Aneke left the Addicks last summer to join Championship side Birmingham after a two-year spell at the Valley.
The forward has served mostly as a substitute for Blues this season as he has made eighteen appearances in the league, but only one start.
At St. Andrew’s he worked under his former boss at the Valley, Lee Bowyer, but it has not stopped him struggling for game-time.
As such, the striker is expected to return to the Valley and improve manager Johnnie Jackson’s attacking prospects.
The Addicks are believed to be ready to pay £300,000 to the Blues for the forward, whose contract at St. Andrew’s ran out at the end of next season.
In his two seasons at the Valley, Aneke made more than 60 appearances for the Addicks in all competitions and scored seventeen goals.
If the transfer does indeed go through it will be the Addicks’ first signing of this transfer window and Aneke will be hoping he can regain his form at the Valley.