Francis 21, signed for the Blades in March 2004 from Bradford City for £200,000 along with Andy Gray, and made his debut on 27 March in a 2-1 defeat to Cardiff City.
Up until now Francis has played just 8 games (+ 7 as a sub) whilst failing to score, he was last season sent out to Grimsby Town and Tranmere Rovers before Neil Warnock, along with Alan Wright placed him on the transfer list.
Barnsley, who won promotion to the Championship after beating Swansea City 4-3 on penalties in the League One Play-Off Final are looking to bolster their squad and could do by netting Francis for £250,000.