Hydrogen isotopic compositions of C37 long chain alkenones (δ2HC37) have been proposed as a proxy for past seawater salinity and applied in several regions. However, previous studies were based solely on a single core and often suggested unlikely large changes in salinity. Here we present a new δ2HC37 record, in combination with oxygen isotopes of benthic foraminifera from the same samples, from a sediment core from the Chilean margin (ODP site 1235). The observed negative shift in δ2HC37 of 20‰ during deglaciation was identical to that of the nearby located, but deeper, ODP core 1234 (Weiss et al., 2019), suggesting a regionally consistent shift in δ2HC37. Here we present an isotope dataset spanning 0.15-94.43 mbsf. The age model of Haettig et al., 2023 covers the last 40.000 years spanning 0.15-49.50 mbfs.