Laparoscopic cholecystectomy is one of the most common surgical procedures. Even though there is less postoperative pain with laparoscopic cholecystectomy than with open cholecystectomy, severe pain can occur, particularly within the first 24 hours. Evaluation of the efficacy of ultrasound-guided interfascial plane blocks for postoperative analgesia of laparoscopic cholecystectomy has recently come to prominence. The aim of our study was to compare the postoperative analgesic efficacy of thoracoabdominal nerves block through perichondrial approach (TAPA) and modified-TAPA (m-TAPA) blocks in patients who underwent laparoscopic cholecystectomy. The present study included 56 patients who underwent laparoscopic cholecystectomy under general anesthesia and received TAPA or m-TAPA block for perioperative analgesia. Each patient signed a written informed consent form. Block times and numerical rating scale (NRS) scores 1, 2, 3, and 12 hours postoperatively, hourly and total tramadol amount of use via the patient-controlled analgesia device, and additional analgesic drug consumption were all recorded. The TAPA group had significantly longer block application times than the m-TAPA group. At 1 and 12 hours, NRS scores were lower in the TAPA group. However, the mean NRS scores, total tramadol use, and use of additional analgesics were comparable between the groups. TAPA and m-TAPA block methods reduced NRS scores by alleviating pain after laparoscopic cholecystectomy procedures, thereby reducing the need for additional analgesics. Block times for TAPA were significantly longer than those for m-TAPA. However, both block applications were completed in a short period, smoothly and safely. The analgesic effect of TAPA block was more distinctive at 1 and 12 hours, and NRS scores were lower. However, we think that both block methods, when used under ultrasound guidance, will provide effective analgesia by supplementing the multimodal analgesia planned for laparoscopic cholecystectomy and other abdominal operations.