Haile Gold Mine is an open pit gold mine located in the state of South Carolina, USA. The concentrator consists of a semi-autogenous mill–ball mill–pebble crusher (SABC) circuit, flash flotation, rougher flotation, concentrate regrind mills, leaching electrowinning and refinery. This paper focuses on the regrinding section. The original regrind circuit consists of six units of stirred media detritor that receives a combined flash and rougher flotation concentrates feed. The circuit could not cope with the coarser pyrite from the flash flotation concentrate stream that has resulted in a lower mass pull from the flash flotation and coarser product size distribution compared to the design. In 2019, Haile Gold Mine modified the circuit by introducing two stages of regrinding. One unit of ETM 1500 (1300 kW) TowerMill and an M10000 (3000 kW) IsaMill were installed for regrinding duties. This paper focuses on the TowerMill circuit. The TowerMill circuit was designed to reduce the particle size from 150 μm to 22–42 μm. The mill was successfully installed in five days and commissioned within six days in November 2018 and January 2019. For the first three months, the TowerMill was operated in open circuit configuration. In April 2019, the TowerMill circuit was closed with a cluster of 10” hydrocyclones. The leach circuit’s feed was reduced from 23 μm to 17 μm when the TowerMill was brought online. A recent TowerMill circuit performance review indicated that the circuit performs within the design specifications to produce a circuit product of 22 μm at a specific energy consumption of 16.4 kWh/t. The first set of the tip and flight liners’ wear rate was 0.1 and 0.05 g/kWh, respectively. This paper discusses the installation, commissioning and operational experience of the TowerMill circuit plus its process performances.