Objective <p>This study aims to assess the current status of sanitation facilities across primary healthcare institutions in China, offering valuable insights for improving sanitary facilities in middle-income settings.</p> Methods <p>Data were draw from the ACACIA project (March 2021-April 2023) across seven provinces in China. A total of 2139 visits were made to 1167 primary healthcare institutions. Unannounced standardized patients (USPs) were utilized to covertly assess the sanitation facilities during clinical visits.</p> Results <p>Toilet sanitation facilities were available in 70.4% of visits. 95% had access to piped water. The probability of having a handwashing sinks in toilet and examination room is 79.2% and 50.8%. Significant regional disparities were observed, with southern regions exhibiting higher facility coverage compared to northeastern regions. Public primary healthcare institutions have more sanitary facilities than private ones. Higher-tier institutions have higher rates of sanitary facilities. Regarding quality, adverse event rates show minimal differences between clinic-level and center-level institutions. And the urban institutions is obviously better than that in rural areas.</p> Conclusions <p>China’s policy initiatives have improved sanitation facilities within primary healthcare institutions, but gaps persist in essential components and maintenance. Continued efforts are needed to enhance sanitation infrastructure to meet higher standards and ensure comprehensive coverage. The study’s insights can inform both domestic and global strategies for improving healthcare sanitation, contributing to the achievement of international health goals. Future research should focus on identifying barriers to sanitation improvements and developing targeted interventions to standardize sanitary facilities in primary healthcare settings.</p>