Armored Core: Nexus, a game published by From Software for the PlayStation 2

African Cup of Nations, an international football competition for Confederation of African Football nations

Accenture (NYSE: ACN)

Achang (ISO/DIS 639-3 code: ACN)

Anglican Communion Network, a missionary organisation based in North America

ACN is a three-letter acronym that may refer to:

American Collectibles Network, the former name of an American television network now known as Jewelry Television

Architecture for Control Networks, a network protocol for theatrical control

Australian Company Number, a number issued by the Australian Securities and Investments Commission to registered companies

Acrylonitrile, a precursor monomer in the manufacture of synthetic polymers

Ante Christum Natum, the Latin equivalent of B.C., seldom used in English

Achnasheen railway station (National Rail code: ACN), a United Kingdom railway station

ACN Inc., a multi-level marketing company selling telecommunications services

Andean Community of Nations, a trade block in South America