Abstract To address the instability challenges of Partial Nitrification and Anammox (PNA) at low temperatures, this study introduces a temperature-based nitrogen removal process and demonstrates its feasibility in a pilot-scale system. The temperature-based strategy allows for the selective enhancement of anammox at higher temperatures (>20 °C) or denitrification at moderate and lower temperatures (≤20 °C). Nitrogen removal efficiencies of 93.8%, 72.1%, and 59.1% were achieved under >20 °C, 15–20 °C, and