This project aims at exploring possibilities at-using social media data and big data in general for estimating (labour) mobility and migration in the EU. The report is published online. As results were promising, a pilot project will be launched on its basis sometime in 2017. **Feasibility Study:** http://ec.europa.eu/social/main.jsp?catId=738&langId=en&pubId=7910&type=2&furtherPubs=yes This report addresses the question of whether it is technically, financially and legally feasible to estimate geographic mobility and migration flows in the European Union. The study reviews state-of-the-art methods to measure stocks and flows of migrants using traditional data sources but also new and innovative data sources such as mobile phone data and social media data. It finds that it is indeed feasible to estimate geographic mobility and migration flows in the European Union but that that it depends on several important factors such as access to data, legal obstacles and desired outcomes that are outlined in the paper.