Chesterfield’s 10th signing of the summer is a loanee from Sheffield United.
Louis Reed, who is expected to fly out and join the rest of the squad on their pre-season training camp in Spain, is a midfielder who made his Blades debut in 2014.
The 19-year-old has made 39 League appearances for the Bramall Lane outfit, although his last game in league action came in the 2015/16 season.
Mansfield Town were also said to be monitoring the teenager with a view to taking him on loan.
Reed will join fellow new boys Jordan Sinnott and Jak McCourt in the midfield.
Boss Gary Caldwell is thought to be targeting one more new face ahead of the League Two season.
The Spireites take on Benfica B at Vila Real de Santo Antonio tonight, with a return to the stadium in Portugal on Saturday for the friendly against Middlesbrough.