Season ticket holders are advised that their seats for the pre-season friendlies at the Proact will be held until the middle of next week.
Season ticket holders have until 5pm on Wednesday, July 8 to claim their seats for the games against Hull City and Burnley.
Hull visit the Proact on Tuesday, July 21 (7.30pm) while former Spireite Sean Dyche brings his Burnley side to north Derbyshire on Saturday, July 25 (3pm).
Tickets - priced at £12 for adults and £6 for concessions - can be purchased online or from the ticket office at the stadium.
Chesterfield's pre-season programme gets underway with a game at Matlock Town next Thursday (7.45pm) and they are also in action at Buxton the following night.
Admission to the Matlock match will cost £9 for adults, £5.50 for concessions and £2 for under-12s.
For the Buxton match, admission will cost £6 for adults and £4 for concessions. Under-14s will gain free admission if accompanying an adult paying full admission.