This study involved healthy community-living older adults in an investigation of the association between moderate alcohol consumption (AC) and acute changes in postural stability and whether the association differed according to pre-AC balance skills. Thirty-nine moderate drinkers aged ≥ 65 years (62% women; mean age: 73.9 ± 6.1 years) consumed a moderate dose of alcohol (0.4 g/kg; administered as two drinks). Breath alcohol concentration and postural stability were measured at five time points (pre-AC and 40, 80, 120, and 160 minutes post-AC) using unipedal stance time (UPST) and center of pressure (CoP) displacement. Pre-AC UPST was used to categorize participants into good-balance (≥30 seconds) and poor-balance (<30 seconds) groups. Peak breath alcohol concentration was 30 mg/dL at 40 minutes post-AC. For all participants, postural stability declined significantly at 80 minutes post-AC (UPST, p = .005; anterior–posterior CoP displacement, p = .029). While the poor-balance group did not show a significant decrease in UPST duration over the course of the study, the good-balance group experienced significant decline at 80 minutes compared with baseline (p < .001) and remained above the 30-second UPST cutoff. Both groups experienced similar worsening in anterior–posterior CoP displacement at 80 minutes post-AC. Thus, moderate AC was associated with acute decline in postural stability in older adults. The worsened anterior–posterior CoP displacement post-AC in the poor-balance group was of particular concern because these participants were already at lower balance functioning pre-AC. Larger, more representative studies of varying groups of participants are needed to further explore how this change relates to fall incidents and fall risk.