This study compared reports of alcohol consumption using an Interactive Voice Response (IVR) system and the Timeline Followback (TLFB). One hundred eighty-two daily smokers who were not alcohol dependent provided once daily reports of alcohol consumption using an IVR system and participated in a weekly TLFB interview. The reporting time period was 7 days after participants attempted to quit smoking as part of participation in a smoking cessation clinical trial. The results revealed moderate to high correlations between reports of drinking behavior as assessed by IVR and TLFB. Reporting biases for both IVR and TLFB were approximately equal, with a slight trend toward underreporting drinking on the TLFB. Compliance with the IVR system was poor. This study provides preliminary evidence that it is possible to use an IVR system for the assessment of alcohol use in smokers participating in a clinical trial, and IVR seems to adequately assess drinking behavior in those that use the system. However, future studies should focus on improving compliance with IVR in this population.