William Baillie, Lord Provand

William Baillie, Lord Provand (died 26 May 1593), was a Scottish judge.
Baillie was of the family of Baillie of Lamington, first appears as a judge of the court of session, 15 November 1550. He was appointed president of the court on the death of John Sinclair, Bishop of Brechin, in 1566. On 6 December 1567, he was deprived of this office, in favour of Sir James Balfour, by the regent Murray, on the pretext that the act of institution required it to be held by a person of the spiritual estate. Balfour was in turn removed in 1568, when he was accused of participation in Darnley's murder, and Baillie, being reinstated, held the office till his death, 26 May 1593.