Objectives: This secondary analysis evaluated opioid-specific validation results of the Tobacco, Alcohol, Prescription Medication, and Other Substances (TAPS) tool for screening in primary care. Methods: This study is a secondary data analysis of the TAPS validation study. Performance of the TAPS tool for screening for unhealthy opioid use (with a score of 1+ for heroin and/or prescription opioids representing a positive screen) was evaluated. Discriminative ability was examined in comparison with reference standard measures across the spectrum of unhealthy opioid use: timeline follow-back with and without oral fluid testing identifying past-month use and the modified Composite International Diagnostic Interview for past-year problem use, opioid use disorder (OUD), and moderate-severe OUD. Results: In a sample of 2000 primary care patients, 114 screened positive for opioids on the TAPS tool. With a TAPS cutoff equal to 1+, the TAPS accurately identified past-month use, problem use, any OUD, and moderate-severe OUD (sensitivities = 68%-85%, specificities = 97%-98%, area under the curve = 0.80-0.91). When past-month use was expanded to include timeline follow-back with oral fluid testing,