NACC may refer to:
- National Assessment on Climate Change, a massive multidisciplinary effort to study and portray the potential effects of human-induced global warming on the United States
- National Association for Colitis and Crohn's Disease (UK)
- National Association of Catholic Chaplains, a professional association for certified chaplains and clinical pastoral educators.
- National Association of Counsel for Children, an association that aims to improve legal representation for children.
- National Autocycle and Cyclemotor Club
- National Automobile Chamber of Commerce, an early name for the Automobile Manufacturers Association,
- Naval Acquisition Career Center or Naval Acquisition Intern Program
- North American Choral Company, a choir based out of Grand Rapids, Michigan, USA
- North American Christian Convention, an annual meeting of ministers and other active leaders in the Independent Christian Churches/Churches of Christ
- North American Competitiveness Council, an official tri-national working group of the Security and Prosperity Partnership of North America
- North Atlantic Cooperation Council, the precursor to the Euro-Atlantic Partnership Council
- Northeast Alabama Community College, a two-year community college on the border of Jackson and DeKalb Counties.
- Norwegian American Chamber of Commerce
- North American Car Co., a manufacturer of railroad rolling stock
- Northern Athletics Collegiate Conference A conference competing in NCAA Division III in the Upper Midwest.
- Nucleus accumbens, a brain structure
- National Anti-Corruption Commission in Thailand