Wales' commercial property sector is confronting a regulatory shift that landlords and investors across the UK would be wise to treat as an early warning rather than a devolved curiosity. New scrutiny of Energy Performance Certificate (EPC) compliance in the Welsh market signals the sharpening enforcement of Minimum Energy Efficiency Standards (MEES) that has been building since 2018, and it lands at a moment when the trajectory of UK policy is unmistakable: commercial landlords face a march towards EPC B ratings by 2030, with an EPC C threshold widely expected to become mandatory as early as 2027 under proposals the previous and current governments have both signalled support for.