Interest rate swap

United States Internal Revenue Service

Irwin R. Schyster, professional wrestler

Indian Remote Sensing satellite

Indian Revenue Service (IRS)

I.R.S. Records

IRS is an abbreviation of Insanity Reigns Supreme, a Belgian metal band.

Inertial Reference System; see Inertial guidance system

Intelligent Register System

Independent rear suspension, used in automobiles.

Institute of Regional Studies

Intergroup Rhabdomyosarcoma Study Group, about the cancer, rhabdomyosarcoma

Integrated reception system for TV and radio signals

International Register of Shipping

Industrial Railway Society, a UK railway society

Insulin receptor substrate, protein family involved in the insulin signaling pathway (insulin response)

International Retail Service - A service provided by the LSE that allows UK investors to trade in international stocks in Pound sterling.

IRS (group), is a Canadian rap group

"IRS" is a song by the band Guns N' Roses that is going to be included on the forthcoming Chinese Democracy LP

IRSA Inversiones Representaciones S.A., a real estate company in Argentina represented by an American Depositary Receipt on the New York Stock Exchange