The Championship trio have had bids accepted for the 25-year-old and now face a battle to secure his signature.
Hobbs was recently recalled from a loan spell at Forest but now looks set to leave the KC Stadium permanently.
Hull boss Steve Bruce said: "I would expect Jack to go.
"We have accepted a bid from Forest, we have accepted a bid from Wigan and we have accepted a bid from Reading, so I would expect him by Friday to take up one of those options."
Bruce was, however, unaware of rumoured late interest from Championship leaders Leicester.
"That's news to me, I don't know where that's come from," he added. "Certainly in the last 12 hours the club haven't heard anything that I'm aware of."