The parties have agreed on a three-year contract. Barca will submit an offer of around €30-40m when Bayern Munich are ready to negotiate.
As per prior reports, Lewandowski will be pushing for a departure this summer. He has a contract with the Bavarians until 2023 and does not want to extend it.
The 33-year-old has scored 49 goals in 45 games for Bayern this season so far.