question: BACKGROUND Vaccine market access (VMA) pathways across the European Union (EU) and the United Kingdom (UK) are complex, lengthy, and heterogeneous, particularly when compared with pharmaceuticals. The knowledge base to inform recommendations for optimization of VMA is lacking. We therefore conducted a comprehensive evaluation of EU VMA pathways. METHODS Research in two phases included: (1) mapping VMA pathways in each EU member state (including the UK) based on a literature review, expert interviews, and mathematical archetyping; and (2) interviews with vaccine experts to identify barriers, drivers, and recommendations for regional VMA alignments. RESULTS Key steps in VMA across the EU include horizon scanning, early advice, National Immunization Technical Advisory Group (NITAG) recommendation for inclusion in national immunization programs, health technology assessment (HTA), final decision and procurement. We found significant complexity and heterogeneity, particularly for early advice, and in the roles, decision-making criteria, and transparency of NITAGs and HTA bodies. The most important drivers for rapid VMA included demonstration of disease burden and vaccine benefit (e.g., efficacy, safety, economic). Key barriers were budget limitations and complexity/clarity of VMA processes (e.g., need for national-regional consensus, clarity on process initiation, and clarity on the role of HTA). Recommendations for alignment at EU and member-state levels include information sharing, joint clinical assessment, initiatives to address funding and political barriers, and improved transparency by decision-making bodies. Early engagement with vaccine stakeholders was a key recommendation for manufacturers. CONCLUSIONS There is significant potential for alignment, collaboration, and improvement of VMA across the EU. Roles, responsibilities, and transparency of key bodies can be clarified. The COVID-19 pandemic response should stimulate policies to improve access to all vaccines, including routine ones, and form the foundation upon which a consistent vaccine ecosystem can be created for the EU, one that is resilient, consistent between member states, and fit for purpose.