The 35-year-old has struggled with a knee injury recently and has only made two appearances since November.
However, he is close to returning to fitness and, after fellow centre-backs Jonny Evans and Phil Jones both picked up injuries during Saturday's 2-1 defeat at Stoke City, he could feature regularly in the coming weeks.
"Rio is back training. He's back and we will continue to use Rio at the right times and the right moments," Moyes told reporters.
"Rio has made a great contribution, especially in the first half of the season. I played him in nearly all the opening eight to 10 games. He was a big part in helping me to settle.
"He has competition at centre-half, but he is very much valued and looked at as one of the senior players."
Ferdinand's current United contract is due to expire in June.