To conduct a randomized, controlled trial of abstinence-contingent recovery housing delivered with or without intensive day treatment among individuals exiting residential opioid detoxification. Random assignment to one of three conditions: recovery housing alone (RH), abstinence-contingent recovery housing with reinforcement-based treatment RBT (RH + RBT) or usual care (UC). RH and RH + RBT participants received 12 weeks of paid recovery housing contingent upon drug abstinence. RH + RBT participants also received 26 weeks of RBT, initiated concurrently with recovery housing. Assessments were conducted at 1, 3 and 6 months after treatment enrollment. Out-patient drug-free substance abuse treatment program in Baltimore, Maryland. Patients (n = 243) who completed medication-assisted opioid detoxification. Primary outcome was drug abstinence (opioid- and cocaine-negative urine and no self-reported opioid or cocaine use in the previous 30 days). Secondary outcomes included abstinence at all time-points (1, 3 and 6 months), days in recovery housing and employment. Overall rates of drug abstinence were 50% for RH + RBT, 37% for RH and 13% for UC (P < 0.001). At 6 months, RH + RBT participants remained more likely to meet abstinence criteria than UC participants (37% versus 20%, P = 0.016). Length of stay in recovery housing mediated abstinence outcomes and was longer in RH + RBT (49.5 days) than in RH (32.2 days; P < 0.002). Abstinence-contingent recovery housing improves abstinence in opioid-dependent adults following medication-assisted detoxification. The addition of intensive 'reinforcement-based treatment' behavioural counseling further improves treatment outcomes, in part by promoting longer recovery house stays.