Objective Cognitive tests are used repeatedly to assess the treatment response or progression of cognitive disorders. The Montreal Cognitive Assessment (MoCA) is a valid screening test for mild cognitive impairment. The aim of our study was to establish 90% reliable change indices (RCI) for the MoCA together with the Mini‐Mental State Examination (MMSE) in cognitively healthy older adults. Method We analyzed 197 cognitively healthy and functional independent volunteers aged 60–94 years, who met strict inclusion criteria for four consecutive years. The RCI methods by Chelune and Hsu were used. Results For 1, 2, and 3 years, the 90% RCI for MoCA using Chelune's formula were −4 ≤, ≥4; −4 ≤, ≥4 and −5 ≤, ≥4 points, respectively, and −3 ≤, ≥3 for the MMSE each year. Ninety percent RCI for MoCA using Hsu's formula ranged from −6 to 0, respectively, and +3 to +8 dependent on the baseline MoCA. Conclusion Our study demonstrated RCI for the MoCA and MMSE in a 3‐year time period that can be used for the estimation of cognitive decline or improvement in clinical settings. Copyright © 2016 John Wiley & Sons, Ltd.