From shopping malls to office buildings, walking in a commercial building that feels vastly over-cooled has become almost normal in the United States. In this short communication, we estimate the cost of over-cooling commercial buildings for the United States. Using 2012 data from the US Energy Information Administration (EIA) and simulating data with the Department of Energy's (DOE) eQuest software package, we calculated an energy cost of 103,929 GWh, an environmental cost of 57,125 kt CO(2)e, and a financial cost of $10B, which approximately represent a loss of 8%. The problem of over-cooling is therefore substantial and solving it would offer significant energy, environmental, and financial savings. (C) 2015 Elsevier B.V. All rights reserved.