Transformative cell and gene therapies have now launched worldwide, and many potentially curative cell and gene therapies are in development, offering the prospect of significant health gains for patients. Access to these therapies depend on decisions made by health technology assessment (HTA) and payer organizations. We sought to describe the emerging cell and gene therapies market access landscape by analyzing 17 US commercial payer medical policies, and HTA reports from five European countries and Canada. We found that some US health plans applied coverage restrictions more often than others (four plans applied restrictions in all decisions, while four plans applied restrictions in <30% of decisions). The European and Canadian HTA bodies recommend access to fewer therapies than US health plans, reflecting a more stringent approach in the context of limited evidence and high scientific uncertainty that is commonly associated with these treatments. Our findings suggest that patient access to approved cell and gene therapies is restricted in all regions studied, though the nature of these restrictions differs between US health plans and the European/Canada HTA recommendations. Payers, HTA groups, pharmaceutical companies, and other stakeholders should collaborate to more clearly define the “uncertainties” and develop market access policies that balance benefits of early access with ongoing data collection to close evidence gaps over time.