The environmental impacts of large language models (LLMs) often remain invisible in business adoption. This paper presents an awareness framework to support the sustainable selection of LLMs, developed using a design science research approach within the marketing department of a major European engineering and technology company. Addressing the lack of transparency and emissions data from LLM providers, the artefact calculates electricity use, carbon emissions, and material impacts of inference tasks and visualises them in an interactive dashboard. Evaluation workshops with stakeholders from marketing, sustainability, and AI strategy confirmed the framework’s potential to foster awareness, support sustainable decision-making, and align AI use with corporate environmental goals and the UN Sustainable Development Goals (SDG). The framework is transferable to other business contexts.