In January 2023, Bath and North East Somerset Council (B&NES) introduced the UK’s first planning policies requiring all new buildings to have net zero operational emissions, and limiting construction emissions for larger developments. Coinciding with this, a collaboration was formed between Bath university academics, planning and climate officers at B&NES, and other local organisations, which studied the impacts of, and reception to, these pioneering policies over a six-month period. This project evaluates the success of the policies two years on, establishing long-term trends, opportunities for refinement, and the national policy implications of this unique policy case study.