BACKGROUND AND AIM: Disparities in COVID-19 are stark: in California, incidence and mortality rates in Hispanics range from 50% higher to triple those of non-Hispanic whites. In fall, 2020, the US National Institutes of Health funded existing Centers to address these gaps domestically, under the RADx-UP program (Rapid Acceleration of Diagnostics for Underserved Populations), which focuses on COVID testing in underserved or vulnerable communities. In collaboration with community organizations, our aim is to overcome barriers to testing among Hispanics in four California counties, increase testing, and reduce viral spread. METHODS: Community members identified barriers and strategies were devised to address them. The UC Davis RADx-UP team deployed mobile COVID antigen test sites, targeting predominantly Hispanic areas in the California central valley. All tests are free, drop-ins are welcome, and no health insurance information is collected, addressing economic, internet, and uninsured status barriers. A majority bilingual UCD staff and members of trusted community organizations open testing on weekends and evenings, when most test sites are closed. The rapid antigen test provides results within 15 minutes, which vastly increases potential to curtail asymptomatic spread by the recent contacts of an individual who tests positive. We also provide public health education, post-test counselling, and referrals for services. RESULTS:During ramp-up we conducted 744 tests, with 82% Hispanic, 53% females, and a mean age of 39, range: 1 to 89. Current positivity rate is 4.6%, with one-fourth being asymptomatic. On two occasions, one person tested positive and called family and friends who showed up to be tested, thereby identifying clusters of cases. We are also partnering with vaccine providers and encouraging vaccine uptake. CONCLUSIONS:Targeted testing and education is expected to help narrow the disparities in COVID-19 incidence and mortality. With the vaccine roll-out, continued efforts will strive to reduce the disproportionate casualties among Hispanics. KEYWORDS: Disaster response, health disparities, community partnerships