This dataset presents benthic foraminiferal trace element ratios (i.e., B/Ca, U/Ca, Mn/Ca, U/Mn, Al/Ca, Fe/Ca) measured on the epibenthic foraminifera Cibicides kullenbergi at sediments from International Ocean Discovery Program Site 383-U1540 (55° 8.47ʹ S, 114° 50.52ʹ W, 3580 m) during Marine Isotope Stage 11. The samples were reductively cleaned and to determine the uncertainty of the analyses, two full replicates were analyzed. For all except one sample the C. kullenbergi Al/Ca ratios were below the limit of detection (LOD), at 0.5 µmol/mol. The element ratios were measured at the Institute of Geosciences at Kiel University (Kiel, Germany) using an Agilent 7900 inductively coupled plasma-mass spectrometer (ICP-MS). The degree of carbonate ion saturation (Δ[CO₃²⁻]) in bottom waters was calculated using the calibration of Yu and Elderfield (2007, doi:10.1016/j.epsl.2007.03.025).