Sir Samuel Leonard Tilley (born May 8, 1818, Gagetown, N.B.—died June 25, 1896, Saint John, N.B., Can.) was a Canadian politician, an early advocate of the confederation of British North America. He introduced the National Policy, a program of trade protection that became the basis of Canadian fiscal policy.
Tilley acquired considerable wealth in the pharmaceutical business and entered politics in 1850 as a member of the New Brunswick legislature, becoming provincial secretary in 1854 and premier in 1861. He represented New Brunswick in the confederation conferences of 1864, and his defeat in an 1865 general election over the confederation question delayed the progress of negotiations.
Returning to power in 1866, Tilley attended the London conference that passed the British North America Act (1867), creating the Dominion of Canada. He was first minister of customs and excise for the dominion, and he served as minister of customs in Sir John Macdonald’s administration in 1873. After five years as lieutenant governor of New Brunswick (1873–78) Tilley was elected to the Dominion Parliament for Saint John and was again minister of finance in Macdonald’s government, in which office he introduced and applied the National Policy. He was knighted in 1879. In 1885–93 he was once again lieutenant governor of New Brunswick.