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Research Highlights: novel fast and easily assessable proxies for vulnerability to cavitation of conifer sapwood are proposed that allow reliable estimation at the species level. <i>Background and Objectives:</i> global warming calls for fast and easily applicable methods to measure hydraulic vulnerability in conifers since they are one of the most sensitive plant groups regarding drought stress. Classical methods to determine <i>P</i>₁₂, <i>P</i>₅₀ and <i>P</i>₈₈, i.e., the water potentials resulting in 12, 50 and 88% conductivity loss, respectively, are labour intensive, prone to errors and/or restricted to special facilities. Vulnerability proxies were established based on empirical relationships between hydraulic traits, basic density and sapwood anatomy. Materials and Methods: reference values for hydraulic traits were obtained by means of the air injection method on six conifer species. Datasets for potential <i>P</i>₅₀ proxies comprised relative water loss (RWL), basic density, saturated water content as well as anatomical traits such as double wall thickness, tracheid lumen diameter and wall/lumen ratio. <i>Results:</i> our novel proxy <i>P</i>_25W, defined as 25% RWL induced by air injection, was the most reliable estimate for <i>P</i>₅₀ (<i>r</i> = 0.95) and <i>P</i>₈₈ (<i>r</i> = 0.96). Basic wood density (<i>r</i> = −0.92), tangential lumen diameters in earlywood (<i>r</i> = 0.88), wall/lumen ratios measured in the tangential direction (<i>r</i> = −0.86) and the number of radial cell files/mm circumference (CF/mm, <i>r</i> = −0.85) were also strongly related to <i>P</i>₅₀. Moreover, CF/mm was a very good predictor for <i>P</i>₁₂ (<i>r</i> = −0.93). Conclusions: the proxy <i>P</i>_25W is regarded a strong phenotyping tool for screening conifer species for vulnerability to cavitation assuming that the relationship between RWL and conductivity loss is robust in conifer sapwood. We also see a high potential for the fast and easily applicable proxy CF/mm as a screening tool for drought sensitivity and for application in dendroecological studies that investigate forest dieback.