SWL may refer to:
- Shortwave listening, the hobby of listening to shortwave radio broadcasts
- Sound power level, a measure of sound power
- Socialist Workers League, a political organization of Israeli Trotskyists
- Stillwater - Westport Line, a part of New Zealand's national rail network
- Swale railway station, in Kent, England
- Shiny White Lights, a ska band from Gaithersburg, Maryland
- State-Wide League, an alternate name for the Tasmanian Football League
- Safe Working Load, a rating for how much weight a crane or similar lifting device can support
- Scheme Widget Library, a windowing and graphics package for Chez Scheme