Background: In combination with systematic routine screening, brief alcohol interventions have the potential to promote population health. Little is known on the optimal screening interval. Therefore, this study pursued 2 research questions: (i) How stable are screening results for at-risk drinking over 12 months? (ii) Can the transition from low-risk to at-risk drinking be predicted by gender, age, school education, employment, or past week alcohol use?. Methods: A sample of 831 adults (55% female; mean age = 30.8 years) from the general population was assessed 4 times over 12 months. The Alcohol Use Disorders Identification Test—Consumption was used to screen for at-risk drinking each time. Participants were categorized either as low-risk or at-risk drinkers at baseline, 3, 6, and 12 months later. Stable and instable risk status trajectories were analyzed descriptively and graphically. Transitioning from low-risk drinking at baseline to at-risk drinking at any follow-up was predicted using a logistic regression model. Results: Consistent screening results over time were observed in 509 participants (61%). Of all baseline low-risk drinkers, 113 (21%) received a positive screening result in 1 or more follow-up assessments. Females (vs. males; OR = 1.66; 95% confidence intervals [95% CI] = 1.04; 2.64), 18- to 29-year-olds (vs. 30- to 45-year-olds; OR = 2.30; 95% CI = 1.26; 4.20), and those reporting 2 or more drinking days (vs. less than 2; OR = 3.11; 95% CI = 1.93; 5.01) and heavy episodic drinking (vs. none; OR = 2.35; 95% CI = 1.06; 5.20) in the week prior to the baseline assessment had increased odds for a transition to at-risk drinking. Conclusions: Our findings suggest that the widely used time frame of 1 year may be ambiguous regarding the screening for at-risk alcohol use although generalizability may be limited due to higher-educated people being overrepresented in our sample.