According to the European Single Electronic Format (ESEF) mandate that came into force in January 2020, companies in EU-regulated markets are required to prepare annual reports in the digital xHTML format. Companies preparing consolidated financial statements using IFRS accounting standards are also required to tag their disclosures using the ESEF XBRL Taxonomy.
In Phase 1 of the ESEF mandate, companies were to tag only their financial statement disclosures in XBRL. From Phase 2, they also need to tag the notes to financial statements. The ESEF mandate also has an audit requirement that each EU-member country is allowed to formulate on its own.
Mandatory implementation of ESEF had to be pushed back by one year because of the adverse effect of the pandemic on EU economies. However, many EU companies decided to voluntarily file their ESEF reports despite an option to postpone compliance. Austria, the Czech Republic, Germany, and Slovenia did not allow their companies a one-year delay.