AbstractSocial context plays an important role in alcohol consumption. While most studies focus on explicit social drinking norms, this study aimed to (1) develop an implicit social attunement (ISA) task to experimentally assess how willingness to drink alcohol is affected by social alcohol drinking (SAD), social non-alcohol drinking (SNAD), and social non-drinking (SND) settings and peer feedback on willingness to drink in these settings, and (2) assess how ISA is associated with explicit social attunement, age, alcohol use and related problems. Participants (N = 506) aged 16–60 years completed the ISA task and questionnaires assessing alcohol use and alcohol use–related problems, age, and explicit social attunement online. Willingness to drink was highest in the SAD setting (SAD: M(SD) = 5.70 (2.68); SNAD: M(SD) = 4.03 (2.20); SND: M(SD) = 2.02 (1.30)) and—regardless of social setting—lower peer willingness to drink induced higher ISA than higher peer willingness to drink (SAD: t(325) = − 2.929, p = .035; SNAD: t(325) = − 2.888 p = .036; SND: t(325) = − 6.764, p < .001). Higher ISA to higher peer willingness in the SAD (r = .15, p = .001) and SNAD (r = .11, p = .011) settings was associated with higher alcohol use and related problems, while higher ISA to lower peer willingness in the SND setting was associated with lower alcohol use and related problems (r = − .18, p = .002) and recent alcohol use (standard drinks: r = − .14, p = .011; binge drinking days: r = − .16, p = .005). Explicit social attunement, but not ISA, mediated the association between lower age and higher alcohol use and related problems (b = − .013, p = .009). Results indicate that peer feedback can be a protective or risk factor for alcohol use, depending on the social setting. Future studies are needed to elucidate differences between implicit and explicit social attunement behaviors in their associations with age and alcohol use and related problems.