Truce of Deulino (also known as Peace or Treaty of Dywilino) was signed on 11 December 1618 and took effect on 4 January 1619. It concluded the Polish–Muscovite War (1605–1618) between the Polish–Lithuanian Commonwealth and the Tsardom of Russia.
The agreement marked the greatest geographical expansion of the Commonwealth, which lasted until the Commonwealth conceded the loss of Livonia in 1629. The Commonwealth gained control over the Smolensk and Chernihiv Voivodeships. The truce was set to expire in 14.5 years. The parties exchanged prisoners, including Filaret Romanov, Patriarch of Moscow.
Władysław IV, son of Commonwealth king Sigismund III Vasa, refused to relinquish his claim to the Moscow throne. Therefore in 1632, when the Truce of Deulino expired and Sigismund III died, and hostilities were immediately resumed in the course of a conflict known as the Smolensk War, which ended in the Treaty of Polanów in 1635.