The Usta (Russian: Уста) is a river in Nizhny Novgorod and Kirov Oblasts, Russia. It is a left tributary of the Vetluga. It is 253 kilometers in length, with a drainage basin of 6,030 square kilometers. Most of its water comes from melting snow. The average discharge 47 kilometers from its mouth is 28 cubic meters per second. The Usta freezes over in November, and stays icebound until April. It is navigable in its lower reaches. The town of Uren is located on the right bank of the Usta.
