Holtby is a surname. Notable people with the surname include:
Braden Holtby (born 1989), Canadian ice hockey player John Holtby (born 1982), English rugby union player Lewis Holtby (born 1990), German footballer Richard Holtby (1553–1640), English Jesuit Superior and Roman Catholic priest Winifred Holtby (1898–1935), English novelist and journalist