The T. Eaton Company Limited, later known as Eaton's and then Eaton, was a Canadian department store chain that was once the largest in the country. It was founded in 1869 in Toronto by Timothy Eaton, an immigrant from what is now Northern Ireland. Eaton's grew to become a retail and social institution in Canada, with stores across the country, buying-offices around the globe, and a mail-order catalog that was found in the homes of most Canadians. A changing economic and retail environment in the late twentieth century, along with mismanagement, culminated in the chain's bankruptcy in 1999.

A department store is a retail establishment offering a wide range of consumer goods in different areas of the store, each area ("department") specializing in a product category. In modern major cities, the department store made a dramatic appearance in the middle of the 19th century, and permanently reshaped shopping habits, and the definition of service and luxury. Similar developments were under way in London, in Paris and in New York City (Stewart's).