Pleistocene faunal assemblages are often highly fragmented, hindering taxonomic identifications and interpretive potentials. In this paper, we apply four different methodologies to morphologically unidentifiable bone fragments from the Neanderthal open-air site of Salzgitter-Lebenstedt (Germany). First, we recorded zooarchaeological attributes for all 1362 unidentifiable bones recovered in 1977. Second, we applied zooarchaeology by mass spectrometry (ZooMS) to 761 fragments, and calculated glutamine deamidation values. Third, we assessed the collagen preservation of 30 fragments by near-infrared spectroscopy (NIR) and, finally, we pretreated 10 bones with high predicted collagen values for radiocarbon dating. All returned dates at, or beyond, the limit of radiocarbon dating, indicating an age of older than 51 000 years ago. The ZooMS faunal spectrum confirms a cold environment, dominated by reindeer, alongside mammoth, horse and bison. The low occurrence of carnivore modifications (1%) contrasts with an abundance of human modifications (23%). Cut marks and marrow fractures were observed across reindeer, horse and bison. The mammoth remains are less well preserved and show a lower degree of human modifications, indicating, perhaps, a different taphonomic history. Overall, this study illustrates the importance of retaining, studying and incorporating the unidentifiable bone fraction to optimize interpretations of site formation and subsistence behaviour at Palaeolithic sites.