With global warming intensifying, GI endoscopy is among the top three greenhouse gas-emitting medical procedures. Colonoscopy, a cornerstone for colorectal cancer (CRC) screening, significantly contributes to the carbon footprint (CF). This study quantifies CO₂ emissions in different steps of colonoscopy and evaluates the environmental impact of common polypectomy techniques to establish baseline CF data and identify opportunities for mitigation. This study included patients undergoing colonoscopy for CRC screening. CO₂ emissions were comprehensively measured at each step of the procedure (pre-, during, and post-colonoscopy), including energy consumption, all equipment and medications, waste management, and endoscopy reprocessing. Emission data were also collected for common polypectomy techniques, including cold forceps biopsy (CFB), cold snare polypectomy (CSP), hot snare polypectomy (HSP), and hot snare endoscopic mucosal resection (EMR), all performed according to standard polypectomy protocols.