The goalkeeper, who has spent four years at Bramall Lane, told friends he does not expect to be offered a new deal following last weekend’s game against Scunthorpe.
Howard’s departure means United could be forced to identify a replacement in the transfer market although Aaron Ramsdale, who deputised for George Long during the closing stages of the 2015/16 campaign, is known to have impressed coaching staff with his performances behind the scenes.
Howard’s position will be clarified during a meeting with Nigel Adkins later this week. Despite the continued uncertainty surrounding his own future, the United manager has begun holding individual meetings with every member of the League One club’s squad as he investigates the reasons behind its poor performances last term.
“It’s something we have always done everywhere we have been,” Adkins said. “And is has always served us well, it’s a worthwhile process.”
United finished eleventh in the table - their lowest league position for over three decades - after being beaten by Graham Alexander’s side and Adkins added: “It’s a chance to discuss everything. Measure individual progress and talk things through.
“A lot of good has come from doing this in the past, it’s informative, and it will be again.”
Howard, aged 29, has played under five different managers since joining United on a free transfer from Blackpool in February 2012. A former Arsenal trainee, he has made 104 first team appearances and helped United reach the semi-finals of both the FA Cup and the Capital One Cup before being replaced by Long in their starting eleven. Howard also represented Falkirk, St Mirren, Aberdeen and Cardiff City before arriving in South Yorkshire.
Ramsdale, a member of United’s Steelphalt Youth Academy, was recognised by England at under-18 level earlier this year.