Walter Newall (3 April 1780 – 25 December 1863) was a Scottish architect and civil engineer, born at Doubledyke in the parish of New Abbey, near Dumfries in south-west Scotland. He was the leading architect in the Dumfries area, from the 1820s until his retirement.
Newall began his design career in partnership with an upholsterer and a cabinet maker in the Dumfries firm of Newall, Hannah and Reid. Nothing is known of any architectural training, although Howard Colvin suggests that his knowledge of up-to-date styles points to time spent with an architect of standing.
Throughout his working life he lived mainly in Dumfries, travelling around Dumfriesshire, Kirkcudbrightshire and Wigtownshire in the course of his work. His papers show him to have made tours of Germany and Italy, as well as parts of England, notably Oxford, Cambridge and Fonthill. The architects John Edgar Gregan (1813–55), William Reid Corson (1821–86), his brother George Corson (1829–1910) and James Barbour (1834–1912) all served as apprentices under Newall.
Newall died at Craigend, New Abbey, on Christmas Day, 1863.