Although large-scale mercantile houses came to have baths at the end of the Edo period, the full-fledged popularization of home baths was seen later, during the period of rapid growth following World War II.
江戸末期には大店の商家でも内風呂を持つようになったものの、本格的な内風呂の普及は第二次世界大戦以降の高度成長期に下る。