The Reds made the move before the series finale against the Washington Nationals. Votto already had missed five games with a quadriceps strain in his left knee.
The Reds had kept playing a man short, expecting Votto would return quickly. Manager Bryan Price said Tuesday that he was optimistic Votto would be back for a homestand that starts Friday.
That won't be the case.
"We don't want to give Joey a week off and then have Joey slightly improved from when we left him," Price said after Wednesday's 2-1 win. "We may not be able to get him to 100 percent during the year, but 90 percent would be a lot better than 50 percent."
The move is retroactive to May 16.
Votto is hitting .257 with six home runs and 12 RBIs.
The Reds also reinstated outfielder Jay Bruce from the 15-day DL. He had arthroscopic surgery May 5 to repair a torn meniscus in his left knee. He did not play Wednesday.