Here, we present a new record of SST for the time interval 30 to 17 Ma derived from the long‐chain alkenone unsaturation ratio uk'37 and TEX 86 at Integrated Ocean Drilling Program Site 1406A in the midlatitude North Atlantic. Results confirm that warm temperatures from 24°C to over 30°C prevailed in midlatitudes in this time and suggest a transition from colder early‐middle Oligocene to warmer average conditions after 24.5 Ma. Complex and temporally varying relationships are observed between North Atlantic SST and benthic δ18O in paired samples. Significant covariation is only observed around the Oligocene‐Miocene transition, coincident with a lower average marine ice extent. These North Atlantic temperature records provide a new context in which to examine the stability of climate and the Antarctic ice sheet during the Oligocene and early Miocene.