3L

3L or 3-L may refer to:


 * 3L, or Economic Synergy, a political group in Hong Kong
 * Third (final) year law school student in the United States
 * 3L, IATA code of Air Arabia Abu Dhabi
 * 3L, then IATA code of InterSky which operated until 2015
 * Federal Election Commission (FEC) Form 3L, or Report of Contributions Bundled by Lobbyists, in which federal campaigns and committees must disclose certain contributions received to the FEC at regular intervals
 * 3L, a model of the 4-cylinder diesel Toyota L engine
 * Ford 3L GT or F3L, a sports prototype racing car model introduced in March 1968
 * Bentley 3L or Bentley 3 Litre, a 1920s sports car
 * SSH 3L or Secondary State Highway 3L, a road which became Washington State Route 126
 * Lupo 3L, a model of the Volkswagen Lupo automobile
 * SEAT Arosa 3L, a model of the SEAT Arosa automobile
 * Curtiss HS-3L, a single-engined patrol flying boat built for the United States Navy during World War I