SxS (S-by-S) is a flash memory standard.

SXS or SxS may also refer to:

• Side-by-side, a configuration of Double-barreled shotgun

• Side by Side (UTV), a class of all-terrain vehicle

• Side-by-side assembly, a Microsoft Windows software technology

• Step-by-step switch, a telephone switching system

• SunExpress, ICAO code for a Turkish-German airline

• SXS Patna, a private Catholic high school in Patna, India