IOU (disambiguation)

An IOU is an acknowledgment of debt.

IOU may also refer to:

Music

 * I.O.U. (album), album by British jazz fusion guitarist Allan Holdsworth, 1982
 * I.O.U., album by Gregory Isaacs, 1982
 * "I.O.U." (Freeez song), 1983
 * "I.O.U." (Jimmy Dean song), 1976
 * "I.O.U." (Mike Shinoda song), 2018
 * "I.O.U." (Lee Greenwood song), 1983
 * "IOU", 2022 song by Five Finger Death Punch from AfterLife
 * "I.O.U", 2020 song by NCT from NCT 2020 Resonance Pt. 2
 * I.O.U. (hip hop group)

Organizations

 * Investor-owned utility, a supplier of basic services
 * Intercultural Open University Foundation, a distance education institution
 * Islamic Online University, an online, distance-learning university founded by Bilal Philips
 * International Ornithologists' Union, new name of the International Ornithological Committee

Other uses

 * Interdependent Occupational Unit, the monetary unit of the Kingdom of Lovely in the British television series How to Start Your Own Country
 * GURPS Illuminati University, a sourcebook for the GURPS role-playing game
 * Intersection over union, a measure for the similarity of two sets, which is also known as Jaccard index