Using a broad institutional theory lens, this paper examines the climate change strategies and carbon accounting practices adopted by two New Zealand electricity firms in response to changes in government climate change policies over time (2002–12). The two firms pursue different strategic responses to climate change‐related institutional and economic pressures in order to maintain both legitimacy and a competitive advantage. Five different strategic responses are identified: avoidance, operational conformance, strategic conformance, strategic differentiation, negotiation and manipulation. Firm‐level characteristics are also important drivers of inter‐firm variations in the strategic responses. Further, carbon accounting makes the greatest contribution to carbon reduction when integrated as part of strategic processes that support strategic conformance and strategic differentiation. Carbon monitoring systems, internal carbon information use and carbon disclosure were the main forms of carbon accounting used to realise the different strategies employed.