An English country house is a large house or mansion in the English countryside. Such houses were often owned by individuals who also owned a town house. This allowed them to spend time in the country and in the city—hence, for these people, the term distinguished between town and country.

However, many were, and often still are, the full-time residence for the landed gentry who dominated rural England until the Reform Act 1832. Frequently, the formal business of the counties was transacted in these country houses, having functional antecedents in manor houses.

With large numbers of indoor and outdoor staff, country houses were important as places of employment for many rural communities. In turn, until the agricultural depressions of the 1870s, the estates, of which country houses were the hub, provided their owners with incomes. The late 19th and early 20th centuries were the swansong of the traditional English country house lifestyle. Increased taxation and the effects of World War I led to the demolition of hundreds of houses; those that remained had to adapt to survive.

While a château or a Schloss can be fortified or unfortified, a country house, similar to an Ansitz, is usually unfortified. Some English country houses were given castellated designs, but many buildings with "castle" in their name—such as Highclere Castle—were never fortified; in such cases, the title reflects architectural fashion rather than defence.

The term stately home is subject to debate, and avoided by historians and other academics. As a description of a country house, the term was first used in a poem by Felicia Hemans, "The Homes of England", originally published in Blackwood's Magazine in 1827. In the 20th century, the term was later popularised in a song by Noël Coward.

In England, the terms "country house" and "stately home" are sometimes used vaguely and interchangeably; however, many country houses such as Ascott in Buckinghamshire were deliberately designed not to be stately, and to harmonise with the landscape, while some of the great houses such as Kedleston Hall and Holkham Hall were built as "power houses" to dominate the landscape, and were most certainly intended to be "stately" and impressive.

In his book Historic Houses: Conversations in Stately Homes, the author and journalist Robert Harling documents nineteen "stately homes"; these range in size from the vast Blenheim Palace and Castle Howard to the minuscule Ebberston Hall, and in architecture from the Jacobean Renaissance of Hatfield House to the eccentricities of Sezincote.

The book's collection of stately homes also includes George IV's Brighton town palace, the Royal Pavilion.