MOMENTUM Routine Immunization Transformation and Equity implemented localization strategies through NGOs for community engagement in conjunction with government vaccination teams to universalize COVID-19 vaccination uptake up to the last mile in India. This journal article discusses the strategies and collaboration that resulted in reaching close to 50 million beneficiaries through messaging and facilitated the administration of more than 14 million vaccine doses, including 6.1 million doses for vulnerable and marginalized communities in 18 States and Union territories in India, along with suggesting implications for public health practice and research.