aggregate measures of both corporate social media use and CSR.