Background: Data on COVID-19-induced disruption to routine vaccinations in the South-East Asia and Western Pacific regions (SEAR/WPR) have been sparse. This study aimed to quantify the impact of COVID-19 on routine vaccinations by country, antigen, and sector (public or private), up to 1 June 2020, and to identify the reasons for disruption and possible solutions. Methods: Sanofi Pasteur teams from 19 countries in SEAR/WPR completed a structured questionnaire reporting on COVID-19 disruptions for 13–19 routinely delivered antigens per country, based on sales data, government reports, and regular physician interactions. Data were analysed descriptively, disruption causes ranked, and solutions evaluated using a modified public health best practices framework. Findings: 95% (18/19) of countries reported vaccination disruption. When stratified by country, a median of 91% (interquartile range 77–94) of antigens were impacted. Infancy and school-entry age vaccinations were most impacted. Both public and private sector healthcare providers experienced disruptions. Vaccination rates had not recovered for 39% of impacted antigens by 1 June 2020. Fear of infection, movement/travel restrictions, and limited healthcare access were the highest-ranked reasons for disruption. Highest-scoring solutions were separating vaccination groups from unwell patients, non-traditional vaccination venues, virtual engagement, and social media campaigns. Many of these solutions are under-utilised. Interpretation: COVID-19-induced disruption of routine vaccination was more widespread than previously reported. Adaptable solutions were identified which could be implemented in SEAR/WPR and elsewhere. Governments and private providers need to act urgently to improve coverage rates and plan for future waves of the pandemic, to avoid a resurgence of vaccine-preventable diseases. Funding: Sanofi Pasteur. Declaration of Interests: At the time of the preparation of this work, Rebecca C Harris, Yutao Chen, Pierre Côte, Antoine Ardillon, Maria Carmen Nievera, Kiruthika Velan Kandasamy, Kuharaj Mahenthiran, Ta-Wen Yu, Changshu Huang, Clotilde El Guerche-Séblain, Juan C Vargas-Zambrano, Ayman Chit, and Gopinath Nageshwaran were employees of Sanofi Pasteur and might be shareholders of Sanofi. Anna Ong-Lim and Somasundaram Aiyamperumal have no disclosures. Poh Chong Chan reports speaker fees and other fees for involvement in clinical trial from Sanofi Pasteur. Ethics Approval Statement: As the study did not gather patient or individual level data or involve any interventions, formal ethical approval was not sought. Data were mostly open source or company data, and informed consent was sought from those filling in the survey