This dataset consists of glacial and Mid-Holocene multi-species benthic δ18O mean data from cores that form depth transects at Cape Hatteras and Blake Outer Ridge. The mean δ18O for each core was derived by averaging multiple monospecific measurements from different depth intervals corresponding to the MH or LGM. The standard error is σ/√n; where σ is the multi-species replicate error at either CH or BOR across both time periods, and n is the number of species analysed at each core. Stable isotope measurements were performed using a VG Isogas SIRA mass spectrometer with Multicarb preparation system (>80 μg) and a Thermo MAT253 isotope ratio mass spectrometer with Kiel IV carbonate preparation device (<80 μg) at the Godwin Laboratory, University of Cambridge. δ18O and δ13C are reported relative to the Vienna Peedee belemnite (VPDB) standard, and for both instruments analytical precision is estimated to be better than ±0.07 ‰ and ±0.04 ‰ respectively. Where foraminiferal abundances were low and/or bulk sediment was scarce or unavailable, we also supplemented our data with published δ18O data. This file also contains glacial sortable silt mean grain size data for a limited number of cores from both transects. Samples were processed using established methods (McCave et al., 1995) and analyzed at University College London on a Beckman Coulter Multisizer using the Enhanced Performance Multisizer 4 beaker and stirrer to ensure full sediment suspension. Two or three separate aliquots were analyzed for each sample, sizing 70,000 particles per aliquot. Full procedural error based on replicates starting from newly sampled bulk sediment was ±0.32 μm (n=10). Glacial mean sortable silt values were calculated by averaging data from sediments corresponding to between 19 and 23 ka BP. The standard error is σ/√n; where σ is the standard deviation of glacial measurements for each core, and n is the number of glacial measurements for each core.