The US significantly outspends all other top 10 developed nations, with no increase in life expectancy. Increasing transparency in healthcare spending could help address this cost to outcomes gap.  CMS’ recent release of Medicare Part B Utilization and Payment data, covering 880,000 providers and $77 billion in Medicare payments, is a significant step toward this goal. OBJECTIVES:  Understand differences in billed versus paid amounts for provider and procedure types reported in Medicare data. METHODS: Descriptive and inferential statistics were run on provider specialties representing greater than 2% of claims to describe the differences between maximum allowed Medicare payment amount, amount billed by providers, and the amount reimbursed.  Geographical variation was also explored. RESULTS: Amount billed is at least double the amount paid and double the maximum allowable amount for all of the specialties explored; amount billed versus paid varies significantly by specialty, with some specialties billing as much as six times what they are paid. Largest discrepancies were in anesthesiology (on average billing $838, versus $139 allowed and $110 paid). Other specialties with significant disparity include cardiology, diagnostic radiology, emergency medicine, ophthalmology, and orthopedic surgery; within certain specialties, specific procedures showed ranges of billing and payment ratios; across all specialties, average amount paid was about 90% of maximum allowable; and each state is represented in line with census data for the Medicare population; state differences in amount paid versus billed and allowed is not significant. CONCLUSIONS: In analyzing payer and provider data to increase transparency on healthcare spend, we recognize there is heterogeneity between what is paid versus billed across specialty.  There is an opportunity to focus attention on narrowing this gap for high-value procedures through evidence and education of patients, payers, and providers to ensure patients receive appropriate treatment, and providers are appropriately reimbursed.