Background <p>Laparoscopic cholecystectomy (LC) is one of the most commonly performed minimally invasive surgical procedures. Postoperative pain may negatively affect patient satisfaction and recovery. External oblique intercostal plane block (EOIB) is proposed as a new regional anaesthesia technique to reduce this pain. The aim of this study was to investigate the effect of ultrasound-guided EOIB on postoperative pain scores, postoperative opioid consumption, intraoperative hemodynamic parameters, and patient satisfaction in patients undergoing LC.</p> Methods <p>After approval of the ethics committee, 64 patients aged 18–65 years, in ASA I-II class, who underwent elective LC for cholelithiasis were included in the study. Patients were randomly allocated into two groups: the EOIB group and the control group. Visual analogue scale (VAS), heart rate, systolic-diastolic-mean arterial pressure, analgesic consumption, nausea-vomiting frequency and patient satisfaction parameters were recorded for 24&#xa0;h postoperatively.</p> Results <p>VAS scores were significantly lower in favour of EOIB at all time points (<i>p</i> &lt; 0.001). There was a significant difference over time and between groups. (<i>p</i> &lt; 0.001) In addition, patient satisfaction was significantly higher in the EOIB group at 24&#xa0;h (<i>p</i> &lt; 0.001).</p> Conclusions <p>EOIB improves pain control after LC, reduces the need for analgesics and significantly improves patient satisfaction.</p> Trial registration <p>ClinicalTrials.gov, NCT06712498; registered 26 November 2024 (retrospectively registered).</p>