HSA may refer to:
- Haiku Society of America
- The Harlem School of the Arts
- Hawker Siddelely Aviation
- Health savings account
- Health Sciences Authority, a statutory board of the Ministry of Health of Singapore
- Heat stable antigen, a cluster of differentiation, also known as CD24
- High School Assessments a Maryland Public School standardized test.
- Hispanic Student Association
- Home School Association, a common name for independent parent groups not associated with a formal Parent-Teacher Association
- Homeland Security Act
- Horizon Science Academy, a Columbus, OH based school.
- Hoffman Sports Association, an organizing body for Freestyle BMX events worldwide
- High Speed Alliance, see HSL-Zuid
- Hmar Students Association
- Human Security Act
- Human serum albumin
- Humane Slaughter Act
- Hunt Saboteurs Association
See also
- The Book of Hosea has a common abbreviation of Hsa.
- East African Safari Air has a ICAO Code of HSA
- Stennis International Airport in Bay St. Louis, Mississippi has a FFA airport code of HSA (the ICAO code is KHSA)
- Hasimara railway station has a code of HSA
- Homeland Security Advisory System
- High Speed Amphibian vehicles from Gibbs, the maker of the Gibbs Aquada, Humdinga and Quadski
