Abstract: This data set measures methane concentrations in ancient air trapped in the West Antarctic Ice Sheet (WAIS) Divide and Greenland Ice Sheet Project (GISP2) ice cores; presenting two, high-resolution ice core methane records of the past 2500 years, one from each pole. These measurements were used to reconstruct the methane Inter-Polar Difference (IPD) during the late Holocene. Also included are model results of methane emissions that were presented in the manuscript describing this data set.