SNI may refer to:
Science and technology Substitution nucleophilic internal, a chemistry reaction mechanism Swedish Standard Industrial Classification, a Swedish economic classification system Server Name Indication, an extension to the TLS computer networking protocol
Companies Scripps Networks Interactive, a media company Showtime Networks Inc., an American cable network company Siemens Nixdorf Informationssysteme, a former computer hardware company Société Nationale d'Investissement, a Moroccan conglomerate Sports Network Incorporated, a former American media company
Organizations National Information Service (Brazil), or , the former name of the Brazilian Intelligence Agency Seicho-no-Ie, a Japanese new religion Shelter Now International, a Christian foreign aid organization, based in Germany and historically focused on Pakistan and Afghanistan Sistema Nacional de Investigadores, a Mexican government agency Soviet Naval Infantry Swiss Nanoscience Institute
Other uses Standar Nasional Indonesia (Indonesian National Standard), formulated by the National Standardization Agency