|Headquarters||Chicago, Illinois, U.S.|
IGA is a U.S. brand of grocery stores that operates in more than 30 countries. Unlike the chain store business model, IGA operates as a franchise through stores that are owned separately from the brand. Many of these stores operate in small town markets and belong to families that manage them. It was founded in the United States as the Independent Grocers Alliance. The headquarters is in Chicago, Illinois. IPA is also owned by IGA in Ontario Canada. 
IGA was started in May 1926 when a group of 100 independent retailers in Poughkeepsie, New York, and Sharon, Connecticut, led by J. Frank Grimes, organized themselves into a single marketing system. Guidance from the IGA management came in the form of marketing and access to a consistent supply chain. After a few years, the company began making its own canned food brand.
By the end of its first year the group had expanded to include more than 150 retailers. In 1930 there were over 8,000 grocery stores using the IGA name.
William Olsen was the company CEO until 1988, when he was replaced by Thomas Haggai. Haggai retired in 2016.
The company uses the "Hometown Proud Supermarkets" slogan. Today, many IGA grocery stores are still located in smaller cities and towns throughout the United States.
The stores in the alliance remain independently owned and operated. The alliance oversees several resources shared among the member stores. These include, most visibly, the IGA store brand products and the logistical network that distributes them. The alliance also provides training and assessment programs and an online advertising platform. It regularly coordinates promotional events and charity fundraising events that benefit store communities.
In Canada (apart from British Columbia), IGA is a group of independent grocers supplied by Sobeys, which franchises the name. Acquired by Sobeys as part of its purchase of the Oshawa Group Ltd., it now operates primarily in Quebec. The IGA operations in Atlantic Canada were sold to Loblaw Companies Limited (except for Edmundston, New Brunswick) and were restructured under its existing brands. The company-owned stores west of Quebec now mainly operate under the Sobeys banner. In Ontario, Sobeys forced franchise-owned IGA stores to convert to the Foodland banner, and announced the closure of the IGA program in Ontario. There are, however, many IGA stores still operating in Manitoba, Saskatchewan and Alberta, with one opening in Emerald Park, Saskatchewan in 2016. 
IGA Extra locations are larger and carry a wider variety of general merchandise, more akin to the hypermarket model. They include a pharmacy, large bakery, a bank, a bistro, a post office and a larger selection of food items. IGA Extra launched in the early 2000s to take the place of Sobeys locations in the Quebec City and Montreal areas. In 2015, several COOP Atlantic stores became IGA stores supplied by Sobeys Quebec after COOP decided to exit the grocery store business.
In addition, IGA in Quebec also operates smaller supermarkets, such as Bonichoix and Tradition (a brand introduced in 1999).
In British Columbia, IGA stores (previously Marketplace IGA) are, for the most part, independently owned and are supplied by the H.Y. Louie Co.
The Independent Grocers of Australia brand is owned by Metcash, an Australian retailer and wholesaler. This company supplies groceries, promotional materials and other things to a large number of locally owned Australian supermarkets, and a few smaller chains. Collectively, they are the third biggest competitor in major Australian supermarkets, after Coles and Woolworths.
In Western Australia On May 1, 2006, IGA grew to include Dewsons, Action, Advantage, Four Square and SupaValu after Western Australia's largest independent retailer Foodland Associated Limited had sold all of its supermarkets and distribution networks to Metcash IGA Distribution Pty Ltd and Woolworths Limited. Subsequent rebranding by Metcash and Woolworths has eliminated any previous links with Western Australian retail heritage.
Walter Mart Supermarket is the first and only alliance member in the Philippines with 21 locations, mostly in Metro Manila and Luzon - from Gapan, Nueva Ecija in the north to Tanauan, Batangas in the south.
IGA Foodliner in Bowman, South Carolina.
New IGA storefront in Springboro, Ohio.
Pat's Foods IGA in Calumet, Michigan.
- List of supermarket chains
- "Contact IGA." IGA. Retrieved on February 27, 2010.
-  Ernie Smith, The Surprisingly Resilient History of IGA, Which Gave Small Towns Groceries (atlas obscura, 11 July 2016)
- IGA (Canada) - Fresh Food, Friendly Neighbours
- Regina Leader-Post (26 August 2016). "First IGA store in Western Canada in 15 years opens in Emerald Park". Retrieved 10 October 2016.
- H.Y. Louie Co. Limited to join IGA International Archived 2006-03-27 at the Wayback Machine., IGA Press Release, February 10, 2005.
- Walter Mart website