The duo’s contract were set to expire at the end of the season, but they will now remain with the club until the end of next season.
“This is really good news for us, the pair have become stalwarts at Bramall Lane and will continue to play major roles in the development of the team,” Sheffield United boss Kevin Blackwell told the club’s official website.
“I am delighted and it has come at a good time with me starting to find my best form,” said Quinn.
“It is nice to know where you stand and it is better to be at a club than worrying about the future.
“It seems strange to see all the comings and goings, but I absolutely love it here. To be honest, I couldn’t picture myself anywhere else, but things can change rapidly in football.”
