This study provides a detailed case study assessment of two business sites in the UK, to understand the policy drivers of increases to their energy costs and energy bills, considering all current UK energy and climate change policies. We compare our findings to more generalised, theoretical calculations of the policy cost impact on energy costs and bills - we have found no other studies as comprehensive as ours in terms of policy coverage. We find that for one site the government has over-estimated the likely energy savings due to energy efficiency options. Such differences in estimates should be taken into account when considering the efficacy of climate change policies on future energy savings. The overall impact of energy and climate change policies on costs will be of the order 0.4% of total business costs by 2020. This provides an important metric for the near-term cost of mitigation to meet longer-term climate change goals. (C) 2016 Elsevier Ltd. All rights reserved.