The report is high regarded in UK business for highlighting the integration of corporate strategy into business practice.
Ann Loughrey, head of corporate social responsibility at ScottishPower, said retaining the status was "a remarkable achievement".
"We remain committed to being a socially responsible company with best practice in corporate governance, business topics and respect for the environment," he added.
"This commitment creates a sense of belonging and trust amongst stakeholders and it is encouraging to receive external recognition of our work in this area."
ScottishPower recently announced it has installed the first wind turbines at its new renewable energy project in Perthshire.
The provider's site will feature 18 turbines when it is completed and provide energy for over 15,000 homes.
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