In 2013⁻2014, nearly 28% of adults in the United States (U.S.) were current tobacco users with cigarettes the most common product used and with nearly 40% of tobacco users using two or more tobacco products. We describe overall change in prevalence of tobacco product use and within-person transitions in tobacco product use in the U.S. between 2013⁻2014 and 2014⁻2015 for young adults (18⁻24 years) and older adults (25+ years). Data from Wave 1 (W1, 2013⁻2014) and Wave 2 (W2, 2014⁻2015) of the Population Assessment of Tobacco and Health (PATH) Study were analyzed (N = 34,235). Tobacco product types were categorized into: (1) combustible (cigarettes, cigars, pipe tobacco, hookah), (2) noncombustible (smokeless tobacco, snus pouches, dissolvable tobacco), and (3) electronic nicotine delivery systems (ENDS). Transitions for individual combustible-product types, and for single- and multiple-product use, were also considered. Overall prevalence of current tobacco use decreased from 27.6% to 26.3%. Among W1 non-tobacco users, 88.7% of young adults and 95.8% of older adults were non-tobacco users at W2. Among W1 tobacco users, 71.7% of young adults transitioned, with 20.7% discontinuing use completely, and 45.9% of older adults transitioned, with 12.5% discontinuing use completely. Continuing with/transitioning toward combustible product(s), particularly cigarettes, was more common than continuing with/transitioning toward ENDS. Tobacco use behaviors were less stable among young adults than older adults, likely reflecting greater product experimentation among young adults. Relative stability of cigarette use compared to other tobacco products (except older adult noncombustible use) demonstrates high abuse liability for cigarettes.