AllianceBernstein National Municipal Income Fund is a diversified, closed-end management investment company. The Fund seeks to provide high current income exempt from regular federal income tax by investing substantially all of its net assets in municipal securities that pay interest that is exempt from federal income tax. The Fund will normally invest approximately 80%, and normally substantially all, of its net assets in municipal securities paying interest that is exempt from regular federal income tax. The Fund also normally will invest over 75% of its assets in investment-grade municipal securities or unrated municipal securities. The Fund may invest up to 25% of its net assets in municipal bonds rated below investment-grade and unrated municipal bonds. It invests in various sectors, such as toll roads/transit, healthcare, airport, water and sewer, higher education, electric utility, port and prepay energy. AllianceBernstein L.P. serves as the investment advisor of the Fund.