The Affordable Care Act provides states with the opportunity to develop health benefit exchanges structured marketplaces for the purchase of health insurance coverage by small employers and individual purchasers. The law provides an array of design choices to the states in an effort to allow the exchanges to reflect varying preferences across the country. This analysis uses the Health Insurance Policy Simulation Model (HIPSM) to delineate the cost and coverage implications of a standard implementation of the ACA in New York compared to the no reform case, along with the differential effects of a number of alternative design options.