Background and Aims: Acute pain management in drug addicts is a critical yet understudied topic. Drug addicts have a decreased pain threshold, impairing anaesthetic pain control. This study aimed to evaluate the postoperative quality of recovery in addicts and non-addicts after receiving erector spinae plane block (ESPB) with general anaesthesia. Methods: Sixty males, aged 18‑60 years, with an American Society of Anesthesiologists physical status I/II, scheduled for elective lumbar decompression surgery, were divided into two equal groups. Group A included 30 addicts and group N included 30 non-addicts. Both groups received bilateral ultrasound‑guided ESPB with 20 mL bupivacaine (0.25%) before induction of general anaesthesia. The primary outcome was comparison of the 24‑hour postoperative quality of recovery (QoR‑15) score. The secondary outcomes were time to first analgesic requirement, postoperative pain scores, morphine consumption, and adverse events. Results: The QoR‑15 score was higher in group N (median = 128.5, interquartile range = 107‑136) than in group A (118 [99‑130]), indicating a better recovery in group N. The visual analogue scale pain score was lower in group N than in group A, especially in the first 12 hours postoperatively. Time to first analgesic request was significantly longer in group N than in group A (mean ± standard deviation: 8.67 ± 2.74 and 5.53 ± 1.64 hours, respectively, P =0.001), Morphine consumption was significantly higher in group A than in group N (9.62 ± 3.2 and 7.08 ± 2.57 mg, respectively, P =0.041). Conclusion: Drug addicts experienced decreased analgesic efficacy of ESPB compared to nonaddicts, with comparable postoperative QoR‑15 score following lumbar decompression surgery.