Measuring the social impact of organizations is complex and challenging, and it cannot be generalized to all cases. This conceptual study aims to theoretically substantiate a flexible measure of societal impact and provide recommendations to improve the accuracy and validity of such measures. The Core Organizational Societal Impact (COSI) measure is based on stakeholder, corporate social responsibility, and societal sustainability theories, assessing any organization’s societal impact, comprising indicators of general application and discretionary ones. This model can be used as a proxy and acid test to measure organizational societal footprint, i.e., how organizations impact the stakeholders based on their economic, social, legal, ethical, ecological, psychological, and discretionary responsibilities. It constitutes an adjustable index that allows for assessing the organization’s evolution and comparisons with other organizations in the activity sector. This approach sensitizes managers and entrepreneurs in any activity sector to choose a marketing strategy with a positive societal impact.