ACIA may refer to:
- Arctic Climate Impact Assessment, a study
- Asynchronous Communications Interface Adapter, integrated circuits like MOS6551 and MC6850
- American Committee for Armenian Independence, an early 20th-century support organization
- ASEAN Comprehensive Investment Agreement, an agreement signed by ten ASEAN countries on February 26, 2009 to further liberalize investment regimes with the end goal of the AEC.
Not to be confused with:
- Açaí Palm, of which the Açaí Berry is its fruit.