Abstract Background Subjective cognitive decline (SCD), i.e., the self-perceived feeling of worsening cognitive function, may be the first notable syndrome of preclinical Alzheimer’s disease and other dementias. However, not all individuals with SCD progress. Stability of SCD, i.e., repeated reports of SCD, could contribute to identify individuals at risk, as stable SCD may more likely reflect the continuous neurodegenerative process of Alzheimer’s and other dementias. Methods Cox regression analyses were used to assess the association between stability of SCD and progression to MCI and dementia in data derived from the population-based Leipzig Longitudinal Study of the Aged (LEILA75+). Results Of 453 cognitively unimpaired individuals with a mean age of 80.5 years ( SD = 4.2), 139 (30.7 %) reported SCD at baseline. Over the study period ( M = 4.8 years, SD = 2.2), 84 (18.5 %) individuals had stable SCD, 195 (43.1 %) unstable SCD and 174 (38.4 %) never reported SCD. Stable SCD was associated with increased risk of progression to MCI and dementia (unadjusted HR = 1.8, 95 % CI = 1.2–2.6; p