A challenge for evaluating alcohol treatment efficacy is determining what constitutes a "good" outcome or meaningful improvement. Abstinence at the end of treatment is an unambiguously good outcome; however, a focus on abstinence ignores the potential benefits of patients reducing their drinking to less problematic levels. Patients may be drinking at low-risk levels at the end of treatment but may be high-functioning and impose few social costs. In this study, we estimate the relationship between drinking at the end of COMBINE treatment and subsequent healthcare costs with an emphasis on heavy and nonheavy drinking levels.Indicators of heavy drinking days (HDDs; 5+ drinks for men, 4+ for women) and nonheavy drinking days (non-HDDs) during the last 30 days of COMBINE treatment were constructed for 748 patients enrolled in the COMBINE Economic Study. Generalized linear models were used to model total costs following COMBINE treatment as a function of drinking indicators. Different model specifications analyzed alternative counts of HDDs (e.g., 1 HDD and 2 to 30 HDDs), and groups having Both non-HDDs and HDDs.Patients with HDDs had 66.4% (p