Just more than six months later, On February 24, 1864, Blunt was appointed Captain and Assistant Quartermaster of Volunteers, and was ordered to report to the Commanding General, Department of Virginia and North Carolina, for duty in the Quartermaster's Department, which duties he assumed on April 25. He became the Depot Quartermaster for the Army of the James on May 4, 1864, and served in this position until late 1865. In recognition of his meritorious service at the Battle at Lee's Mills and Savage's Station, President Andrew Johnson, on May 4, 1866, nominated Blunt for appointment to the grade of brevet brigadier general of volunteers, to rank from March 13, 1865, and the United States Senate confirmed the appointment on May 18, 1866. He also received appointments to the brevet grades of major, lieutenant colonel and colonel of volunteers, Quartermaster's Department, to rank from June 9, 1865. He received appointments to the same brevet grades in the Regular Army to rank from March 2, 1867.