The objective of this study is to analyse corporate factors that explain the presentation of sustainability reports under GRI4 guidelines in Ibero-America. It starts with a descriptive analysis of the companies and then goes on to carry out an empirical study through a logistic regression analysis (logit) from which the corporate factors that influence the level of adherence to the information contained in the reports reported during the period under study are identified. The conclusion is that the number of organizations seeking to standardize their sustainability reporting process, using the GRI guidelines, is increasing and the decision to achieve better levels of adherence to its guidelines is determined by the size of the company, the sector to which it belongs, the assurance of the reports and the listing of its securities on the stock market. The contribution consists of observing the growth of interest in report writing and the characteristics that influence the adherence to GRI guidelines as a standard of recognized informative quality at a world level. The study highlights the importance of voluntary reporting of sustainability activities.