Impa, a recurring character in The Legend of Zelda series
Impa Kasanganay (born 1994), American mixed martial artist
Industrias Metalúrgicas y Plasticas Argentinas S.A., an Argentine aircraft manufacturer which made the IMPA Tu-Sa, a civil aviation trainer aircraft
International Marine Purchasing Association, a marine supply-chain organization; see IMPA coding
Interplanetary Monitoring Platform-A (IMP-A or IMP 1), a research satellite launched in 1963 as part of the Explorer program
International Motor Press Association, a trade association representing automotive journalists and public relations professionals in the United States
Instituto Nacional de Matemática Pura e Aplicada, Brazil's National Institute for Pure and Applied Mathematics
EET Nº7 Taller Regional Quilmes (IMPA), a high school in Quilmes, Buenos Aires
isopropyl methylphosphonic acid, a metabolite of sarin
International Mission Photography Archive (IMPA), a repository in the USC Digital Archive offering historical photographs from the archives of international missionary organizations.
IMPA1 (Inositol(myo)-1(or 4)-monophosphatase 1), a human gene
Impa shilup, or "Nalusa chito", the soul eater, one of the Choctaw mythology Shadow-like beings