This empirical study investigates determinants of interstate living-cost differentials for the year 2005. It seeks to supplement existing related studies, most of which have investigated such differentials but at the metropolitan area or county levels and for earlier time periods. OLS and two-stage least squares (2SLS) results imply that the overall cost of living in a state is positively a function of per capita income and the relative amount of shoreline on major bo-dies of water, and negatively a function of the presence of right-to-work laws, heating degree days, and toxic chemical releases. Interestingly, the 2SLS estimate adopts two additional amenity/dis-amenity variables (population density and crime rate) as instrumental variables.