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Estimates of material properties such as ice content or unfrozen water content are critical for thermal modelling of the response of permafrost to climate forcing, understanding contaminant flow and transport, or for predicting the behaviour of permafrost as an engineering substrate. We utilize time-lapse electrical resistivity surveys to examine the potential for imaging relative changes in unfrozen water content for cold continuous permafrost in the Canadian Arctic. Electrical resistivity data were collected from 2012/08 to 2015/06 at semi-regular time intervals using a permanent electrode installation at Iqaluit International Airport in Iqaluit, Nunavut. Using postinversion model differencing, we observe significant changes in electrical resistivity and we infer changes in unfrozen water content that appear consistent with temperature records. The most prevalent changes in resistivity are not limited to the active layer, but extend from 1–8 m depth in a zone of significant temperature fluctuation.