This study investigated the stability of extreme response style (ERS) and acquiescence response style (ARS) over a period of 8 years. ERS and ARS were measured with item sets drawn randomly from a large pool of items used in an ongoing German panel study. Latent-trait-state-occasion and latent-state models were applied to test the relationship between time-specific (state) response style behaviors and time-invariant trait components of response styles. The results show that across different random item samples, on average between 49% and 59% of the variance in the state response style factors was explained by the trait response style factors. This indicates that the systematic differences respondents show in their preferences for certain response categories are remarkably stable over a period of 8 years. The stability of ERS and ARS implies that it is important to consider response styles in the analysis of self-report data from polytomous rating scales, especially in longitudinal studies aimed at investigating stability in substantive traits. Furthermore, the stability of response styles raises the question in how far they might be considered trait-like latent variables themselves that could be of substantive interest.