Laurence Maguire has pledged his future to the club by signing a new two-and-a-half-year contract.
The 21-year-old defender, who is a product of the club's academy, said: "I'm delighted to get the deal over the line as I've been here a long time now and I was keen to stay.
"The club has a big place in my heart and I want to help Chesterfield get back to the EFL."
Chief executive Graham Bean said: "We are very pleased to have secured Laurence on a new deal. This demonstrates the commitment from the club to hold on to young, upcoming players."
Maguire was handed his first professional contract in the summer of 2014 and has scored two goals in 59 appearances for the Spireites.