Subjective aging predicts various developmental outcomes, including cognitive functioning. However, associations could be bidirectional. We focused on central dimensions of subjective aging (subjective age; self-perceptions of aging related to social losses, physical losses, and ongoing development) and investigated reciprocal longitudinal associations with perceptual-motor speed, both at the between-person level (i.e., Do individuals with more positive subjective aging trajectories exhibit better cognitive performance trajectories?) and within-person level (e.g., Is an individuals' cognitive performance poorer than their typical trajectory on measurement occasions when their subjective aging is less positive than their typical trajectory?). We used data from the German Ageing Survey (n = 15,898; aged 40-95 years; observation period: 2002-2017, up to five occasions; mean number of observations: 2.1; sample sizes between 2002 and 2017: 4,334; 7,668; 4,800; 9,703; 6,551). Using autoregressive latent trajectory models with structured residuals, we controlled for sociodemographic, social, and health-related factors. At the between-person level, higher levels of perceptions related to ongoing development and lower levels of perceptions related to physical and social loss were associated with higher levels of perceptual-motor speed. Linear decline in perceptual-motor speed was less steep for individuals with lower physical loss intercepts and higher ongoing development levels. While there were significant within-person synchronous associations between perceptual-motor speed and subjective aging, we found no reliable cross-lagged associations. All between-person and within-person associations of subjective age with perceptual-motor speed were not statistically significant. Our results imply that there are meaningful between-person and within-person associations between subjective aging and cognitive abilities. (PsycInfo Database Record (c) 2025 APA, all rights reserved).