Background: In Germany, out-of-pocket payments (OOPP) account for a large proportion of total health expenditure. However, there are only few investigations on how morbidity-related, sociodemographic and lifestyle factors affect OOPP particularly in the older population. The aim of this study was to identify factors affecting OOPP for health care services among elderly Germans in a longitudinal setting. Methods: This longitudinal study used data from 2 follow-up waves (3-year interval) from a population-based prospective cohort study (ESTHER study) collected in Saarland, Germany. At the first follow-up wave, subjects were between 57 and 84 years old. Participants provided comprehensive data including individual OOPP for the preceding 3 months. Fixed effects (FE) regressions were used to determine factors affecting OOPP. Results: Mean individual OOPP (3-month period) rose from € 119 (first wave) to € 136 (second wave). Longitudinal regressions showed that higher morbidity did not affect OOPP. Moreover, changes in sociodemographic as well as lifestyle factors were not related to changes in OOPP. Solely, exemption of OOPP reduced the dependent variable significantly. Conclusion: In contrast to cross-sectional findings for Germany, OOPP are not related to morbidity and income in this study. This underlines the complex nature of OOPP in old age and the need for longitudinal studies to gain some insight into the underlying causal factors.