"Cork, who was on loan at Southampton earlier in the season from Chelsea, told me how good a club Scunthorpe was. He had nothing but good things to say," Mills told the official website.
"Scunthorpe are flying high in the table, also with a couple of games in hand, and hopefully I can help them in their promotion push."
He also hopes that he can play a part at Wembley in the final of the Johnstone's Paint Trophy - something he regards as a "dream".
Mills started his career as a striker but was converted into an attacking left-back and started the season brightly before niggling injuries kept him out of the side.
"I want to get as many games under my belt as I can, play well and hopefully help them become a promotion team and put them back in the Championship - where they belong." he added.