John M'Millan III, the son of John M'Millan II, was born in 1752, and was licensed on January 4, 1775, at Pentland. On March 19, 1777, he received no fewer than four calls—Inverkeithing, Hamilton, Stirling, and Merse and Teviotdale. He took some time to decide. On July 21 he rejected Inverkeithing and Merse and Teviotdale, and on September 1 he accepted Stirling. On March 11, 1778, he was ordained. In 1802, M'Millan was nominated theological tutor, and on August 17, 1803, he accepted office. He died on October 20, 1819, at Edinburgh, on the way home from Bath. The Presbytery spoke of him as "an ornament to his profession, a judicious and able minister," and the Synod in its obituary notice of him as "having laboured with unusual acceptance and ability in the service to the Church."