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Predicted intense and prolonged drought events challenge forest management. Thinning is debated as a silvicultural measure for reducing drought risk in densely established forest stands. We report on a thinning experiment in a 26-year-old Norway spruce stand (Picea abies), comprising of two thinning intensities and one unthinnned control. The removal of 43% (moderate thinning, MT) and 67% (heavy thinning, HT) of the initial basal area led to increased water availability during the entire three year observation period. Stand-level transpiration (E_s) was decreased by about 25% upon moderate, and by about 50% upon heavy thinning during the first year after the interventions had been carried out. However, differences in E_s across the treatments decreased within three years after thinning mainly due to increased single-tree transpiration and additional understory evapotranspiration at HT. Nevertheless, due to …