The 23-year-old was offered a new contract at the end of last season and Coke's agent has confirmed he wants to sign up.
"I am pleased Giles has decided to stay with us next season," said Northampton manager Stuart Gray.
"He is a player with a huge amount of natural ability and a lot of potential. He was very influential for us the season before last with some important goals from midfield and while last season was obviously disappointing for all of us, I am sure he can be a big player for us this season.
"You need goals from all over the field if you are to be successful and Giles is one who can certainly chip in from midfield. I am pleased he will be with us and looking forward to getting back to work on July 1."