Background: Spontaneous adverse event reporting systems support post-marketing adverse event detection. Regulatory authorities provide public data access, but practices vary. Objectives: To compare public data provision practices for spontaneous adverse event reporting systems in Korea, the United States (US), the European Union (EU), and Japan, focusing on accessibility and scope. Methods: Each authority’s website, guidelines, and access policies were reviewed across four domains: eligibility, data fields, narrative data, and cost. Results: For eligibility, the US and Japan had no public dataset access restrictions, whereas Korea limited access to institutions and required request submission and review. For data fields, the US and Japan provided standardized data fields, whereas fields varied by stakeholder group in Korea and the EU. Narrative data were available via Freedom of Information Act (FOIA) requests in the US. The EU provided narrative data via the EudraVigilance web application at Levels 2B and 3 for pharmacovigilance purposes. Korea and Japan provided no narrative data. Public datasets were free in all systems, although US FOIA requests could incur search, review, and duplication fees. Conclusion: Data provision differed across the four authorities in eligibility requirements and data scope. These findings may serve as a comparative reference for each authority’s pharmacovigilance data provision practices.