Background: This article seeks to inform state and local school food policies by evaluating the impact of Connecticut's Healthy Food Certification (HFC), a program which provides monetary incentives to school districts that choose to implement state nutrition standards for all foods sold to students outside reimbursable school meals. Methods: Food service directors from all school districts participating in the National School Lunch Program (NSLP) (N = 151) in Connecticut were surveyed about the availability of competitive foods before and after the 2006-2007 implementation of HFC. Food categories were coded as healthy or unhealthy based on whether they met the Connecticut Nutrition Standards. Data on NSLP participation were provided by the State Department of Education. Changes in NSLP participation and availability of unhealthy competitive foods in elementary, middle, and high schools were compared pre- and post-HFC across districts participating (n = 74) versus not participating (n = 77) in HFC. Results: On average, all districts in Connecticut reduced the availability of unhealthy competitive foods, with a significantly greater reduction among HFC districts. Average NSLP participation also increased across the state. Participating in HFC was associated with significantly greater NSLP participation for paid meals in middle school; however, implementing HFC did not increase overall NSLP participation beyond the statewide upward trend. Conclusion: The 2006-2007 school year was marked by a significant decrease in unhealthy competitive foods and an increase in NSLP participation across the state. Participation in Connecticut's voluntary HFC further reduced the availability of unhealthy competitive foods in local school districts, and had either a positive or neutral effect on NSLP participation. (Contains 4 tables and 1 figure.)