The striker joined the League One side from Charlton Athletic during the summer and has since gone on to score four goals in his 22 appearances.
However, manager Shaun Derry has revealed that the 26-year-old can leave Meadow Lane, providing that the club receive an acceptable offer.
"Danny needs to resurrect his career and both parties have agreed that this will be best at another club," Derry told the club's official website. "I'm fully aware of what he possesses as a striker but sadly it's not working out for him here at Notts County.
"The door is never closed for Danny and he'll be constantly involved with the first team on a day-to-day basis. However, if another club is interested in taking him, we are willing to listen to offers."
Haynes started his career with Ipswich Town, before having spells with Bristol City, Barnsley and Charlton.