The striker joined the 'Blades' immediately after ending his stint at Loftus Road by mutual consent.
Washington spent two and half season with the London club, in which time he made 92 appearances in all competitions and scored 14 goals.
However, he is yet to make an appearance this season despite the Championship being five games in to the new campaign.
He will now move up to Yorkshire to play for Sheffield United on a year-long deal, who are in 7th place in the second division of English football, compared to QPR who are in 22nd position.
August 31, 2018