The Ustya (Russian: Устья) is a river in Kotlassky, Krasnoborsky, Ustyansky, and Velsky Districts of Arkhangelsk Oblast in Russia.

There it turns west and enters Ustyansky District, where the major part of its course is located.

Downstream of Oktyabrsky, the Ustya turns north-west again and enters Velsky District.

There it accepts a major tributary, the Kokshenga, from the left, 20 kilometres (12 mi) from its confluence with the Vaga.

The portion of the river which is 14 kilometres (9 mi) in its lower course from Blagoveshchenskoye downstream is listed in the State Water Register of Russia as navigable.