Sir Christopher Lowther, 1st Baronet (d April 1644) was an English merchant and landowner, responsible for the initial development of Whitehaven as a port.
He also developed salt works around Whitehaven in conjunction with Sir George Radcliffe, then influential in Irish politics.
After Sir John's death, Christopher inherited the manor of St Bees in Whitehaven, and he and his brothers appear to have separated their mercantile concerns, notwithstanding the family principle of cooperation in business.
He married Frances Lancaster (c. 1624–1647) on 6 September 1638, with whom he had two children: Lowther served as High Sheriff of Cumberland in 1641, and suffered losses that year when the Irish Rebellion of 1641 destroyed his iron furnaces in that country and generally disrupted trade.
A Cavalier, his declining health prevented him from active campaigning, although he was in nominal command of a regiment of foot under William Cavendish (later 1st Duke of Newcastle upon Tyne) and governor of Whitehaven and Cockermouth Castle.