Continued escalation in health care expenditures in the United States has led to an unsustainable model that consumes almost 20% of GDP. Policymakers have recognized the need for industry reform and have taken action through the passage of the Affordable Care Act (ACA). The purpose of this quantitative, longitudinal study was to examine the relationship between the type of health insurance and health care costs. Mechanism theory and game theory provided the theoretical framework. The analysis of secondary data from the Healthcare Cost and Utilization Project included a sample of 1,956,790-inpatient hospital stays from 2007 to 2014. Results of one-way ANOVAs indicated that between 2% and 9% of health care costs could be attributed to type of health insurance, a statistically significant finding. Results also supported the effectiveness of the ACA in stabilizing health care costs. The average annual rate of health care cost increase was 38.6% from 2007 until 2010, decreasing to an average annual increase of 4.3% from 2011 until 2014. Results provide important information to generate positive social change for consumers, providers, and policymakers. This includes improving decisions related to health care costs, improved understanding of the costs of health care services, increased transparency, increased patient engagement, maximizing consumer utility, facilitation of reduction of waste within the industry, and increased understanding of the impact of health policy on health care costs and efficiencies within newly created health policies. Results may also improve transparency of health care costs, which allows consumers, providers, and policymakers to take specific action to reduce health care costs, resulting in a more just and sustainable health care model.