This study isolated the effect of whole head submersion in cold water, on surface heat loss and body core cooling, when the confounding effect of shivering heat production was pharmacologically eliminated. Eight healthy males were studied in 17 °C water under four conditions; the body was either insulated or uninsulated, with the head either above the water or completely submersed in each body-insulation sub-condition. Shivering was abolished with buspirone (30 mg) and meperidine (2.5 mg/kg) and subjects breathed compressed air throughout all trials. Over the first 30 minutes of immersion exposure of the head increased core cooling both in the body-insulated conditions (head-out: 0.47±0.2°C, head-in: 0.77±0.2°C, p=0.05) and the body-exposed conditions (head-out: 0.84±0.2°C and head-in: 1.17±0.5°C, p<0.02). Submersion of the head (7% of the body surface area) in the body-exposed conditions, increased total heat loss by only 8%. In both body-exposed and body-insulated conditions, head submersion increased core cooling rate much more (39%) than it increased total heat loss. This may be explained by a redistribution of blood flow, in response to stimulation of thermosensitive and/or trigeminal receptors in the scalp, neck and face, where a given amount of heat loss would have a greater cooling effect on a smaller perfused body mass. In 17°C water the head does not contribute relatively more than the rest of the body to surface heat loss; however a cold-induced reduction of perfused body mass may allow this small increase in heat loss to cause a relatively larger cooling of the body core.