This study investigates the benefits to human health that would occur in the United States (U.S.) due to reductions in local air pollutant emissions stemming from a federal policy to reduce greenhouse gas emissions (GHG). In order to measure the impacts of reduced emissions of local pollutants, this study considers a representative U.S. climate policy. Specifically, the climate policy modeled in this analysis is the Warner-Lieberman bill (S.2191) of 2008 and the paper considers the impacts of reduced emissions in the transport and electric power sectors. This analysis provides strong evidence that climate change policy in the U.S. will generate significant returns to society in excess of the benefits due to climate stabilization. The total health-related co-benefits associated with a representative climate policy over the years 2006 to 2030 range between $90 and $725 billion in present value terms depending on modeling assumptions. The majority of avoided damages are due to reduced emissions of SO2 from coal-fired power plants. Among the most important assumptions is whether remaining coal-fired generation capacity is permitted to backslide up to the Clean Air Interstate Rule (CAIR) cap on emissions. This analysis models two scenarios specifically related to this issue. Co-benefits increase from $90 billion, when the CAIR cap is met, to $256 billion if SO2 emissions are not permitted to exceed current emission rates. On a per ton basis, the co-benefit per ton of GHG emissions is projected to average between $2 and $14 ($2006). The per ton marginal abatement cost for the representative climate policy is estimated at $9 ($2006).