This study aims to analyze the results of open access publishing policies established for projects funded by the European Union's Horizon 2020 programme. It specifically seeks to identify specific publication requirements, quantify the number of peer-reviewed articles published in open access, and analyze the number of documents deposited in institutional repositories. The archive of Horizon 2020 project publications provided by the EU Publications Office was used as a database. It was possible to determine the reported peer-reviewed publications. From those with DOIs, the data were cross-checked with the OpenAIRE platform to analyze open access and repository information. From the original data, a total of 206,400 peer-reviewed articles are observed, of which 202,102 have a DOI, 4,269 include the publication’s ISSN, and only 29 have no data to reach access. Cross-referencing the data from those with DOIs in OpenAIRE, it is shown that a total of 126,154 of these articles have no metadata. This analysis highlights the need to improve the tracking of the access address of publications.