Acta
- ACTA1
- ACTA2
- Acta (software)
- Actin assembly-inducing protein
- Activin A
- Acts of the Apostles (genre)
- Administrative Council for Terminal Attachments
- Alameda Corridor Transportation Authority
- American Council of Trustees and Alumni
- Anti-Counterfeiting Trade Agreement
- Atlantic County Transportation Authority
- Australian Community Television Alliance
- Canon (canon law)
- Manny Acta