During the coronavirus pandemic, it was imperative that real-time, rapidly changing guidance on continuously evolving critical health information about COVID-19 be communicated. This case study highlights how understandable and actionable COVID-19 health information was systematically developed and disseminated to support highly vulnerable refugee, immigrant, and migrant (RIM) communities in Clarkston, Georgia. Our approach was grounded in community-based participatory research (CBPR) incorporating Cultural and Linguistically Appropriate Services (CLAS) standards, plain language and health literacy guidelines, and health communication science to improve the understandability and usability of COVID-19 micro-targeted messaging for RIM communities. We followed a centralized systematic approach to materials development and incorporated local needs and existing networks to ensure cultural and linguistic responsiveness as well as understandability for populations with limited literacy skills. Further, iterative development of materials with community members and agencies provided buy-in prior to dissemination. As part of a multi-pronged community-wide effort, effective materials and messaging provided support to community health workers and organizations working to improve vaccination rates among the RIM community. As a result, we saw vaccine rates in Clarkston outpace other similar areas of the county and state due to this community-wide effort.