The 23-year-old has been released from his contract with the relegated Canaries and Derby chairman of football Adam Pearson believes he will prove to be one of the best Bosman signings of the summer.
"We are getting really close on Lee Croft and should be able to make an announcement on that around the middle of next week," Pearson told the Derby Telegraph. "He is someone we targeted really early because we knew there would be a lot of interest in him, so we put a concrete offer on the table and we are now virtually there on the deal.
"Lee knows all about Derby and the size of the club, which is important to him. He thinks it will be the right environment for him and we think he is the right type of player for us.
"We feel that Lee is one of the best free signings you could make this summer. He is 24 next week, so he is still young, he works hard, he has got good pace and he wants to get back in the Premier League.
"Lee was very successful at Norwich last season, in a struggling team, and we expect him to be a good addition for us."