From the early 2000s onwards, the rise in net lending of the non-financial corporate sector has contributed substantially to the increase in the German current account surplus. The main driving factor behind the development in the non-financial corporate sector’s net lending was a rise in savings (retained earnings) while business investment was comparatively stable. To shed light on the determinants of corporate savings, this study presents results from an analysis using firm-level data from the recently developed Bundesbank database Janis. The descriptive analysis suggests that the increase in corporate savings was a widespread development across the corporate sector in Germany. In line with aggregate results, also the median firm saw an increase in profitability while dividends were subdued. Empirical results show that firms with initially higher leverage ratios increased their saving ratios more after the year 2001, providing arguments for a role of a desire to deleverage in explaining increased corporate savings. No (unanimous) evidence is found that increases in uncertainty and market power of firms affect corporate savings positively.