||Corporate social responsibility regarding CO2 emission reduction has gained grounds as an integrated part of organizations. To present the sustainability efforts made by the organization, many of the largest corporations publish annual corporate social responsibility (CSR) reports to engage with their stakeholders. In this study, we address the questions to what extent organizations report about sustainability of their corporate real estate portfolio to stakeholders, which indicators they use to report and which characteristics of the organization influence the reported indicators. This is studied based on a content analysis of CSR reports of 2014. The reports of a random sample of 200 organizations of the 500 largest organizations in the world are analysed. Interviews with corporate real estate managers of a smaller sample of key organizations are carried out to complement the quantitative analysis with qualitative information about underlying reasons and practices. Logistic regression is used to relate differences in reporting tendencies to characteristics of the organization. The results indicate that, apart from the more frequently used indicators as energy consumption, GHG emissions, water consumption and waste, indicators as renewable energy, supply chain management and community engagement are also topics frequently addressed by the organizations. However, we find significant differences in reporting content that can be related to organization characteristics. The amount of employees has the biggest positive influence on reporting of CRE sustainability indicators. Furthermore, significant differences related to market capitalization, geographic region (Europe versus US) and industrial sector are found. The interviews provide an indication that the reporting and implementation of sustainability measures are often misaligned: not reporting CRE sustainability indicators does not mean that the measures are not implemented within the organization. The interviewed organizations are often implementing sustainability on an ad-hoc basis which could explain the lack of reporting in the CSR reports.We argue that a form of standardization of CSR reporting could help to increase transparency and benchmark a company’s sustainability performance regarding CREM, but that such a standard is still a rather remote goal as long as many organizations have not reached a mature state in terms of CREM in general and sustainable CREM in particular.