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International Ocean Discovery Program Site U1534 presents an opportunity to study the evolution of subantarctic surface waters in the Atlantic Ocean and investigate Subantarctic Front dynamics during glacial–interglacial transitions. Here we document stable carbon and oxygen isotopes (δ13C and δ18O) in the planktonic foraminifera Globigerina bulloides and Neogloboquadrina pachyderma (sinistral), as well as species abundances of all planktonic foraminifera present in the splice section of Site U1534 interpreted to represent Marine Isotope Stage 11 based on the shipboard stratigraphy. The planktonic assemblage is dominated by N. pachyderma (sinistral), with minor occurrences of other calcareous species; the lowest N. pachyderma (sinistral) abundances suggest the warmest upper ocean temperatures at ~43–44 m core composite depth below seafloor, Method A (CCSF-A). Results demonstrate that δ13C in N. pachyderma (sinistral) and G. bulloides varies from −0.12‰ to 1.01‰ and from 0.19‰ to 1.11‰, respectively. δ18O in N. pachyderma (sinistral) and G. bulloides varies from 1.68‰ to 2.92‰ and from 2.14‰ to 2.97‰, respectively. δ18O values oscillate through the section but are generally lowest near 43–44 m CCSF-A.