This document provides a description of the methodology for the calculation of institutional (HEI-level) indicators in the European Higher Education Sector Observatory (EHESO). The corresponding data can be downloaded through the EHESO Microdata Access and are used for the EHESO Institutional Benchmarking Tool (EHESO-BMT). The specific calculations for the BMT are described in a companion handbook. For each type of data, the handbook provides information on the indicator definition, the way it is calculated and any specific rules.