Brayford, 27 is welcoming signing for the Blades who played 20 times for the Blades (and scored 2 goals) last season whilst on loan from the Bluebirds. He has signed for an undisclosed fee (believed to be over £1 million) and has signed a three and a half year deal - he is however cup-tied in both domestic competitions.
The Blades board have patiently been monitoring his situation who has been a regular in the Cardiff side.
"We are absolutely thrilled he is coming back permanently, John has been at the top of our list for a long time and our patience has finally been rewarded," confirmed boss Nigel Clough. "There aren't very many loan players who galvanise a team and Club like John did last season, simply by his actions on the field. John has made no secret of his desire to return to Sheffield United and as a Club we have finally worn Cardiff City down and they accepted a bid. Russell Slade didn't want to lose John, he has been impressed with him since taking over at Cardiff, but he knew the situation and our admiration wasn't going to go away."
Speaking to sufc.co.uk Clough specifically spoke about the Brayford; "We think it is money well spent. We lost a important defender in Harry Maguire and now in John we feel we have gone a long way to replacing him, he might be a full-back but we think he will be worth every penny. If you had asked our supporters which one realistic player they would want us to sign I am sure they would have all said John and his signing gives us other options within the squad too."
He is likely to make his debut next Saturday at home to Swindon Town.