Aim This study aims to evaluate the reliability and validity of the Turkish version of the Standard Assessment of Global Everyday Activities (SAGEA) scale in older adults. Methods The study employed a cross-sectional, methodological design. The SAGEA scale was administered twice, with a two-week interval for test-retest reliability. The study examined correlations between the SAGEA and other functional measures including the Activities of Daily Living (BADL), Instrumental Activities of Daily Living (IADL), the Timed Up and Go Test (TUGT), and the Mini-Mental State Examination (MMSE). Results The participants were 307 community-dwelling older adults who underwent a comprehensive geriatric assessment at a university hospital. The average age of the participants was 74.93 years. SAGEA scores showed strong correlations with BADL (−.620), IADL (−.802), TUGT (.613), and MMSE (−.784). The Cronbach alpha for internal consistency was .79, and the test-retest reliability was high (r=.99, p<.001). Conclusion The Turkish version of SAGEA (TSAGEA) is a quick, reliable, and validated scale that can be easily used in clinical practice without additional training. It effectively assesses both physical and cognitive functionality in older adults, aiding in early intervention and disability prevention.