A significant part of CO2 emissions stem from the mobility sector. This contribution examines various approaches to greenhouse gas accounting in commuter traffic and business travel in the university context. A questionnaire was developed, tested and used to analyse the mobility habits of commuting students and employees. The business travel data as well as the logbooks of the university’s own fleet of vehicles are analysed for two complete years. For the investigated university, emissions for commuting surpasses by far those from the business travel. The results deliver insights on where to start when conceiving measures to reduce the carbon footprint from mobility. Additionally, a comparison of business travel volume before and after the pandemic highlights how traditional mobility behaviour has changed due to the pandemic-induced disruption A detailed analysis of the effort deployed during the gathering, processing and evaluation of the different data streams is presented. On this basis, the contribution emphasises that digitisation and automation of the whole process is a fundamental requirement for enabling regular, quantitative reporting.