A history of heavy drinking increases vulnerability to, and the severity of, Alzheimer’s Disease (AD) and related dementias, with Alcohol Use Disorder (AUD) identified as the strongest modifiable risk factor for early-onset dementia. Heavy drinking has increased markedly in women over the past 10 years, with mature adult women reporting a 41% increase in heavy drinking days during the coronavirus (COVID-19) pandemic. This raises concern over the impact of excessive alcohol consumption during mature adulthood on dementia-related outcomes in both the short- and long-term. As a first pass attempt at addressing this issue, the present study employed isogenic and congenic female and male mature adult (5-9 months of age) C57BL/6J (B6J) mice to examine how a 1-month history of alcohol intake under modified Drinking-in-the-Dark (DID) procedures (10, 20,40% alcohol v/v) alters spatial and working memory. In both a genetically and experientially heterogeneous cohort of mice and in an isogenic