UIL

UIL may mean:


 * UIL Holdings Corporation, a natural gas company based in Connecticut, U.S.
 * UNESCO Institute for Lifelong Learning, a United Nations educational centre
 * Unione Italiana del Lavoro, the Italian Labour Union
 * United International Airlines, ICAO designator of a Serbian cargo airline
 * United Irish League, a nationalist political party in Ireland from 1898 through the 1920s
 * University Interscholastic League, the governing body for public school interscholastic activities in the US state of Texas
 * User-in-the-loop, a system theoretic paradigm to change user behavior
 * User Interface Language, an X11 application language used by Motif
 * Uil River, a river of Kazakhstan