Isa
- Dora the Explorer (TV series)
- ESA (disambiguation)
- ISA (Days of Our Lives)
- ISA Brown
- Ideological state apparatus
- Income share agreement
- Independent Safeguarding Authority
- Independent Schools Association (Australia)
- Independent Schools Association (UK)
- Indian Squash Academy
- Individual savings account
- Industry Standard Architecture
- Infectious salmon anemia
- Iniciativa de Salud de las Americas
- Innovative Software Applications
- Institute for the Study of the Americas
- Instituto Superior de Agronomia
- Instituto Superior de Arte
- Instruction set architecture
- Intelligence Services Act 1994
- Intelligence Support Activity
- Intelligent speed adaptation
- Interconexion Electrica
- Internal Security Act (disambiguation)
- Internal Security Agency
- International Federation of the National Standardizing Associations
- International School Amsterdam
- International School Augsburg
- International School of Aleppo
- International School of Athens
- International School of the Americas
- International Seabed Authority
- International Searching Authority
- International Seismological Association
- International Socialist Alternative
- International Society of Arboriculture
- International Society of Automation
- International Sociological Association
- International Solar Alliance
- International Soling Association
- International Standard Atmosphere
- International Standards on Auditing
- International Studies Association
- International Surfing Association
- International Symbol of Access
- Internet Security and Acceleration
- Interoperability Solutions for European Public Administrations
- Intrinsic sympatheticomimetic activity
- Invention Secrecy Act
- Iranian Space Agency
- Irish Sailing Association
- Is-a
- Isa (Enslaved album)
- Isa (Zaz album)
- Isa (film)
- Isa (moth)
- Isa (name)
- Isa (river)
- Isa District, Kagoshima
- Isa Khan Munj
- Isa Maud Ilsen
- Isa Tengblad
- Isa Town
- Isa, Amur Oblast
- Isa, Kagoshima
- Isa, Nigeria
- Isabel
- Isadora
- Isaz
- Isha (disambiguation)
- Islamic Saudi Academy
- Isosaccharinic acid
- Israel Securities Authority
- Israel Security Agency
- Israel Space Agency
- Israel State Archives
- Issa (disambiguation)
- Italian Space Agency
- Jesus in Islam
- Juan Isa
- Killzone (series)
- Mount Isa
- Mount Isa Airport
- Punjabi Muslims
- STAYC
- Slackline
- United Kingdom