Ust-Mil (; , Mil) is a rural locality (a selo), the only inhabited locality, and the administrative center of Milsky Rural Okrug in Ust-Maysky District of the Sakha Republic, Russia, located from Ust-Maya, the administrative center of the district. Its population as of the 2010 Census was 292, down from 405 recorded during the 2002 Census. On 5 July 2022, a maximum temperature of was registered.