SCA may refer to:

Biology and health

• Sickle cell disease, also known as sickle cell anaemia
• Spinocerebellar ataxia, a neurological condition
• Statistical coupling analysis, a method to identify covarying pairs of amino acids in protein multiple sequence alignments
• Sudden cardiac arrest, a condition in which the heart suddenly stops beating, leading to sudden cardiac death
• Superior cerebellar artery, a major blood supplier to the cerebellum

Commercial entities

• Sebastian Conran Associates, a British product and brand development consultancy
• Sony Corporation of America, holding company for Sony's American companies
• Southern Cross Austereo, an Australian media company
• Supercheap Auto, an Australian automotive parts and accessories retailer
• SCA (company) (Svenska Cellulosa Aktiebolaget), a Swedish hygiene products and paper manufacturer

Computing

• SCA (computer virus), an Amiga virus referencing the Swiss Cracking Association
• Service Component Architecture
• Side-channel attack, in cryptography
• Single Connector Attachment or Single Connection Attach, an 80-pin SCSI storage interface
• Software Communications Architecture, in Software-Defined Radio (SDR)
• Static code analysis
• Strong customer authentication
• Software Composition Analysis

Locations

• Seoul Capital Area, Korea
• Singapore Changi Airport
• South and Central America, a country grouping
• Southern Control Area, a Canadian airspace designation
• Soviet Central Asia
• Space Centre Australia

Organizations

• Bureau of South and Central Asian Affairs, in the U.S. Department of State
• Sabah Chinese Association
• Sarawak Chinese Association
• Schuylkill Canal Association, an organization that maintains a section of historical canal in Pennsylvania
• Scottish Canoe Association, the national governing body for paddlesports in Scotland
• Screen Composers of America, an organization co-founded by Jeff Alexander
• Secular Coalition for America
• Sexual Compulsives Anonymous
• Société en commandite par actions, a type of corporation in France
• Society for Creative Anachronism, an international living history group
  • SCA armoured combat, a combat sport developed by the above organization
• Society for Cultural Anthropology, a professional association for cultural anthropologists
• Student Catholic Action, a religious student organization in the Philippines
• Student Conservation Association, a non-profit conservation service organization in the United States
• Suez Canal Authority, a state-owned authority which owns and maintains the Suez Canal
• Supreme Council of Antiquities, the Egyptian antiquities service
• Supreme Court of Albania, the court of last resort in the Republic of Albania
• Swedish Committee for Afghanistan
• Swiss Cricket Association
• Sydney Catchment Authority
• Sydney College of the Arts

Other

• McNamara–O'Hara Service Contract Act
• Senate Constitutional Amendment, the formal name for a type of California ballot proposition
• Shuttle Carrier Aircraft, two Boeing 747 aircraft modified to transport the Space Shuttle
• Small craft advisory
• Solar collector array, a type of solar thermal collector
• Spectrum continuation analysis
• Stored Communications Act, Title II of the US Electronic Communications Privacy Act of 1986
• Subsidiary communications authority, the Federal Communications Commission's name for subcarrier channels transmitted on a broadcast FM station
• Sustainable competitive advantage, a business advantage that is preserved over long term
• USC School of Cinematic Arts, University of Southern California, United States