The Poland international has long been linked with a move away from the German champions, with Manchester United among the favourites to land him.
Now his representative, Cezary Kucharski, has claimed that the 24-year-old already knows where he is going, hinting that he will leave Dortmund this summer.
"Robert has made his decision. Only he decides when he will make his decision public, though," Kucharski told Polish TV.
"Those who have followed Robert's career will realise that he's never stayed at a club for longer than two seasons.
"He's already in his third season at Dortmund. Read between the lines and you'll know what this means."
Lewandowski's current deal has just over 12 months to run.