The Physical Activity Guidelines for Americans, second edition was released in 2018 and recommends adults do 150 minutes/week of moderate-intensity equivalent aerobic physical activity preferably spread out over a week (adult aerobic guideline). Assessing awareness and knowledge of the guideline is important for monitoring public understanding of physical activity and health. PURPOSE: To describe prevalence and correlates of reported awareness and knowledge of the aerobic guideline among US adults. METHODS: National data from the 2019 FallStyles survey were analyzed. Adults (n=3471) who reported seeing, hearing, or reading anything about governmental physical activity guidelines in the last year were considered aware of the guidelines. Adults who selected 150 minutes spread out over a week when asked about the minimum amount of moderate-intensity physical activity the government recommends for substantial health benefits were considered knowledgeable of the adult aerobic guideline. Weighted prevalence and adjusted odds ratios from logistic regression models were estimated. RESULTS: Overall, 9.2% of adults reported being aware of the guidelines and 2.9% knew the aerobic guideline, though 27.5% selected 30 minutes/day, 5 days/week, which is one way to meet the guideline. After adjusting for covariates, the odds of awareness were higher with older age, higher education level, and among married adults (bivariate differences by income no longer significant). Adults who were aware of the guidelines had higher odds of knowing the guideline (bivariate differences by education, income, and meeting the guideline no longer significant).