In 2020, drug overdose deaths in the U.S. increased nearly 30%, with the majority linked to opioids and specifically, fentanyl. Reducing fentanyl overdoses requires a multi-pronged approach which includes communication efforts for those at-risk about ways to reduce their risk. We will discuss findings from research studies designed to inform harm reduction messaging in Illinois and Washington State. Using interviews and focus groups with both teens and adults, we identified knowledge gaps as well as a pervasive perception that pills obtained from friends or familiar dealers were safe and unlikely to be laced with fentanyl. This allowed at-risk individuals to believe they were not at-risk for overdose. Messaging approaches must personalize the risk of overdose, empathize rather than judge, and provide clear, explicit harm reduction steps that individuals can take. Examples of effective messaging strategies will be shared.