With Ben Gibson set to return to Tranmere for another stint after injury, Reach looks set to follow him out of the Riverside, while Luke Williams could also be allowed to leave.
Left winger Reach has played 12 first-team games for Boro and has scored three goals.
"Several clubs have asked about Adam," said Mowbray.
"I think, as we move on, if they are not playing, how do you develop players?You either put them in your team and let them learn their lessons as they go along or let them go and play somewhere else.
"Development is about playing Saturday-Tuesday, Saturday-Tuesday. At this moment in time, if the right phonecall comes along we will consider it."
Mowbray admitted Williams could also leave, and said: "We are in no rush. And that works both ways. Those lads have to have a desire to play football and to want to play football.
"They [Reach and Williams] are both still very young boys and it's something we've been discussing with them and their advisors as we move forward."