Charles Calvert, 3rd Baron Baltimore, English politician, 2nd Proprietor of Maryland (died 1715)

Charles Calvert, 3rd Baron Baltimore was an English colonial administrator. He inherited the province of Maryland in 1675 upon the death of his father, Cecil Calvert, 2nd Baron Baltimore. He had been his father's Deputy Governor since 1661 when he arrived in the colony at the age of 24. However, Charles left Maryland for England in 1684 and would never return. The events following the Glorious Revolution in England in 1688 would cost Calvert his title to Maryland; in 1689 the royal charter to the colony was withdrawn, leading to direct rule by the British Crown. Calvert's political problems were largely caused by his Roman Catholic faith which was at odds with the established Church of England.

The Province of Maryland was a proprietary colony, in the hands of the Calvert family, who held it from 1633 to 1689, and again from 1715 to 1776. George Calvert, 1st Baron Baltimore (1580–1632) is often regarded as the founder of Maryland, but he died before the colony could be organized.