PurposeCorporate social responsibility (CSR) reporting has been theorized as a key communication device and an integral part of a broader stakeholder integration management strategy. This paper aims to examine the relationship between CSR disclosures and organized labor, an important internal stakeholder, whose institutional role in dynamically advancing employee interests creates opportunities and challenges for strategic management and firm sustainability.Design/methodology/approachBy using a sample of 2,526 US firm-year observations for the period 2002–2015, the authors demonstrate that managers in unionized contexts are more likely to issue CSR reports than managers in firms, where labor is not organized.FindingsThe authors demonstrate that managers in unionized contexts are more likely to issue CSR reports than managers in firms where labor is not organized. Considering stakeholder theory, they argue that, in unionized contexts, managers more intensively resort to CSR disclosures to form an alignment of interests, develop collaborative bonds with unions and smoothen relationships with external financial stakeholders. This effect is more prominent in areas where corporate spatial clustering and the prevailing political ideology facilitate the role of unions.Research limitations/implicationsFirst, the data refer to USA, which may limit the generalization of the results. Hence, researchers could use cross-country datasets to overcome this limitation. Second, it would be important to know what benefits are enjoyed by the unionized companies that issue CSR reports. Third, they acknowledge that there is useful qualitative information they do not analyze. This analysis could potentially relate specific CSR information to unions’ needs and demands. Further, there are alternative channels through which companies disclose relevant information such as 10-K filings, annual reports, firm websites, media, public announcements, etc. These are not captured by the data.Practical implicationsManagers could benefit from the empirical analysis, which suggests that through the initiation of CSR reports a dialogue with unions is greatly facilitated. Managers should consider that CSR reports reduce information asymmetries and may attract the interest of investors. Unionists should be aware that CSR reports constitute an opportunity to identify mutual interests and align goals. Business analysts, investors and shareholders should be aware that standalone CSR reports are used by managers to reduce information asymmetries and disparities with unions and to communicate an investment-friendly context. So, market participants should factor such policies by unionized firms into their investment analyses.Social implicationsThe authors offer implications for managers, labor unionists and market participants.Originality/valueThis paper examines the relationship between CSR disclosures and organized labor, an important internal stakeholder, whose institutional role in dynamically advancing employee interests creates opportunities and challenges for strategic management and firm sustainability.