Cigarette filters, a leading source of non-biodegradable plastic waste with over 4.5 trillion discarded annually, have been largely overlooked in global plastic policy discussions despite their significant environmental impact. This research highlights how tobacco control is increasingly framed as an environmental issue, driven by advocacy efforts linking tobacco waste to plastic pollution and environmental justice. It exposes the tobacco industry’s indirect influence on international negotiations—particularly the UN Plastics Treaty—through greenwashing campaigns, front groups, and recycling programs that deflect responsibility. Key barriers include low awareness that filters are plastic, weakening treaty language, geopolitical divides, and lack of transparency. The study recommends banning plastic filters, implementing Extended Producer Responsibility for tobacco companies, and strengthening safeguards against industry interference.