It is narrated from Hazrat Abu Huraira (may Allah be pleased with him) that the Noble Prophet (peace and blessings be upon him) said: Hospitality is for three days, and whatever (is given) after that is charity.
Hadith Referenceمسند احمد / مسند المكثرين من الصحابة / 9564
Hadith Gradingحکم دارالسلام:حدیث صحیح ، و ھذا إسناد حسن