Reducing distribution losses in low-voltage networks remains a key operational priority for PT PLN (Persero) ULP Alas. This study investigates the effectiveness of distribution transformer tap optimization and grounding system reinforcement as a combined approach to improving voltage quality and reducing technical losses. The transformer tap was adjusted at Distribution Substation AL114 from position 5 (19.0 kV) to position 3 (20.0 kV) to align secondary voltages with the nominal 400/230 V standard, thereby decreasing conductor current and mitigating energy losses. In addition, a grounding system installation was implemented to enhance system stability and reduce voltage fluctuations. Following these improvements, the end-voltage on the Low Voltage Network (LVN) increased from 202 V to 217 V, resulting in an energy-loss reduction of 2.973 kW, equivalent to IDR 2,990,505 in cost savings. The results confirm that transformer tap adjustment combined with proper grounding implementation provides a practical and effective method for improving voltage regulation and overall distribution system performance.