Palmer spent the second half of the season on loan at Pride Park, as Derby fell short of promotion to the Premier League.
The Rams lost to play-off champions Fulham.
The 21-year-old is not a stranger to promotion success, as he helped Huddersfield in their promotion to the Premier League during the 2016/17 season.
He agreed a second season-long deal at Kirklees Stadium, but returned to his parent club after picking up a recurring hamstring injury.
According to 'Sky Sports', Palmer is one of a number of players who are waiting to hear from Chelsea.
He will soon find out whether he will stay with the Blues, go out on loan, or leave the club on a permanent basis.